https://docs.opendap.org/index.php?action=history&feed=atom&title=Writing_A_ServerWriting A Server - Revision history2026-04-16T17:54:28ZRevision history for this page on the wikiMediaWiki 1.38.4https://docs.opendap.org/index.php?title=Writing_A_Server&diff=8155&oldid=prevJimg: moved Wiki Testing/WritingAServer to Writing A Server: not part of the testing pages anymore2012-05-07T01:09:47Z<p>moved <a href="/index.php/Wiki_Testing/WritingAServer" class="mw-redirect" title="Wiki Testing/WritingAServer">Wiki Testing/WritingAServer</a> to <a href="/index.php/Writing_A_Server" title="Writing A Server">Writing A Server</a>: not part of the testing pages anymore</p>
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</td></tr></table>Jimghttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1927&oldid=prevYuan: /* FootNotes */2008-01-26T15:31:41Z<p><span dir="auto"><span class="autocomment">FootNotes</span></span></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#For complex data sets, it's likely that you'll need to create some new fields in the data type classes you specialized.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#For complex data sets, it's likely that you'll need to create some new fields in the data type classes you specialized.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#If you're writing a server that will principally be for internal use, or you expect many many small accesses, you should look into using the Java software or implementing your server as an Apache module. Contact support or the dods-tech email list for help with the latter.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#If you're writing a server that will principally be for internal use, or you expect many many small accesses, you should look into using the Java software or implementing your server as an Apache module. Contact support or the dods-tech email list for help with the latter.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>#You can get help from the <del style="font-weight: bold; text-decoration: none;">\xlink{DODS web site}{</del>http://<del style="font-weight: bold; text-decoration: none;">unidata</del>.<del style="font-weight: bold; text-decoration: none;">ucar</del>.<del style="font-weight: bold; text-decoration: none;">edu</del>/<del style="font-weight: bold; text-decoration: none;">packages/dods/}, </del>the <del style="font-weight: bold; text-decoration: none;">\xlink{dods-tech email list}{</del>http://<del style="font-weight: bold; text-decoration: none;">www.unidata.ucar</del>.<del style="font-weight: bold; text-decoration: none;">edu</del>/<del style="font-weight: bold; text-decoration: none;">packages</del>/<del style="font-weight: bold; text-decoration: none;">dods/home/mailLists/subscribe-dods-tech</del>.html<del style="font-weight: bold; text-decoration: none;">} and the \xlink{DODS user support desk}{mailto:support@unidata.ucar.edu}</del>.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>#You can get help from the <ins style="font-weight: bold; text-decoration: none;">[</ins>http://<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org<cite>OPeNDAP Home</cite>], the [mailto:support@opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org<cite>support<</ins>/<ins style="font-weight: bold; text-decoration: none;">cite>] or </ins>the <ins style="font-weight: bold; text-decoration: none;">[</ins>http://<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org</ins>/<ins style="font-weight: bold; text-decoration: none;">support</ins>/<ins style="font-weight: bold; text-decoration: none;">index</ins>.html<ins style="font-weight: bold; text-decoration: none;"><cite>OPeNDAP-TECH</cite>]</ins>.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>#The DODS Project has developed two tools to help with serving datasets that contain many files. The first is to set up a `file server' a kind of catalog of URLs that is itself a DODS data set. The second is called the Aggregation Server (AS). The AS can automatically aggregate discrete datasets, accessed as either as files (in some cases) or URLs to produce a single data set. See the <del style="font-weight: bold; text-decoration: none;">\xlink{DODS web page}{</del>http://<del style="font-weight: bold; text-decoration: none;">unidata.ucar</del>.<del style="font-weight: bold; text-decoration: none;">edu/packages</del>/<del style="font-weight: bold; text-decoration: none;">dods/} </del>and/or contact <del style="font-weight: bold; text-decoration: none;">\xlink{User Support}{</del>mailto:support@<del style="font-weight: bold; text-decoration: none;">unidata</del>.<del style="font-weight: bold; text-decoration: none;">ucar.edu} </del>for help with this.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>#The DODS Project has developed two tools to help with serving datasets that contain many files. The first is to set up a `file server' a kind of catalog of URLs that is itself a DODS data set. The second is called the Aggregation Server (AS). The AS can automatically aggregate discrete datasets, accessed as either as files (in some cases) or URLs to produce a single data set. See the <ins style="font-weight: bold; text-decoration: none;">[</ins>http://<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org<cite>OPeNDAP Home<</ins>/<ins style="font-weight: bold; text-decoration: none;">cite>] </ins>and/or contact <ins style="font-weight: bold; text-decoration: none;">[</ins>mailto:support@<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org<cite>support</cite>] </ins>for help with this.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#When you're returning error messages, be sure to trim file pathnames so that the real path to data is hidden.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#When you're returning error messages, be sure to trim file pathnames so that the real path to data is hidden.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#If you have a data set and its API requires you to store a lot of state information that's not specific to a given variable or data type, consider creating a mixin class and making your data type children inherit from it in addition to the DAP classes. Because the `virtual contractors' are used to create instances of the data type classes, you can be sure that in your server, all instances of Byte, etc., contain the mixin. Use the <font color='green'>dynamic_cast</font> operator to access the mixin's methods.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#If you have a data set and its API requires you to store a lot of state information that's not specific to a given variable or data type, consider creating a mixin class and making your data type children inherit from it in addition to the DAP classes. Because the `virtual contractors' are used to create instances of the data type classes, you can be sure that in your server, all instances of Byte, etc., contain the mixin. Use the <font color='green'>dynamic_cast</font> operator to access the mixin's methods.</div></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1926&oldid=prevYuan: /* Notes */2008-01-26T15:29:06Z<p><span dir="auto"><span class="autocomment">Notes</span></span></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>==<del style="font-weight: bold; text-decoration: none;">Notes</del>==</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>==<ins style="font-weight: bold; text-decoration: none;">FootNotes</ins>==</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Here's a collection of information that might be important to specific</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Here's a collection of information that might be important to specific</div></td></tr>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>It's possible to replace the three separate programs, one for the DAS, DDS and DataDDS, with a single program. Clearly there all share close to 90\ either using the old Unix trick of making the programs symbolic links to a single executable and then checking to see which name was used to invoke it, or by modifying the dispatch script slightly to pass that information along with the other parameters.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>It's possible to replace the three separate programs, one for the DAS, DDS and DataDDS, with a single program. Clearly there all share close to 90\ either using the old Unix trick of making the programs symbolic links to a single executable and then checking to see which name was used to invoke it, or by modifying the dispatch script slightly to pass that information along with the other parameters.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>Similarly, you can subclass the DAS and DDS objects adding methods to them to build up the attributes and variables instead of writing functions to do that task.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>Similarly, you can subclass the DAS and DDS objects adding methods to them to build up the attributes and variables instead of writing functions to do that task.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>For complex data sets, it's likely that you'll need to create some new fields in the data type classes you specialized.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>For complex data sets, it's likely that you'll need to create some new fields in the data type classes you specialized.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>If you're writing a server that will principally be for internal use, or you expect many many small accesses, you should look into using the Java software or implementing your server as an Apache module. Contact support or the dods-tech email list for help with the latter.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>If you're writing a server that will principally be for internal use, or you expect many many small accesses, you should look into using the Java software or implementing your server as an Apache module. Contact support or the dods-tech email list for help with the latter.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>You can get help from the \xlink{DODS web site}{http://unidata.ucar.edu/packages/dods/}, the \xlink{dods-tech email list}{http://www.unidata.ucar.edu/packages/dods/home/mailLists/subscribe-dods-tech.html} and the \xlink{DODS user support desk}{mailto:support@unidata.ucar.edu}.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>You can get help from the \xlink{DODS web site}{http://unidata.ucar.edu/packages/dods/}, the \xlink{dods-tech email list}{http://www.unidata.ucar.edu/packages/dods/home/mailLists/subscribe-dods-tech.html} and the \xlink{DODS user support desk}{mailto:support@unidata.ucar.edu}.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>The DODS Project has developed two tools to help with serving datasets that contain many files. The first is to set up a `file server' a kind of catalog of URLs that is itself a DODS data set. The second is called the Aggregation Server (AS). The AS can automatically aggregate discrete datasets, accessed as either as files (in some cases) or URLs to produce a single data set. See the \xlink{DODS web page}{http://unidata.ucar.edu/packages/dods/} and/or contact \xlink{User Support}{mailto:support@unidata.ucar.edu} for help with this.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>The DODS Project has developed two tools to help with serving datasets that contain many files. The first is to set up a `file server' a kind of catalog of URLs that is itself a DODS data set. The second is called the Aggregation Server (AS). The AS can automatically aggregate discrete datasets, accessed as either as files (in some cases) or URLs to produce a single data set. See the \xlink{DODS web page}{http://unidata.ucar.edu/packages/dods/} and/or contact \xlink{User Support}{mailto:support@unidata.ucar.edu} for help with this.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>When you're returning error messages, be sure to trim file pathnames so that the real path to data is hidden.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>When you're returning error messages, be sure to trim file pathnames so that the real path to data is hidden.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">*</del>If you have a data set and its API requires you to store a lot of state information that's not specific to a given variable or data type, consider creating a mixin class and making your data type children inherit from it in addition to the DAP classes. Because the `virtual contractors' are used to create instances of the data type classes, you can be sure that in your server, all instances of Byte, etc., contain the mixin. Use the <font color='green'>dynamic_cast</font> operator to access the mixin's methods.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">#</ins>If you have a data set and its API requires you to store a lot of state information that's not specific to a given variable or data type, consider creating a mixin class and making your data type children inherit from it in addition to the DAP classes. Because the `virtual contractors' are used to create instances of the data type classes, you can be sure that in your server, all instances of Byte, etc., contain the mixin. Use the <font color='green'>dynamic_cast</font> operator to access the mixin's methods.</div></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1925&oldid=prevYuan: /* Implementing the DataDDS object */2008-01-26T15:27:55Z<p><span dir="auto"><span class="autocomment">Implementing the DataDDS object</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:27, 26 January 2008</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Also important is the call to <font color='green'>set_read_p()</font> with the value <font color='green'>true</font></div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Also important is the call to <font color='green'>set_read_p()</font> with the value <font color='green'>true</font></div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>this sets the <font color='green'>read_p</font> property<del style="font-weight: bold; text-decoration: none;">\footnote{The the `p' stands for</del></div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>this sets the <font color='green'>read_p</font> property<ins style="font-weight: bold; text-decoration: none;">(6) </ins>so that, should this function be run again</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">`Predicate'; maybe not the best naming convention given the prevalence of</del></div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div> </div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">pointers in <math>C++</math> software.} </del>so that, should this function be run again</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>while building this particular response, it will know the data have already</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>while building this particular response, it will know the data have already</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>been read.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>been read.</div></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1924&oldid=prevYuan: /* Implementing the DataDDS object */2008-01-26T15:25:48Z<p><span dir="auto"><span class="autocomment">Implementing the DataDDS object</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:25, 26 January 2008</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>While the Matlab server reads the entire array from the dataset and then</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>While the Matlab server reads the entire array from the dataset and then</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>applies the sub-sampling information, ''many'' data set types provide ways</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>applies the sub-sampling information, ''many'' data set types provide ways</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>to subsample variables through their own API (e.g., HDF, NetCDF, <del style="font-weight: bold; text-decoration: none;">\ldots</del>). In</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>to subsample variables through their own API (e.g., HDF, NetCDF, <ins style="font-weight: bold; text-decoration: none;">......</ins>). In</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>such cases, you'd read the CE information, then use it to read the data</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>such cases, you'd read the CE information, then use it to read the data</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>values. The most important point is that ''you don't always have to read</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>values. The most important point is that ''you don't always have to read</div></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1923&oldid=prevYuan: /* Implementing the DataDDS object */2008-01-26T15:25:16Z<p><span dir="auto"><span class="autocomment">Implementing the DataDDS object</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:25, 26 January 2008</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>to subsample variables through their own API (e.g., HDF, NetCDF, \ldots). In</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>to subsample variables through their own API (e.g., HDF, NetCDF, \ldots). In</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>such cases, you'd read the CE information, then use it to read the data</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>such cases, you'd read the CE information, then use it to read the data</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>values. The most important point is that <del style="font-weight: bold; text-decoration: none;">\emph{</del>you don't always have to read</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>values. The most important point is that <ins style="font-weight: bold; text-decoration: none;">''</ins>you don't always have to read</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>the entire variable from the data when using the DAP<del style="font-weight: bold; text-decoration: none;">}</del>. In fact, most</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>the entire variable from the data when using the DAP<ins style="font-weight: bold; text-decoration: none;">''</ins>. In fact, most</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>servers don't, they make sure to use the data set's underlying API in the</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>servers don't, they make sure to use the data set's underlying API in the</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>most efficient way possible, something that the DAP was designed to make</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>most efficient way possible, something that the DAP was designed to make</div></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1922&oldid=prevYuan: /* Implementing the DataDDS object */2008-01-26T15:24:22Z<p><span dir="auto"><span class="autocomment">Implementing the DataDDS object</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:24, 26 January 2008</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The <font color='green'>serialize()</font> method is broken into three parts:</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The <font color='green'>serialize()</font> method is broken into three parts:</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>*Read the data for this variable if that has not already been done. We'll see later that when <font color='green'>read()</font> successfully completes, it sets a boolean that the DAP library tests with the <font color='green'>read_p()</font> method. If <font color='green'>read_p()</font> returns <font color='green'>true</font> then data for this variable has already been read\footnote{In some cases, data for a variable is read while evaluating the constraint expression. So it can be the case that the</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>*Read the data for this variable if that has not already been done. We'll see later that when <font color='green'>read()</font> successfully completes, it sets a boolean that the DAP library tests with the <font color='green'>read_p()</font> method. If <font color='green'>read_p()</font> returns <font color='green'>true</font> then data for this variable has already been read\footnote{In some cases, data for a variable is read while evaluating the constraint expression. So it can be the case that the values for a variable are read before the <font color='green'>serialize()</font> method calls <font color='green'>read()</font>.}.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>values for a variable are read before the <font color='green'>serialize()</font> method calls</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>read()</font>.}.</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*Next the constraint expression (CE) is evaluated. The constraint expression was passed to the server as part of the DataDDS request. Parsing the CE and ensuring it's evaluated correctly is handled for you by the DAP library.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*Next the constraint expression (CE) is evaluated. The constraint expression was passed to the server as part of the DataDDS request. Parsing the CE and ensuring it's evaluated correctly is handled for you by the DAP library.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*Finally, if the CE evaluates to <font color='green'>true</font>, then we serialize the binary data that was read into this instance with the <font color='green'>read()</font> call at the beginning of this method.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>*Finally, if the CE evaluates to <font color='green'>true</font>, then we serialize the binary data that was read into this instance with the <font color='green'>read()</font> call at the beginning of this method.</div></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1921&oldid=prevYuan: /* Implementing the DataDDS object */2008-01-26T15:23:46Z<p><span dir="auto"><span class="autocomment">Implementing the DataDDS object</span></span></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:23, 26 January 2008</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The <font color='green'>serialize()</font> method is broken into three parts:</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The <font color='green'>serialize()</font> method is broken into three parts:</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>*Read the data for this variable if that has not already been done.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>*Read the data for this variable if that has not already been done. We'll see later that when <font color='green'>read()</font> successfully completes, it sets a boolean that the DAP library tests with the <font color='green'>read_p()</font> method. If <font color='green'>read_p()</font> returns <font color='green'>true</font> then data for this variable has already been read\footnote{In some cases, data for a variable is read while evaluating the constraint expression. So it can be the case that the</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>We'll see later that when <font color='green'>read()</font> successfully completes, it sets a</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>boolean that the DAP library tests with the <font color='green'>read_p()</font> method. If</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>read_p()</font> returns <font color='green'>true</font> then data for this variable has already been read\footnote{In some cases, data for a variable is read while</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>evaluating the constraint expression. So it can be the case that the</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>values for a variable are read before the <font color='green'>serialize()</font> method calls</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>values for a variable are read before the <font color='green'>serialize()</font> method calls</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>read()</font>.}.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>read()</font>.}.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>*Next the constraint expression (CE) is evaluated. The constraint</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>*Next the constraint expression (CE) is evaluated. The constraint expression was passed to the server as part of the DataDDS request. Parsing the CE and ensuring it's evaluated correctly is handled for you by the DAP library.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>expression was passed to the server as part of the DataDDS request. Parsing</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>*Finally, if the CE evaluates to <font color='green'>true</font>, then we serialize the binary data that was read into this instance with the <font color='green'>read()</font> call at the beginning of this method.</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>the CE and ensuring it's evaluated correctly is handled for you by the DAP</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>library.</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>*Finally, if the CE evaluates to <font color='green'>true</font>, then we serialize</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>the binary data that was read into this instance with the</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>read()</font> call at the beginning of this method.</div></td><td colspan="2" class="diff-side-added"></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1920&oldid=prevYuan: /* Implementing the DataDDS object */2008-01-26T15:22:50Z<p><span dir="auto"><span class="autocomment">Implementing the DataDDS object</span></span></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:22, 26 January 2008</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>each of the scalar, vector and constructor types has a method called</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>each of the scalar, vector and constructor types has a method called</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>serialize()</font>. Below is shown</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><font color='green'>serialize()</font>. Below is shown</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>[http://<del style="font-weight: bold; text-decoration: none;">www</del>.<del style="font-weight: bold; text-decoration: none;">unidata.ucar.edu/packages/dods</del>/api/pref<del style="font-weight: bold; text-decoration: none;">-</del>html/<del style="font-weight: bold; text-decoration: none;">Byte</del>.html<cite>Byte's</cite>] version of this method (Look at the code for</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>[http://<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org</ins>/api/pref<ins style="font-weight: bold; text-decoration: none;">/</ins>html/<ins style="font-weight: bold; text-decoration: none;">/classByte</ins>.html<cite>Byte's</cite>] version of this method (Look at the code for</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>[http://<del style="font-weight: bold; text-decoration: none;">www</del>.<del style="font-weight: bold; text-decoration: none;">unidata.ucar.edu/packages/dods</del>/api/pref<del style="font-weight: bold; text-decoration: none;">-</del>html/<del style="font-weight: bold; text-decoration: none;">DDS</del>.html<cite>DDS</cite>] if you'd like to see how <font color='green'>serialize()</font> is used and pay particular</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>[http://<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org</ins>/api/pref<ins style="font-weight: bold; text-decoration: none;">/</ins>html/<ins style="font-weight: bold; text-decoration: none;">/classDDS</ins>.html<cite>DDS</cite>] if you'd like to see how <font color='green'>serialize()</font> is used and pay particular</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>attention to <font color='green'>DDS::send_data()</font>).</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>attention to <font color='green'>DDS::send_data()</font>).</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
</table>Yuanhttps://docs.opendap.org/index.php?title=Writing_A_Server&diff=1919&oldid=prevYuan: /* Implementing the DAS object */2008-01-26T15:21:52Z<p><span dir="auto"><span class="autocomment">Implementing the DAS object</span></span></p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 15:21, 26 January 2008</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l853">Line 853:</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>If the variable is not a string, then the Matlab server creates an empty</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>If the variable is not a string, then the Matlab server creates an empty</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>attribute table for it. This is to conform to the <del style="font-weight: bold; text-decoration: none;">\xlink{DAP 2.0 draft specification}{</del>http://www.<del style="font-weight: bold; text-decoration: none;">unidata</del>.<del style="font-weight: bold; text-decoration: none;">ucar.edu/packages/dods</del>/<del style="font-weight: bold; text-decoration: none;">design</del>/<del style="font-weight: bold; text-decoration: none;">dap</del>-<del style="font-weight: bold; text-decoration: none;">rfc</del>-<del style="font-weight: bold; text-decoration: none;">html</del>/<del style="font-weight: bold; text-decoration: none;">dap_32.html}</del></div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>attribute table for it. This is to conform to the <ins style="font-weight: bold; text-decoration: none;">[</ins>http://www.<ins style="font-weight: bold; text-decoration: none;">opendap</ins>.<ins style="font-weight: bold; text-decoration: none;">org</ins>/<ins style="font-weight: bold; text-decoration: none;">pdf</ins>/<ins style="font-weight: bold; text-decoration: none;">ESE</ins>-<ins style="font-weight: bold; text-decoration: none;">RFC</ins>-<ins style="font-weight: bold; text-decoration: none;">004v1.1.pdf<cite>DAP 2.0 draft specification<</ins>/<ins style="font-weight: bold; text-decoration: none;">cite>]</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>which states that all variable must have an attribute table, even if it is</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>which states that all variable must have an attribute table, even if it is</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>empty.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>empty.</div></td></tr>
</table>Yuan