Adding a strategy for saving newly added or modified features. Setting the auto property to true gives you auto-saves with every addition/modification. Setting auto to a time (in seconds) gives periodic auto-save of all new/modified features. By default, the save method must be called to trigger save. r=ahocevar (closes #1924)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@8818 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers.js

@@ -188,6 +188,7 @@
             "OpenLayers/Strategy/Cluster.js",
             "OpenLayers/Strategy/Paging.js",
             "OpenLayers/Strategy/BBOX.js",
+            "OpenLayers/Strategy/Save.js",
             "OpenLayers/Protocol.js",
             "OpenLayers/Protocol/HTTP.js",
             "OpenLayers/Protocol/SQL.js",

lib/OpenLayers/Strategy/Save.js

@@ -0,0 +1,194 @@
+/* Copyright (c) 2006-2008 MetaCarta, Inc., published under the Clear BSD
+ * license.  See http://svn.openlayers.org/trunk/openlayers/license.txt for the
+ * full text of the license. */
+
+/**
+ * @requires OpenLayers/Strategy.js
+ */
+
+/**
+ * Class: OpenLayers.Strategy.Save
+ * A strategy that commits newly created or modified features.  By default
+ *     the strategy waits for a call to <save> before persisting changes.  By
+ *     configuring the strategy with the <auto> option, changes can be saved
+ *     automatically.
+ *
+ * Inherits from:
+ *  - <OpenLayers.Strategy>
+ */
+OpenLayers.Strategy.Save = OpenLayers.Class(OpenLayers.Strategy, {
+    
+    /**
+     * APIProperty: auto
+     * {Boolean | Number} Auto-save.  Default is false.  If true, features will be
+     *     saved immediately after being added to the layer and with each
+     *     modification or deletion.  If auto is a number, features will be
+     *     saved on an interval provided by the value (in seconds).
+     */
+    auto: false,
+    
+    /**
+     * Property: timer
+     * {Number} The id of the timer.
+     */
+    timer: null,
+
+    /**
+     * Constructor: OpenLayers.Strategy.Save
+     * Create a new Save strategy.
+     *
+     * Parameters:
+     * options - {Object} Optional object whose properties will be set on the
+     *     instance.
+     */
+    initialize: function(options) {
+        OpenLayers.Strategy.prototype.initialize.apply(this, [options]);
+    },
+   
+    /**
+     * APIMethod: activate
+     * Activate the strategy.  Register any listeners, do appropriate setup.
+     * 
+     * Returns:
+     * {Boolean} The strategy was successfully activated.
+     */
+    activate: function() {
+        var activated = OpenLayers.Strategy.prototype.activate.call(this);
+        if(activated) {
+            if(this.auto) {
+                if(typeof this.auto === "number") {
+                    this.timer = window.setInterval(
+                        OpenLayers.Function.bind(this.save, this),
+                        this.auto * 1000
+                    )
+                } else {
+                    this.layer.events.on({
+                        "featureadded": this.triggerSave,
+                        "afterfeaturemodified": this.triggerSave,
+                        scope: this
+                    });
+                }
+            }
+        }
+        return activated;
+    },
+    
+    /**
+     * APIMethod: deactivate
+     * Deactivate the strategy.  Unregister any listeners, do appropriate
+     *     tear-down.
+     * 
+     * Returns:
+     * {Boolean} The strategy was successfully deactivated.
+     */
+    deactivate: function() {
+        var deactivated = OpenLayers.Strategy.prototype.deactivate.call(this);
+        if(deactivated) {
+            if(this.auto) {
+                if(typeof this.auto === "number") {
+                    window.clearInterval(this.timer);
+                } else {
+                    this.layer.events.un({
+                        "featureadded": this.triggerSave,
+                        "afterfeaturemodified": this.triggerSave,
+                        scope: this
+                    })
+                }
+            }
+        }
+        return deactivated;
+    },
+    
+    /**
+     * Method: triggerSave
+     * Registered as a listener.  Calls save if a feature has insert, update,
+     *     or delete state.
+     *
+     * Parameters:
+     * event - {Object} The event this function is listening for.
+     */
+    triggerSave: function(event) {
+        var feature = event.feature;
+        if(feature.state === OpenLayers.State.INSERT ||
+           feature.state === OpenLayers.State.UPDATE ||
+           feature.state === OpenLayers.State.DELETE) {
+            this.save([event.feature]);
+        }
+    },
+    
+    /**
+     * Method: save
+     * Tell the layer protocol to commit unsaved features.  If the layer
+     *     projection differs from the map projection, features will be
+     *     transformed into the layer projection before being committed.
+     *
+     * Parameters:
+     * features - {Array} Features to be saved.  If null, then default is all
+     *     features in the layer.  Features are assumed to be in the map
+     *     projection.
+     */
+    save: function(features) {
+        if(!features) {
+            features = this.layer.features;
+        }
+        var remote = this.layer.projection;
+        var local = this.layer.map.getProjectionObject();
+        if(!local.equals(remote)) {
+            var len = features.length;
+            var clones = new Array(len);
+            var orig, clone;
+            for(var i=0; i<len; ++i) {
+                orig = features[i];
+                clone = orig.clone();
+                clone.fid = orig.fid;
+                clone.state = orig.state;
+                clone._original = orig;
+                clone.geometry.transform(local, remote);
+                clones[i] = clone;
+            }
+            features = clones;
+        }
+        this.layer.protocol.commit(features, {
+            callback: this.onCommit,
+            scope: this
+        });
+    },
+    
+    /**
+     * Method: onCommit
+     * Called after protocol commit.
+     *
+     * Parameters:
+     * response - {<OpenLayers.Protocol.Response>} A response object.
+     */
+    onCommit: function(response) {
+        if(response.success()) {
+            var features = response.reqFeatures;
+            // deal with inserts, updates, and deletes
+            var state, feature;
+            var destroys = [];
+            var insertIds = response.insertIds || [];
+            var j = 0;
+            for(var i=0, len=features.length; i<len; ++i) {
+                feature = features[i];
+                // if projection was different, we may be dealing with clones
+                feature = feature._original || feature;
+                state = feature.state;
+                if(state) {
+                    if(state == OpenLayers.State.DELETE) {
+                        destroys.push(feature);
+                    } else if(state == OpenLayers.State.INSERT) {
+                        feature.fid = insertIds[j];
+                        ++j;
+                    }
+                    feature.state = null;
+                }
+            }
+            if(destroys.length > 0) {
+                this.layer.destroyFeatures(destroys);
+            }
+        }
+    },    
+   
+    CLASS_NAME: "OpenLayers.Strategy.Save" 
+});

tests/Strategy/Save.html

@@ -0,0 +1,108 @@
+<html>
+<head>
+  <script src="../../lib/OpenLayers.js"></script>
+  <script type="text/javascript">
+  
+    function test_initialize(t) {
+        t.plan(1);
+        var strategy = new OpenLayers.Strategy.Save();
+        t.eq(strategy.auto, false, "auto is false by default");
+    }
+
+    function test_activate(t) {
+        
+        t.plan(3);
+        
+        var strategy = new OpenLayers.Strategy.Save();
+        var layer = new OpenLayers.Layer.Vector(null, {
+            isBaseLayer: true,
+            protocol: new OpenLayers.Protocol(),
+            strategies: [strategy]
+        });
+        var map = new OpenLayers.Map("map");
+        map.addLayer(layer);
+        map.zoomToMaxExtent();
+        
+        // check that auto true registers listeners
+        strategy.deactivate();
+        strategy.auto = true;
+        strategy.activate();
+        t.ok(layer.events.listeners["featureadded"][0].func === strategy.triggerSave,
+             "[auto true] triggerSave registered as listener for featureadded");
+        t.ok(layer.events.listeners["afterfeaturemodified"][0].func === strategy.triggerSave,
+             "[auto true] triggerSave registered as listener for afterfeaturemodified");
+
+        // check that auto can be set to interval
+        strategy.deactivate();
+        strategy.auto = 1;
+        strategy.activate();
+        t.ok(strategy.timer != null, "[auto number] timer set")
+        
+        map.destroy();
+        
+    }
+    
+    function test_save(t) {
+        t.plan(5);
+
+        var strategy = new OpenLayers.Strategy.Save();
+        
+        // mock up a protocol for synchronous and successful commits
+        var protocol = new OpenLayers.Protocol({
+            commit: function(features, options) {
+                var response = new OpenLayers.Protocol.Response();
+                response.reqFeatures = features;
+                response.insertIds = [];
+                for(var i=0; i<features.length; ++i) {
+                    if(features[i].state == OpenLayers.State.INSERT) {
+                        response.insertIds.push("new_" + i);
+                    }
+                }
+                response.code = OpenLayers.Protocol.Response.SUCCESS;
+                options.callback.call(options.scope, response);
+            }
+        });
+
+        var layer = new OpenLayers.Layer.Vector(null, {
+            isBaseLayer: true,
+            protocol: protocol,
+            strategies: [strategy]
+        });
+        var map = new OpenLayers.Map("map");
+        map.addLayer(layer);
+        map.zoomToMaxExtent();
+        
+        // give the layer some features
+        var features = [
+            new OpenLayers.Feature.Vector(), // insert
+            new OpenLayers.Feature.Vector(), // delete
+            new OpenLayers.Feature.Vector(), // update
+            new OpenLayers.Feature.Vector()  // nothing
+        ];
+        features[0].state = OpenLayers.State.INSERT;
+        features[1].state = OpenLayers.State.DELETE;
+        features[2].state = OpenLayers.State.UPDATE;
+        layer.addFeatures(features);
+        
+        // save feature modifications
+        strategy.save(features);
+        
+        // confirm that newly created feature has an id and no longer has insert state
+        t.eq(features[0].fid, "new_0", "newly created feature gets fid");
+        t.ok(features[0].state == null, "newly created feature no longer insert state");
+        
+        // confirm that deleted features are not on layer
+        t.eq(layer.features.length, 3, "layer only has three features");
+        t.ok(features[1].layer == null, "deleted feature has no layer");
+        
+        // confirm that updated feature no longer has update state
+        t.ok(features[2].state == null, "updated feature no longer update state");
+        
+    }
+
+  </script>
+</head>
+<body>
+    <div id="map" style="width: 400px; height: 200px" />
+</body>
+</html>

tests/list-tests.html

@@ -133,6 +133,7 @@
     <li>Strategy/Cluster.html</li>
     <li>Strategy/Fixed.html</li>
     <li>Strategy/Paging.html</li>
+    <li>Strategy/Save.html</li>
     <li>Style.html</li>
     <li>StyleMap.html</li>
     <li>Tile.html</li>