Allow usage of a custom axios instance

[Or-Zarchi-Forter]

This PR solves #942, and any issues requesting specific advanced axios features (e.g. #1428, part of #1084)

Currently, it is impossible to add any interceptors to axios without modifying the global axios instance, which can effect other parts of your program in unwanted ways.

Also, hiding away the actual usage of the axios library in the request file means this generator will always play catch up with new axios features, or people asking for very specific axios parameters to be externalized.

This PR allows passing in a custom axios instance to the inner request module, providing an escape hatch for advanced users.

[blipk]

There's already docs and instructions for something like this: https://github.com/ferdikoomen/openapi-typescript-codegen/blob/master/docs/custom-request-file.md

Looks like the dev has possibly abandoned this repo though, there are breaking bugs that havent had attention in months.

[rchl]

There's already docs and instructions for something like this: master/docs/custom-request-file.md

Having to re-implement whole request logic means that there is a very high chance of things breaking on new version of this package being released.

This change looks like it would be a lot less prone to that.

Although ideally there would be some axios-client-specific method that one could override like createAxiosInstance so that it would be even more future proof but I imagine that would need more refactoring and potentially more axios-client-specific logic.

[Or-Zarchi-Forter]

There's already docs and instructions for something like this: master/docs/custom-request-file.md

I've mentioned this method in the docs i've added. But as @rchl mentioned, that process is very error-prone, and when attempting it I ended up copying hundreds of lines of code from the default generated version of request.ts

[yehonatanz]

Would really love to this merged as well.
My use case has a very carefully configured axios client going through a application-level proxy (not a standard HTTP proxy).
The complexity of copying all the code from the default request.ts file made me give up and opt for a different openapi client generator instead.
It would be really nice if this got merged and I could re-consolidate my openapi clients.

[blipk]

@yehonatanz
Which API generator did you go with instead?
Curious as this hasn't had any updates in a while

[yehonatanz]

@yehonatanz Which API generator did you go with instead? Curious as this hasn't had any updates in a while

@blipk this one with the typescript-axios generator selected.
Pretty versatile, but has the distinct disadvantage of being written in Java and requiring a JRE to run (also I find it generates a more awkward interface, but that's a matter of taste I guess)

[esbenam]

Would love to see this merged - as others have already mentioned, this is a blocker for some people using customised axios instances. Anything we can do to help this along? Is this implementation considered a viable option, or do the maintainers have a different view of how this should be implemented/handled?

Copying and overriding the request file won't do the trick in my case, since I am generating a client used by multiple projects, each of them having the need to pass in a custom axios instance when they generate the client (setting default custom headers etc.)

[thegris]

I am also looking for this functionality, thank you!

[Or-Zarchi-Forter]

@ferdikoomen any chance this can be merged in? it's a relatively simple change, and it seems like it addresses a common pain point

[atomicleopard]

Would be awesome to see some movement on this, such a small change but such a big impact 🙏

[Or-Zarchi-Forter]

thank you @ferdikoomen for merging this PR 🎈

[jm-bairesdev]

Does this work for non-named clients too (--name is not used), where all we have is static public functions in our generated services/clients?
We don't instantiate the client, so we don't have a way to:

const client = new GeneratedClient({ BASE: 'http://localhost:8123' }, AxiosHttpRequestWithRetry)

[shervinw]

@ferdikoomen ref #942 I don't think that this implementation solves all cases when needing to provide a custom axios instance, since the axios instance instantiation can only occur inside the BaseHttpRequest override, it results in a too tightly coupled solution.

The axios instance would be better provided as an injected dependency in the constructor, so that we can create and pass in the instance from anywhere.

I am forking this repo to solve the problem, with backward compatibility, I'll create a PR and would be great if it could be considered to merge