[typescript-angular] Support blob response types

[oaklandcorp-jkaiser]

Fixes #11021

Generated service methods will try to decide its response type by pattern matching the accept header for text, then json, otherwise defaults to a blob.

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[amakhrov]

Thanks for your PR!
The fix looks good, as it fixes the runtime behavior.

It looks like the type signature of the api service method remains incorrect in this case - in your example it stays Observable<string> instead of Observable<Blob>

I realize that a proper fix for the typings can be more involved (just look at those gazillions overloads in Angular's own HttpClient#request). So we can probably address it later - unless you feel like doing it and have a good approach for that in mind. Any thoughts?

[oaklandcorp-jkaiser]

Thanks for your PR! The fix looks good, as it fixes the runtime behavior.

It looks like the type signature of the api service method remains incorrect in this case - in your example it stays Observable<string> instead of Observable<Blob>

I realize that a proper fix for the typings can be more involved (just look at those gazillions overloads in Angular's own HttpClient#request). So we can probably address it later - unless you feel like doing it and have a good approach for that in mind. Any thoughts?

Yes, I noticed that as well when throwing together this quick fix. I decided to keep things minimal so things would be easier to review. Also I believe that same issue plagues the support of a text response type as well, so I went into this thinking the fix wasn't introducing that as a new problem. I would love to have a solution that had an accurate TypeScript interface, but I don't think I'm familiar enough with the project yet to envision how I would make it happen. So I'd lean towards incremental improvement unless someone more experienced has a proposed solution they could walk me through.

[oaklandcorp-jkaiser]

I believe I've addressed all PR feedback so far. If there are any other changes you all would suggest please let me know and I'll try to address them as well!

[djnalluri]

@macjohnny, does this need a milestone?

[macjohnny]

@djnalluri it will automatically be part of the next release. Added milestone 5.4.0 for reference