- DATASTREAM values are refer to datastreams of the object(s) the mechanism will be bound to. They must always be passed by URL-REF, which means you cannot directly access the datastream's value, even if it is just a short string. Contrary to what the Admin tool help system says, you can use DATASTREAM references in a mechanism even though you have defined the mechanism as being "Multi-Server Service".
- DEFAULT values are defined within the mechanism. They are always passed by VALUE, since the data you want entered in the URL is the data you entered. (You could have pasted this information directly into the URL, but that would make it much more difficult to read.) Note: Don't declare a default value that points to Fedora on the local server, because this value won't be updated when the object is moved to another repository. Instead, just put the value directly in the service URL.
- USER values must be passed from elsewhere, as part of the URL that calls the dissemination. For an example, see the URL that is created when you use one of the demo image manipulation methods. Note that USER values must be defined in the behavior definition, and have the same name there as they do in the behavior mechanism.
The most frequently used service is Saxon:
http://\[hostname\]:\[portNumber\]/saxon/SaxonServlet?source=\[xmlSource\]&style=\[xslStylesheet\]&clear-stylesheet-cache=yes Wiki Markup
BMech Tricks and Tips
To pass an object's PID, declare the parameter to be type DEFAULT, but use the default value "$pid" (without quotes). To pass a PID in URI form, use the default value "$objuri".