Add method for QgsNetworkContentFetcher to fetch using request instea…

…d of url

python/core/qgsnetworkcontentfetcher.sip.in

@@ -40,6 +40,14 @@ Fetches content from a remote URL and handles redirects. The finished()
 signal will be emitted when content has been fetched.
 
 :param url: URL to fetch
+%End
+
+    void fetchContent( const QNetworkRequest &request );
+%Docstring
+Fetches content using a network ``request`` and handles redirects. The finished()
+signal will be emitted when content has been fetched.
+
+.. versionadded:: 3.2
 %End
 
     QNetworkReply *reply();

src/core/qgsnetworkcontentfetcher.cpp

@@ -38,10 +38,12 @@ QgsNetworkContentFetcher::~QgsNetworkContentFetcher()
 
 void QgsNetworkContentFetcher::fetchContent( const QUrl &url )
 {
-  mContentLoaded = false;
+  fetchContent( QNetworkRequest( url ) );
+}
 
-  //get contents
-  QNetworkRequest request( url );
+void QgsNetworkContentFetcher::fetchContent( const QNetworkRequest &request )
+{
+  mContentLoaded = false;
 
   if ( mReply )
   {

src/core/qgsnetworkcontentfetcher.h

@@ -54,6 +54,14 @@ class CORE_EXPORT QgsNetworkContentFetcher : public QObject
      */
     void fetchContent( const QUrl &url );
 
+    /**
+     * Fetches content using a network \a request and handles redirects. The finished()
+     * signal will be emitted when content has been fetched.
+     *
+     * \since QGIS 3.2
+     */
+    void fetchContent( const QNetworkRequest &request );
+
     /**
      * Returns a reference to the network reply
      * \returns QNetworkReply for fetched URL content

tests/src/python/test_qgsnetworkcontentfetcher.py

@@ -22,7 +22,7 @@
 from qgis.core import QgsNetworkContentFetcher
 from utilities import unitTestDataPath
 from qgis.PyQt.QtCore import QUrl
-from qgis.PyQt.QtNetwork import QNetworkReply
+from qgis.PyQt.QtNetwork import QNetworkReply, QNetworkRequest
 import socketserver
 import threading
 import http.server
@@ -90,6 +90,21 @@ def testFetchUrlContent(self):
         html = fetcher.contentAsString()
         assert 'QGIS' in html
 
+    def testFetchRequestContent(self):
+        fetcher = QgsNetworkContentFetcher()
+        self.loaded = False
+        request = QNetworkRequest(QUrl('http://localhost:' + str(TestQgsNetworkContentFetcher.port) + '/qgis_local_server/index.html'))
+        fetcher.fetchContent(request)
+        fetcher.finished.connect(self.contentLoaded)
+        while not self.loaded:
+            app.processEvents()
+
+        r = fetcher.reply()
+        assert r.error() == QNetworkReply.NoError, r.error()
+
+        html = fetcher.contentAsString()
+        assert 'QGIS' in html
+
     def testDoubleFetch(self):
         fetcher = QgsNetworkContentFetcher()
         self.loaded = False