WCS URI description, fixes

Author: blazek

python/core/qgsdatasourceuri.sip

@@ -29,6 +29,41 @@ public:
 
   //! quoted table name
   QString quotedTablename() const;
+
+  //! return complete encoded uri (generic mode)
+  // \note added in 1.9
+  QByteArray encodedUri() const;
+
+  //! set complete encoded uri (generic mode)
+  // \note added in 1.9
+  void setEncodedUri( const QByteArray & uri );
+
+  //! set complete encoded uri (generic mode)
+  // \note added in 1.9
+  void setEncodedUri( const QString & uri );
+
+  //! Set generic param (generic mode)
+  // \note if key exists, another is inserted
+  // \note added in 1.9
+  void setParam( const QString &key, const QString &value );
+  void setParam( const QString &key, const QStringList &value );
+
+  //! Remove generic param (generic mode)
+  // \note remove all occurrences of key, returns number of params removed
+  // \note added in 1.9
+  int removeParam( const QString &key );
+
+  //! Get generic param (generic mode)
+  // \note added in 1.9
+  QString param( const QString &key ) const;
+
+  //! Get multiple generic param (generic mode)
+  // \note added in 1.9
+  QStringList params( const QString &key ) const;
+
+  //! Test if param exists (generic mode)
+  // \note added in 1.9
+  bool hasParam( const QString &key ) const;
 
   //! Set all connection related members at once
   //! \note This optional sslmode parameter has been added in version 1.1

src/providers/wcs/URI

@@ -0,0 +1,41 @@
+                        WCS URI
+                        -------
+
+Example: url=http://127.0.0.1/wcs&identifier=coverage1
+
+WCS URI is composed of key=value pairs separated by '&'. It is the same format like query string in URL, encoded the same way. QgsDataSourceURI should be used to construct the URI to ensure that special characters are encoded properly.
+
+Parameters:
+
+* url (required) : WCS Server URL. Do not use VERSION in URL, because each version of WCS is using different parameter name for GetCapabilities version, see param version.
+
+* identifier (required) : Coverage name
+
+* format: (optional) : Supported format name. Default is the first supported format with tif in name or the first supported format.
+
+* crs (optional) : CRS in form AUTHORITY:ID, e.g. EPSG:4326. Default is EPSG:4326 if supported or the first supported CRS.
+
+* username (optional) : Username for basic authentication.
+
+* password (optional) : Password for basic authentication.
+
+* IgnoreGetMapUrl (optional,hack) : If specified (set to 1), ignore GetCoverage URL advertised by GetCapabilities. May be necessary if a server is not configured properly.
+
+* InvertAxisOrientation (optional,hack) : If specified (set to 1), switch axis in GetCoverage request. May be necessary for geographic CRS if a server is using wrong axis order.
+
+* IgnoreAxisOrientation (optional,hack) : If specified (set to 1), do not invert axis orientation according to WCS standard for geographic CRS.
+
+
+Python console example:
+
+from PyQt4.QtCore import QString
+
+uri = QgsDataSourceURI()
+uri.setParam ("url", "http://wcs.qgis.org/1.9.0/wcs" )
+uri.setParam ( "identifier", "band1_int16_noct_epsg4326" )
+
+layer = QgsRasterLayer( QString(uri.encodedUri()), "WCS test", "wcs" )
+layer.isValid()
+
+QgsMapLayerRegistry.instance().addMapLayer(layer)
+

src/providers/wcs/qgswcsprovider.cpp

@@ -71,7 +71,7 @@ QgsWcsProvider::QgsWcsProvider( QString const &uri )
     : QgsRasterDataProvider( uri )
     , QgsGdalProviderBase()
     , mHttpUri( QString::null )
-    , mCoverageCrs( DEFAULT_LATLON_CRS )
+    , mCoverageCrs()
     , mCacheReply( 0 )
     , mCachedViewExtent( 0 )
     , mCoordinateTransform( 0 )
@@ -143,18 +143,27 @@ QgsWcsProvider::QgsWcsProvider( QString const &uri )
 
   // It could happen (usually not with current QgsWCSSourceSelect if at least
   // one CRS is available) that crs is not set in uri, in that case we
-  // use the native, if available, or the first supported
+  // use the native, if available or WGS84 or the first supported
   if ( mCoverageCrs.isEmpty() )
   {
+    QgsDebugMsg( "nativeCrs = " + mCoverageSummary.nativeCrs );
+    QgsDebugMsg( "supportedCrs = " + mCoverageSummary.supportedCrs.join( "," ) );
     if ( !mCoverageSummary.nativeCrs.isEmpty() )
     {
       setCoverageCrs( mCoverageSummary.nativeCrs );
     }
+    else if ( mCoverageSummary.supportedCrs.contains( "EPSG:4326", Qt::CaseInsensitive ) )
+    {
+      setCoverageCrs( "EPSG:4326" );
+    }
     else if ( mCoverageSummary.supportedCrs.size() > 0 )
     {
       setCoverageCrs( mCoverageSummary.supportedCrs.value( 0 ) );
     }
   }
+  QgsDebugMsg( "mCoverageCrs = " + mCoverageCrs );
+  // We cannot continue without CRS
+  if ( mCoverageCrs.isEmpty() ) return;
 
   mWidth = mCoverageSummary.width;
   mHeight = mCoverageSummary.height;
@@ -350,9 +359,10 @@ bool QgsWcsProvider::parseUri( QString uriString )
 
   setFormat( uri.param( "format" ) );
 
-  // TODO: if not defined, use the best available, probably EPSG:4326
-  setCoverageCrs( uri.param( "crs" ) );
-  mCrs.createFromOgcWmsCrs( uri.param( "crs" ) );
+  if ( !uri.param( "crs" ).isEmpty() )
+  {
+    setCoverageCrs( uri.param( "crs" ) );
+  }
 
   return true;
 }
@@ -424,6 +434,8 @@ void QgsWcsProvider::setCoverageCrs( QString const & crs )
     mExtentDirty = true;
 
     mCoverageCrs = crs;
+
+    mCrs.createFromOgcWmsCrs( mCoverageCrs );
   }
 }
 

tests/src/providers/CMakeLists.txt

@@ -23,7 +23,7 @@ ADD_DEFINITIONS(-DTEST_DATA_DIR="\\"${TEST_DATA_DIR}\\"")
 
 ADD_DEFINITIONS(-DINSTALL_PREFIX="\\"${CMAKE_INSTALL_PREFIX}\\"")
 
-SET(TEST_SERVER_URL "http://127.0.0.1/test/${COMPLETE_VERSION}")
+SET(TEST_SERVER_URL "http://wcs.qgis.org/${COMPLETE_VERSION}")
 ADD_DEFINITIONS(-DTEST_SERVER_URL="\\"${TEST_SERVER_URL}\\"")
 
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