ServerDispatchOperations
Now that Hyrax has been released it has become clear that we need to publish a paper that describes the correct behavior of an OPENDAP server. This should include the details of:
- Dispatch - How the various request URL's get assessed and which responses are sent.
- Errors - Which errors should be associated with which dispatch paths.
URL Dispatch Operations
OPeNDAP servers provide an interface through which clients can access data held on there server. The server can provide sub-setting and, in some cases, additional preprocessing operations on the requested data. The protocol through which the OPeNDAP server s provide these data services is called the Data Access Protocol (DAP). The current version of the DAP is version 2, so The DAP is usually specified as DAP2.
In addition to DAP2 responses, most OPeNDAP servers provide a number of additional services such as:
- A navigation interface for browsing the data storage hierarchy.
- File access.
- Version reporting.
- Help pages and other documentation.
- THREDDS catalog views of the data system.
Dispatch is the process in which:
- An OPeNDAP server receives a request (that comes in the form of a URL).
- The server evaluates the URL to determine what type of response the URL indicates the server should provide.
- Providing the requested response if possible, or returning the appropriate error (in the appropriate format) if the request cannot be fulfilled.
Special Requests
Hyrax and other servers may support some special requests. These may be a secure server administration interface, help information, server status, or system properties. There is no clearly defined set of special responses, and their implementation is left up to the various server developers.
Hyrax currently supports:
- help - The URL http://your.host:port/opendap/help will take you to an help web page.
