Add a ol.source.WMTS.createFromCapabilities function

so that we can create a wmts source directly from a getCapabilities response (parsed by the wmts parser)
2013-03-07 22:22:36 +01:00
parent dc440a6604
commit 13d0b36a08
3 changed files with 161 additions and 0 deletions
--- a/src/ol/source/wmtssource.js
+++ b/src/ol/source/wmtssource.js
@@ -166,3 +166,133 @@ ol.source.WMTS = function(wmtsOptions) {

 };
 goog.inherits(ol.source.WMTS, ol.source.ImageTileSource);
+
+
+/**
+ * @param {Object} wmtsCap An object representing the capabilities document.
+ * @param {string} layer The layer identifier that we want the grid for.
+ * @param {string|null=} opt_crossOrigin Optional crossOrigin value.
+ * @param {string=} opt_matrixSet Optional tileMatrixSet name. If not provided,
+ *     it defaults to the first matrixSet found.
+ * @param {ol.source.WMTSRequestEncoding=} opt_requestEncoding Optional
+ *     requestEncoding. If not provided, it defaults to the first value found.
+ * @param {string=} opt_format Optional format name. If not provided, it
+ *     defaults to the first format found.
+ * @param {string=} opt_style Optional style name. If not provided, it defaults
+ *     to the first style found.
+ * @param {Object=} opt_dimensions Optional object for setting dimensions
+ *     values.
+ * @param {ol.Extent=} opt_extent Optional extent.
+ * @return {ol.source.WMTS} TileGrid instance.
+ */
+ol.source.WMTS.createFromCapabilities = function(wmtsCap, layer,
+    opt_crossOrigin, opt_matrixSet, opt_requestEncoding, opt_format,
+    opt_style, opt_dimensions, opt_extent) {
+
+  // TODO: add support for TileMatrixLimits
+
+  var layers = wmtsCap['contents']['layers'];
+  var matrixSet = opt_matrixSet;
+  var l = goog.array.find(layers, function(elt, index, array) {
+    return elt['identifier'] == layer;
+  });
+  goog.asserts.assert(!goog.isNull(l));
+
+  var format = goog.isDef(opt_format) ?
+      opt_format : /** @type {string} */ (l['formats'][0]);
+  var idx = goog.array.findIndex(l['styles'], function(elt, index, array) {
+    if (goog.isDef(opt_style)) {
+      return elt['identifier'] == opt_style;
+    } else {
+      return elt['isDefault'];
+    }
+  });
+  if (idx < 0) {
+    goog.asserts.assert(!goog.isDef(opt_style)); // opt_style was not correct
+    idx = 0;
+  }
+  var style = /** @type {string} */ (l['styles'][idx]['identifier']);
+
+  var dimensions = {};
+  goog.array.forEach(l['dimensions'], function(elt, index, array) {
+    var key = elt['identifier'];
+    // With the special value 'default', the server should automatically
+    // select the default value for this dimension.
+    var value = (goog.isDef(opt_dimensions) &&
+        opt_dimensions.hasOwnProperty(key)) ?
+            opt_dimensions[key] : elt['default'];
+    if (goog.isDef(value)) {
+      goog.asserts.assert(goog.array.indexOf(elt['values'], value) >= 0);
+    } else {
+      value = elt['values'][0];
+    }
+    goog.asserts.assert(goog.isDef(value));
+    dimensions[key] = value;
+  });
+
+  if (goog.isDef(matrixSet)) {
+    goog.asserts.assert(0 < goog.array.findIndex(
+        l['tileMatrixSetLinks'], function(elt, index, arr) {
+          return elt['tileMatrixSet'] == matrixSet;
+        }));
+  } else {
+    goog.asserts.assert(l['tileMatrixSetLinks'].length > 0);
+    matrixSet = /** @type {string} */
+        (l['tileMatrixSetLinks'][0]['tileMatrixSet']);
+  }
+  var matrixSets = wmtsCap['contents']['tileMatrixSets'];
+  goog.asserts.assert(matrixSet in matrixSets);
+  var matrixSetObj = matrixSets[matrixSet];
+
+  var tileGrid = ol.tilegrid.WMTS.createFromCapabilitiesMatrixSet(
+      matrixSetObj);
+
+  var projection = ol.projection.get(matrixSetObj['supportedCRS']);
+
+  var gets = wmtsCap['operationsMetadata']['GetTile']['dcp']['http']['get'];
+  var encodings = goog.object.getKeys(
+      gets[0]['constraints']['GetEncoding']['allowedValues']);
+  goog.asserts.assert(encodings.length > 0);
+  var requestEncoding = goog.isDef(opt_requestEncoding) ?
+      opt_requestEncoding :  /** @type {ol.source.WMTSRequestEncoding} */
+      (encodings[0]);
+  // TODO: arcgis support, quote from ol2:
+  // The OGC documentation is not clear if we should use REST or RESTful,
+  // ArcGis use RESTful, and OpenLayers use REST.
+
+  var urls;
+  switch (requestEncoding) {
+    case ol.source.WMTSRequestEncoding.REST:
+      goog.asserts.assert(l['resourceUrls'].hasOwnProperty('tile'));
+      goog.asserts.assert(l['resourceUrls']['tile'].hasOwnProperty(format));
+      urls = /** @type {Array.<string>} */
+          (l['resourceUrls']['tile'][format]);
+      break;
+    case ol.source.WMTSRequestEncoding.KVP:
+      urls = [];
+      goog.array.forEach(gets, function(elt, index, array) {
+        if (elt['constraints']['GetEncoding']['allowedValues'].hasOwnProperty(
+            ol.source.WMTSRequestEncoding.KVP)) {
+          urls.push(/** @type {string} */ (elt['url']));
+        }
+      });
+      goog.asserts.assert(urls.length > 0);
+      break;
+    default:
+      goog.asserts.assert(false);
+  }
+
+  return new ol.source.WMTS({
+    urls: urls,
+    layer: layer,
+    matrixSet: matrixSet,
+    format: format,
+    projection: projection,
+    requestEncoding: requestEncoding,
+    tileGrid: tileGrid,
+    style: style,
+    crossOrigin: opt_crossOrigin,
+    extent: opt_extent,
+    dimensions: dimensions
+  });
+};