Add download button on the popup modal during model export

Opening a new window tab inside an AJAX request turned out
to be almost impossible without using some non-reliable hacks.
Hence providing a button on the popup modal for user to click.

client/src/components/FocusedCrawling.js

@@ -329,8 +329,8 @@ class FocusedCrawling extends Component {
        function(model_file) {
          var url = model_file;
          var message = (url.indexOf("_model.zip")==-1)?"Model was not created.":"Model created successfully.";
-         if(url.indexOf("_model.zip")>-1) window.open(url,'Download');
-         this.setState({loadingModel:false, disabledCreateModel:false, createModelMessage:message, openMessageModelResult:true,})
+
+         this.setState({modelDownloadURL: model_file, loadingModel:false, disabledCreateModel:false, createModelMessage:message, openMessageModelResult:true})
          this.forceUpdate();
        }.bind(this)
      );
@@ -340,6 +340,11 @@ class FocusedCrawling extends Component {
     this.getCreatedModel(this.state.session);
   }
 
+  downloadExportedModel = (event) => {
+    if((this.state.modelDownloadURL || "").indexOf("_model.zip") !== -1)
+      window.open(this.state.modelDownloadURL, 'download')
+  }
+
   handleCloseModelResult = () => {
     this.setState({openMessageModelResult: false});
   };
@@ -552,6 +557,12 @@ class FocusedCrawling extends Component {
               onRequestClose={this.handleCloseModelResult.bind(this)}
             >
               {this.state.createModelMessage}
+              <RaisedButton
+                label="Download"
+                style={{margin: 5}}
+                labelStyle={{textTransform: "capitalize"}}
+                onClick={this.downloadExportedModel}
+              />
             </Dialog>
             </div>
          </CardText>