Render roi thumbnail fixes

[will-moore]

Found bug in render_roi_thumbnail as part of the iviewer work at ome/omero-iviewer#311
We don't use render_roi_thumbnail in any of our clients (old webgateway viewer uses Shapes thumbnails, not ROIs).

Added tests at ome/openmicroscopy#6235

To test:

• For an ROI with a single shape where Z & T are not set, try /webgateway/render_roi_thumbnail/{ROI_ID}/

[pwalczysko]

Tested 4 cases

• set Z and T on ROI https://merge-ci.openmicroscopy.org/web/webgateway/render_roi_thumbnail/95464/

• set Z and do not set T https://merge-ci.openmicroscopy.org/web/webgateway/render_roi_thumbnail/95463/

• do not set Z and set T https://merge-ci.openmicroscopy.org/web/webgateway/render_roi_thumbnail/95465/

• do not set Z and do not set T https://merge-ci.openmicroscopy.org/web/webgateway/render_roi_thumbnail/95462/

See links , user-3

All works as expected, I am getting insets such as in the screenshot below.

Ready to merge fmpov.

[joshmoore]

Sorry, @will-moore. Can you describe in words what the change in behavior is?

[will-moore]

Previously I got an exception if theT was None:

File "/Users/wmoore/Desktop/WEB/omero-web/omeroweb/webgateway/views.py" in render_roi_thumbnail
  436.             if t < minT:

Exception Type: TypeError at /webgateway/render_roi_thumbnail/175180
Exception Value: '<' not supported between instances of 'NoneType' and 'NoneType'

[joshmoore]

Understood and thanks. Like the public user fix, would be good to see this rolled into a release soon. Only possible follow-up thought is if there's would be any chance in our test suite to add a check for this.

[will-moore]

Added tests at ome/openmicroscopy#6235

[jburel]

Few more BytesIO in the method that are not closed e.g.

omero-web/omeroweb/webgateway/views.py

Line 599 in e2fc30c

rv = BytesIO()

omero-web/omeroweb/webgateway/views.py

Line 632 in e2fc30c

img = Image.open(BytesIO(jpeg_data))

and few others in render_image, render_shape_masks. The one in the last 2 methods could be fixed in a follow-up PR if you prefer.

[will-moore]

I would prefer not to add more to this PR.
Already this and ome/openmicroscopy#6235 have grown from the original bug fix (which isn't needed now for ome/omero-iviewer#311) so it would be good to get them merged.

[jburel]

Could you create an issue so we review the resources opened in a follow-up PR?

[will-moore]

Created #175

[will-moore]

Tests failing at https://merge-ci.openmicroscopy.org/jenkins/job/OMERO-test-integration/427/testReport/junit/OmeroWeb.test.integration.test_thumbnails/TestRoiThumbnails/test_roi_thumbnail_0_1_/

midZ = zList[len(zList)/2]
E       TypeError: list indices must be integers or slices, not float

because this PR is NOT merged and ome/openmicroscopy#6235 is merged.

[joshmoore]

Retriggered the integration tests now that the commit is green.

[joshmoore]

https://merge-ci.openmicroscopy.org/jenkins/job/OMERO-test-integration/428/testReport/OmeroWeb.test.integration.test_thumbnails/ is now green. 👍