Fixed an issue where the downloaded ERD diagram was 0 bytes. Fixes #7187

docs/en_US/release_notes.rst

@@ -11,6 +11,7 @@ notes for it.
 .. toctree::
    :maxdepth: 1
 
+   release_notes_6_9
    release_notes_6_8
    release_notes_6_7
    release_notes_6_6

docs/en_US/release_notes_6_9.rst

@@ -0,0 +1,20 @@
+************
+Version 6.9
+************
+
+Release date: 2022-05-05
+
+This release contains a number of bug fixes and new features since the release of pgAdmin4 6.8.
+
+New features
+************
+
+
+Housekeeping
+************
+
+
+Bug fixes
+*********
+
+ | `Issue #7187 <https://redmine.postgresql.org/issues/7187>`_ -  Fixed an issue where the downloaded ERD diagram was 0 bytes.

web/pgadmin/tools/erd/static/js/erd_tool/ui_components/BodyWidget.jsx

@@ -657,11 +657,24 @@ export default class BodyWidget extends React.Component {
     };
 
     setTimeout(()=>{
+      let width = this.canvasEle.scrollWidth + 10;
+      let height = this.canvasEle.scrollHeight + 10;
+      let isCut = false;
+      /* Canvas limitation - https://html2canvas.hertzen.com/faq */
+      if(width >= 32767){
+        width = 32766;
+        isCut = true;
+      }
+      if(height >= 32767){
+        height = 32766;
+        isCut = true;
+      }
       html2canvas(this.canvasEle, {
-        width: this.canvasEle.scrollWidth + 10,
-        height: this.canvasEle.scrollHeight + 10,
+        width: width,
+        height: height,
         scrollX: 0,
         scrollY: 0,
+        scale: 1,
         useCORS: true,
         allowTaint: true,
         backgroundColor: window.getComputedStyle(this.canvasEle).backgroundColor,
@@ -691,6 +704,10 @@ export default class BodyWidget extends React.Component {
           ele.style.transform = prevTransform;
         });
         this.setLoading(null);
+        if(isCut) {
+          Notify.alert(gettext('Maximum image size limit'),
+            gettext('The downloaded image has exceeded the maximum size of 32767 x 32767 pixels, and has been cropped to that size.'));
+        }
       });
     }, 1000);
   }