[Pywps-commits] r1002 - trunk/doc/source/clients

[scm-commit@wald.intevation.org]

Author: jachym
Date: 2010-09-01 13:07:53 +0200 (Wed, 01 Sep 2010)
New Revision: 1002

Modified:
   trunk/doc/source/clients/javascript.rst
Log:
more documentation from Luca

Modified: trunk/doc/source/clients/javascript.rst
===================================================================
--- trunk/doc/source/clients/javascript.rst	2010-08-31 22:04:23 UTC (rev 1001)
+++ trunk/doc/source/clients/javascript.rst	2010-09-01 11:07:53 UTC (rev 1002)
@@ -4,7 +4,7 @@
 `OpenLayers <http://openlayers.org>`_. The client *does not show any
 results in the map*, but it enables you, as client coder, to program the
 client in hopefully easy way. The client is located in
-:file:`pywps-source/webclient/WPS.js`. Beside this file, OpenLayers have to
+:file:`PyWPS-source/webclient/WPS.js`. Beside this file, OpenLayers have to
 be included in the web page.
 
 Initialization and GetCapabilities request
@@ -215,3 +215,60 @@
     };
 
 The rest was already defined before.
+
+Handling vector data 
+......................................................
+A typical operation performed using OpenLayers and a WPS service,
+is to send data to the server and display the results directly over the map.
+For example consider a process that allows to generate a buffer starting from
+vector data and a number to use as buffer's value. From the DescribeProcess we 
+see that those two inputs must be passed as "data" and "buffer".
+At this point we start with the configuration of OpenLayers:
+
+Add vector layer used for editing and the editing toolbar control:
+
+.. code-block:: javascript
+
+    vlayer = new OpenLayers.Layer.Vector("Editable");
+    edit = new OpenLayers.Control.EditingToolbar(vlayer);
+    map.addControl(edit);
+
+Now create the WPS object as defined before;a bit of attention to input/output parameters
+because we're going to use the featues drawn by the user (vlayer) and a literaldata inserted 
+in a HTML text box with buffer as id.
+
+Input:
+.. code-block:: javascript
+
+    var dataInput = new OpenLayers.WPS.ComplexPut({
+        identifier:"data",
+        value:  OpenLayers.Format.GML.prototype.write(vlayer.features)
+    });
+
+    var literalInput = new OpenLayers.WPS.LiteralPut({
+        identifier:"buffer",
+        value: document.getElementById("buffer").value
+    });
+
+Ouput:
+
+..code-block:: javascript
+    var complexOutput = new OpenLayers.WPS.ComplexPut({
+        identifier: "output",
+        asReference: "true"
+    });
+    
+Now move to the onSuceedeed function, the one executed once the process has successfully run.
+Basically we need to add the output file to the list of layers in the map object. OpenLayers 
+allows to add GML directly on the map, but watch out for file too big:
+
+..code-block:: javascript
+    var onWPSSussceeded = function(process) {
+		//We need to remove the layer generated by previous instance of the script
+	    try {
+		    map.removeLayer(rlayer);
+	        rlayer.destroy();
+		} catch(e) {}
+	    	url = process.getOutput("output").value;
+		    rlayer = new OpenLayers.Layer.GML("Result",url);
+	    	Pap.addLayer(rlayer);