Introduce changes necessary for Dart 3.0.0/Flutter 3.10.0

[noordawod]

Recent versions of the Dart SDK have tightened the rules for which objects can be sent across isolates (see https://api.dart.dev/stable/3.0.0/dart-isolate/SendPort/send.html and dart-lang/sdk@67683c39).

Bottom line: It's not possible to send an arbitrary class instance across isolates anymore, this may cause a crash when deserializeAsync is called from an isolate different from the isolate used to call the API operation: flutter/flutter#126520

This pr introduces the following changes:

1. Add a new function decodeAsync to decode a JSON, suitable to be called from an isolate.
2. Expose ApiClient._deserialize (as ApiClient.fromJson) so that users can call it after decoding the JSON on an isolate.

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  ./bin/utils/export_docs_generators.sh
  

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@jaumard (2018/09) @josh-burton (2019/12) @amondnet (2019/12) @sbu-WBT (2020/12) @kuhnroyal (2020/12) @agilob (2020/12) @ahmednfwela (2021/08)

[ahmednfwela]

Can this wait until #14346 and #15485 land ?

because after these 2 PRs we will have an infrastructure to test this code similar to this https://github.com/OpenAPITools/openapi-generator/tree/master/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake_tests

[noordawod]

For sure, @ahmednfwela. Got an eta?

[ahmednfwela]

it's currently blocked by #10189 waiting for a fix soon

[konnic]

@noordawod thanks for opening the PR!

After upgrading to Flutter 3.10.1 I discovered that I'm blocked by the dart2 generator, because my generated Dart API client pub depends on intl: "^0.17.0", while the Flutter SDK now depends on intl: "0.18.0". So if I'm not mistaken this should be adjusted in the pubspec.mustache:19 file?

This was also reported in this issue: #15510

When running flutter pub get this is my output:

Resolving dependencies...
Because myapp depends on core_api from path which depends on intl ^0.17.0, intl ^0.17.0 is required.
So, because myapp depends on intl ^0.18.0, version solving failed.
exit code 1

[noordawod]

@noordawod thanks for opening the PR!

After upgrading to Flutter 3.10.1 I discovered that I'm blocked by the dart2 generator, because my generated Dart API client pub depends on intl: "^0.17.0", while the Flutter SDK now depends on intl: "0.18.0". So if I'm not mistaken this should be adjusted in the pubspec.mustache:19 file?

This was also reported in this issue: #15510

When running flutter pub get this is my output:

Resolving dependencies...
Because myapp depends on core_api from path which depends on intl ^0.17.0, intl ^0.17.0 is required.
So, because myapp depends on intl ^0.18.0, version solving failed.
exit code 1

You could override the dependency and enforce a specific version, I do it:

dependency_overrides:
  intl: "^0.18.0"

More info: https://rdr.to/Cwq7C2il78u

UPDATE: I modified this pr and patched the pubspec Mustache template file, hopefully we'll be able to merge this pr once the prerequisites are merged.

[noordawod]

Can this wait until #14346 and #15485 land ?

because after these 2 PRs we will have an infrastructure to test this code similar to this https://github.com/OpenAPITools/openapi-generator/tree/master/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake_tests

What do you think about doing it the other way around? Merging this first and then the other 2 pr's? Seems to me that the latter two might take a while...

[ahmednfwela]

yes we can do that but,can you create a separate issue to track the needed tests?

[noordawod]

yes we can do that but,can you create a separate issue to track the needed tests?

I need help with that :| I never wrote tests… Would you like to help?

[ahmednfwela]

it's ok after the new PR I will write the tests

[noordawod]

it's ok after the new PR I will write the tests

Perfect, thank you! Then, this pr is updated with upstream and ready to merge.

[ahmednfwela]

cc @wing328 Ready for merge
also friendly reminder that #10189 is blocking multiple PRs :)

[noordawod]

Bump :)