Bug #92985 Add ability to export an unselected Diagram to PNG/[other] from Python script
Submitted: 29 Oct 2018 9:47 Modified: 5 Dec 2018 22:53
Reporter: Sergey Susikov Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Workbench: Modeling Severity:S4 (Feature request)
Version:6.3.10 OS:Any
Assigned to: CPU Architecture:Any
Tags: WBBugReporter

[29 Oct 2018 9:47] Sergey Susikov
Description:
Preface:
I'm trying to integrate MySQL Workbench diagram exporting to a CI pipeline and thus using a Docker image to run it in headless mode with X11 display. It means that the model file I open is "fresh" every time the program starts (i.e. no cache/preferences saved). Using built-in Python shell it's possible to export a diagram only if it's selected manually (by mouse click), there's no way to open a model and choose any (even if there's only one) diagram from the code.

How to repeat:
On a fresh installation run the following script (for instance, like this: `mysql-workbench --run 'grt.modules.Workbench.exportPNG('model.png')' --model ~/workspace/model.mwb --quit-when-done`):
```
import grt
grt.modules.Workbench.exportPNG('model.png')
```

The result is:
> Current diagram cannot be exported as image, please select a diagram first.

Expected result:
The diagram is saved as a PNG file.

Suggested fix:
There are several potential ways to resolve the issue:
1. Use `grt.modules.WbPrinting.printTo*File` approach - make methods that accept diagram and file name as arguments;
2. Make `grt.modules.Workbench.editObject` open diagram tab when call with Diagram object (now throws unsupported type exception);
3. Add a wrapper to "View -> Select next main tab" menu item as diagram tab actually opens on program load, just not being selected automatically;
4. Select first diagram automatically when loading the program.
[29 Oct 2018 9:55] Marcin Szalowicz
Thank you for the feature request.
[5 Dec 2018 22:53] Christine Cole
Posted by developer:
 
Fixed as of the upcoming MySQL Workbench 8.0.14 release, and here's the changelog entry:

The following new functions were added to the Workbench GRT module: 
* activateDiagram(<Diagram>) 
  Opens the selected EER diagram for use with the
  exportPNG, exportSVG, exportPS, and exportPDF functions. 

* exportDiagramToPng(<Diagram>, <Path>) 
  Performs a PNG export of an EER diagram to the path
  provided without activating it.

Thank you for the bug report.