Publish API

11.6 Publish API

You can programmatically create new entries on a RAMADDA server. There is a Java class, ucar.unidata.repository.RepositoryClient, that provides some of the facilities. You can also look at the ucar.unidata.repository.idv.RamaddaPublisher which is used within the IDV to publish content to RAMADDA. This class uses the ucar.unidata.repository.InteractiveRepositoryClient class that provides some GUI facilities (e.g., a group JTree component).

Lets say you want to upload a file (e.g., test.png) to RAMADDA. First you need to establish a session with RAMADDA. You can just do a url get with:

http://<server>/repository/user/login?output=xml&user.password=<password>&user.id=<user>

The output=xml tells RAMADDA to return the result as xml.

The above request returns xml of the form:

<response code="ok">
sessionid
</response>

Or if there was an error:

<response code="error">
some error message
</response>

Subsequent posts to RAMADDA just require an extra argument:

sessionid=<sessionid>

You can also use RepositoryClient code:

  RepositoryClient client = new RepositoryClient(server, 80, "/repository", userId,password);
  String[] msg = { "" };
  if (client.isValidSession(true, msg)) {
       System.err.println("Valid session");
   } else {
        System.err.println("Invalid session:" + msg[0]);
   }

Next, create an xml file that defines the entries you want to create.

 <entries>
  <entry name="test.png" 
            description=""  
            type="file" 
            id="0" 
            file="test.png"  
            parent="0/0" 
            south="-7.926" 
            west="-198.358"
            north="71.864" 
            east="-3.950"
            fromdate="2008-08-19 16:01:00 GMT"
            todate="2008-08-19 16:01:00 GMT" 

</entries>

The type attribute is the data types available in RAMADDA. Its best to stay with file and group.
The parent is the actual parent id in RAMADDA.
The fromdata, todate, south, west, east, north and description are all optional.

The id attribute will not be the actual id of the entry but allows you to reference the entries elsewhere. For example, you could create a group entry and then another entry that is a child of the group:

 <entries>
  <entry name="Some group" 
            id="0"
            parent="0/0" 
            type="group"  />

  <entry name="test.png" 
            description=""  
            type="file" 
            id="1" 
            file="test.png"  
            parent="0"  />
</entries>

Now, zip up this xml file along with the file you want to upload and then post the zipped file to:

http://<server>/repository/entry/xmlcreate

Include the arguments:

output=xml
sessionid=<sessionid>
file=thezipfile

If you are not uploading files you can just post the xml file instead of the zip file. In that case instead of a file= attribute in the xml use url=, e.g.,:

 <entries>
  <entry name="Some opendap url" 
            type="file" 
            id="0" 
            url="the opendap url"  
            parent="0/0" 
</entries>

Either way, you will get back the response xml with either code=ok and a list of the entry ids created:

<response code="ok">
  <entry id="1219161636252_0.6145187911490728_17"/>
</response>

Or an error response:

<response code="error">
error message
</response>

Here is a longer version of an entries file:

<entries>
  <entry description="" east="-3.950" file="test.xidv" fromdate="2008-08-19 16:01:00 GMT" id="0" name="test.png" north="71.864" parent="0/0" south="-7.926" todate="2008-08-19 16:01:00 GMT" type="file" west="-198.358"/>
  <entry east="-3.950" file="test.png" fromdate="2008-08-19 16:01:00 GMT" id="1" name="test.png - Product" north="71.864" parent="0/0" south="-7.926" todate="2008-08-19 16:01:00 GMT" type="file" west="-198.358"/>
  <association from="0" name="generated product" to="1"/>
</entries>

With its response:

<response code="ok">
  <entry id="1219161636252_0.5912686911125428_33"/>
  <entry id="1219161636252_0.34475975368841827_34"/>
  <association id="1219161636252_0.18087075533515407_35"/>
</response>