Fix 'PlantUMLHTTPError' object has no attribute 'message'

[jean]

Also, pass 'message' to super, so that it's displayed.
(I suspect this has to do with Python 3 changes?)

[jean]

@dougn good thing you didn't notice this PR yet 😬
It had a bug. Should be better now.

[yuriikonovaliuk]

@jean It seems that the new version also has a potential issue. The message is generated regardless of whether there is one already. In case if there is one it will be ignored and the generated one will be passed into the supers __init__.

[anb0s]

I'm facing this errror via mkdocs if there are some syntax issues in the plantuml block. Is the PR somehow blocked?

[wonderchang]

I'm facing this errror via mkdocs if there are some syntax issues in the plantuml block. Is the PR somehow blocked?

+1

[fuhrmanator]

I'm trying to use PlantUML in colab.research.google.com and can't get error handling to work properly because of this. Hoping you can merge this.

[sharif509]

At times it appears if the input UML Code has syntax errors. Please double-check the input UML Code. @jean @wonderchang @fuhrmanator

[fuhrmanator]

@Shareef509 if you could see the rendered image (that's returned despite the syntax error) you could see exactly what the error in the plantuml syntax and fix it. "Double checking" is hard if you can't get the error information.

[sharif509]

I had the same experience, that's why shared if it helps anyone else. Thank you.