Subscription Support

[maaft]

Hi!

What would be the required steps to add subscription support to this client?

[maaft]

@Yamashou I got it working by using a slightly modified websocket client from hasura: https://gist.github.com/maaft/ac197c72fe5d18eec5916f3f5a75943f

How to use with generated structs (generated.SubscribeProjectsQuery, generated.SubscribeProjects):

func main() {
	subscriptionClient := subscription.NewSubscriptionClient("ws://localhost:8080/graphql")

	defer subscriptionClient.Close()

	errChan := make(chan error)

	subscriptionID, err := subscriptionClient.Subscribe(generated.SubscribeProjectsQuery, nil, func(dataValue *json.RawMessage, errValue error) error {
		if errValue != nil {
			errChan <- errValue
		}

		data := generated.SubscribeProjects{}
		if err := graphqljson.UnmarshalData(*dataValue, &data); err != nil {
			errChan <- err
		}

		for _, p := range data.QueryProject {
			fmt.Println(p.Name)
		}

		return nil
	})

	if err != nil {
		panic(err)
	}

	go func() {
		err := <-errChan
		if err != nil {
			subscriptionClient.Unsubscribe(subscriptionID)
			panic(err)
		}
	}()

	err = subscriptionClient.Run()

	if err != nil {
		panic(err)
	}
}

Do you think you could integrated this properly into this project? I think it should be relatively easy.

[Yamashou]

Thanks for issue and a script. Show me your implementation and think about it

[Yamashou]

[Q] nhooyr.io/websocket is that you guess best ws client ?

If you compared other clients, tell me result

[Yamashou]

If you have time, I want you to create PR for this issues.
my start point is reading your gist. So, It takes longer to implement this client than you do

[maaft]

Hi! I also just copy-pasted the client I found and it works fine so far. The only issue is 100% CPU after some time, but that should be fixable.
I see if I can spend some time on this on the upcoming year.

[maaft]

Just to document it for later:
The >100% CPU issue is related to this function here:

func (wh *websocketHandler) ReadJSON(v interface{}) error {
	ctx, cancel := context.WithTimeout(wh.ctx, wh.timeout)
	defer cancel()
	return wsjson.Read(ctx, wh.Conn, v)
}

The timeout is set to 1 minute, so when for 1 minute no messages arrive, the load starts. When I use it like this:

func (wh *websocketHandler) ReadJSON(v interface{}) error {
	return wsjson.Read(wh.ctx, wh.Conn, v)
}

the issue is gone. I'm not sure about the implications though. But for now it works for me.

[Yamashou]

Thanks for comment and response !
I try to create new client package for cache and interceptor now. If I finished it when you create PR for subscription support, I start this issue.

[delaneyj]

@Yamashou I got it working by using a slightly modified websocket client from hasura: https://gist.github.com/maaft/ac197c72fe5d18eec5916f3f5a75943f

How to use with generated structs (generated.SubscribeProjectsQuery, generated.SubscribeProjects):

func main() {
	subscriptionClient := subscription.NewSubscriptionClient("ws://localhost:8080/graphql")

	defer subscriptionClient.Close()

	errChan := make(chan error)

	subscriptionID, err := subscriptionClient.Subscribe(generated.SubscribeProjectsQuery, nil, func(dataValue *json.RawMessage, errValue error) error {
		if errValue != nil {
			errChan <- errValue
		}

		data := generated.SubscribeProjects{}
		if err := graphqljson.UnmarshalData(*dataValue, &data); err != nil {
			errChan <- err
		}

		for _, p := range data.QueryProject {
			fmt.Println(p.Name)
		}

		return nil
	})

	if err != nil {
		panic(err)
	}

	go func() {
		err := <-errChan
		if err != nil {
			subscriptionClient.Unsubscribe(subscriptionID)
			panic(err)
		}
	}()

	err = subscriptionClient.Run()

	if err != nil {
		panic(err)
	}
}

Do you think you could integrated this properly into this project? I think it should be relatively easy.

If I try to run gqlgenc on gql files that contains a subscription I get

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x40 pc=0x8a86a0]

goroutine 1 [running]:
github.com/Yamashou/gqlgenc/clientgen.(*SourceGenerator).NewResponseField(0xc000375d98, 0xa51d80, 0xc00067ca80, 0xc0002ca6b8)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/clientgen/source_generator.go:147 +0x480
github.com/Yamashou/gqlgenc/clientgen.(*SourceGenerator).NewResponseFields(0xc000375d98, 0xc0007abe00, 0x1, 0x1, 0x30, 0x7fd726ebcd28, 0x30)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/clientgen/source_generator.go:83 +0xc5
github.com/Yamashou/gqlgenc/clientgen.(*SourceGenerator).NewResponseField(0xc000375d98, 0xa51d80, 0xc00067ca00, 0xc0002ca6b0)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/clientgen/source_generator.go:142 +0xa5
github.com/Yamashou/gqlgenc/clientgen.(*SourceGenerator).NewResponseFields(0xc000375d98, 0xc0007abe10, 0x1, 0x1, 0x0, 0xd2cec0, 0xc000375b48)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/clientgen/source_generator.go:83 +0xc5
github.com/Yamashou/gqlgenc/clientgen.(*Source).OperationResponses(0xc000375d78, 0xd2cec0, 0x0, 0x0, 0x0, 0x0)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/clientgen/source.go:144 +0x125
github.com/Yamashou/gqlgenc/clientgen.(*Plugin).MutateConfig(0xc0000aab80, 0xc00018cf20, 0xc0000aab80, 0x7fd6fc6bbed8)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/clientgen/client.go:69 +0x67c
github.com/Yamashou/gqlgenc/generator.Generate(0xa582d0, 0xc0000260d0, 0xc0000de6c0, 0xc00018bf60, 0x1, 0x1, 0xc000084710, 0x4426ca)
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/generator/generater.go:32 +0x2e2
main.main()
        /home/delaney/.gvm/pkgsets/go1.16.2/global/pkg/mod/github.com/!yamashou/gqlgenc@v0.0.0-20210330020310-5eab2091f840/main.go:30 +0x1cc

I'd like to try this way of supporting subscriptions but no luck on the initial type generation. What am I doing wrong?

[raphaelfff]

Facing the same issue, we ended up creating our own GQL client: https://github.com/infiotinc/gqlgenc

[maaft]

Thank you, looks good!

I'd advice you to honor the work of @Yamashou in your repository though as you obviously based your work on his. Currently you are violating the MIT License of this repo.

[raphaelfff]

Thank you :)
The relevant directories that are direct copies (or at least started this way) from this repo contain the LICENSE file from Yamashou, and some files that have been modified contain a link to their origin. But i agree that adding an Acknowledgement section in the readme would only be fair!