Streamed response gets buffered and returned in one chunk

[danharrin]

Octane Version

2.3.12

Laravel Version

11.9.2

PHP Version

8.3.0

What server type are you using?

Roadrunner

Server Version

2024.1.2

Database Driver & Version

No response

Description

When streaming a response from a route behind Octane, the response gets buffered and arrives all at once instead of as it is generated.

Currently, wire:stream in Livewire is completely broken when using Laravel Octane, but the issue is not specific to Livewire and my instructions below use native Laravel and vanilla JavaScript only.

Steps To Reproduce

I have created a minimal reproduction repository. Follow the instructions in the README to observe the behaviour of artisan serve as opposed to Octane. There is a small amount of JavaScript in welcome.blade.php that sends the request and outputs the chunks in real time.

Here is the response, note the sleep(1) calls to simulate an artificial delay in receiving the stream chunks. When using artisan serve, there is a second delay between each number appearing. When using Octane, there is a 5 second delay before all numbers appear at once.

return response()->stream(function () {
    echo 1;

    ob_flush();
    flush();
    sleep(1);

    echo 2;

    ob_flush();
    flush();
    sleep(1);

    echo 3;

    ob_flush();
    flush();
    sleep(1);

    echo 4;

    ob_flush();
    flush();
    sleep(1);

    echo 5;
}, 200, [
    'Content-Type' => 'text/html; charset=utf-8;',
    'Cache-Control' => 'no-cache',
    'X-Accel-Buffering' => 'no',
]);

[gazzoy]

@barryvdh do you happen to have any insights on this?

Thought you might have any ideas as just found you previously solved StreamedResponse stuff in #151.

[barryvdh]

Yeah well the 'fix' was to wait until the stream was finished. At that time I didn't find a way to pass the actual stream.

[gazzoy]

@barryvdh Thanks you! Ok, so seems like streaming w/ Octane is the darkside of the force...

[github-actions[bot]]

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[donnysim]

RoadRunner does not seem to work well with buffers and uses Generators. Maybe Octane could support Generators?

return response()->stream(function (): Generator {
        yield '1';
        sleep(1);
        yield '2';
        sleep(1);
        yield '3';
    }, 200, [
        'Content-Type' => 'text/html; charset=utf-8;',
        'Cache-Control' => 'no-cache',
        'X-Accel-Buffering' => 'no',
    ]);

RoadRunnerClient:

/**
     * Send the response to the server.
     */
    public function respond(RequestContext $context, OctaneResponse $octaneResponse): void
    {
        if ($octaneResponse->outputBuffer &&
            ! $octaneResponse->response instanceof StreamedResponse &&
            ! $octaneResponse->response instanceof BinaryFileResponse) {
            $octaneResponse->response->setContent(
                $octaneResponse->outputBuffer.$octaneResponse->response->getContent()
            );
        }

        if ($octaneResponse->response instanceof StreamedResponse) {
            $this->client->getHttpWorker()->respond(
                $octaneResponse->response->getStatusCode(),
                $octaneResponse->response->getCallback()(), // Passing here the Generator
                $this->toPsr7Response($octaneResponse->response)->getHeaders()
            );
        } else {
            $this->client->respond($this->toPsr7Response($octaneResponse->response));
        }
    }

this works with RoadRunner.

[Orrison]

RoadRunner does not seem to work well with buffers and uses Generators. Maybe Octane could support Generators?

return response()->stream(function (): Generator {
        yield '1';
        sleep(1);
        yield '2';
        sleep(1);
        yield '3';
    }, 200, [
        'Content-Type' => 'text/html; charset=utf-8;',
        'Cache-Control' => 'no-cache',
        'X-Accel-Buffering' => 'no',
    ]);

RoadRunnerClient:

/**
     * Send the response to the server.
     */
    public function respond(RequestContext $context, OctaneResponse $octaneResponse): void
    {
        if ($octaneResponse->outputBuffer &&
            ! $octaneResponse->response instanceof StreamedResponse &&
            ! $octaneResponse->response instanceof BinaryFileResponse) {
            $octaneResponse->response->setContent(
                $octaneResponse->outputBuffer.$octaneResponse->response->getContent()
            );
        }

        if ($octaneResponse->response instanceof StreamedResponse) {
            $this->client->getHttpWorker()->respond(
                $octaneResponse->response->getStatusCode(),
                $octaneResponse->response->getCallback()(), // Passing here the Generator
                $this->toPsr7Response($octaneResponse->response)->getHeaders()
            );
        } else {
            $this->client->respond($this->toPsr7Response($octaneResponse->response));
        }
    }

this works with RoadRunner.

@donnysim I am just curious. Is what you posted here a complete fix for getting Streamed Responses to work in Octane RoadRunner? Or does more change need to be done to support Generators fully as you suggest?

[donnysim]

@Orrison technically would still need to check if it's a generator for edge cases but it's all you need for it to work with RoadRunner as it already accepts a Generator|string.

[Orrison]

@Orrison technically would still need to check if it's a generator for edge cases but it's all you need for it to work with RoadRunner as it already accepts a Generator|string.

That's amazing. Do you plan on opening a PR for this into Octane?

Would you like any assistance in doing so or help testing?

[Orrison]

@crynobone would y'all consider @donnysim's suggestion of using Generators here?

[donnysim]

I believe @danharrin wanted a stab at a PR as I'm not too time-free to invest time into PR's at the moment. If he decides otherwise then anyone is free maybe to attempt one, or I might as the week or next goes if freed up more. On the side note, when inspecting this I was thinking if it would be possible to convert the buffer into a Generator while maybe catching PHP_OUTPUT_HANDLER_START and PHP_OUTPUT_HANDLER_FINAL etc., but all the clients differ wildly in how they work that there's really no way I'd have time to analyze them all to find if that's a plausible approach.

[Orrison]

I believe @danharrin wanted a stab at a PR as I'm not too time-free to invest time into PR's at the moment. If he decides otherwise then anyone is free maybe to attempt one, or I might as the week or next goes if freed up more. On the side note, when inspecting this I was thinking if it would be possible to convert the buffer into a Generator while maybe catching PHP_OUTPUT_HANDLER_START and PHP_OUTPUT_HANDLER_FINAL etc., but all the clients differ wildly in how they work that there's really no way I'd have time to analyze them all to find if that's a plausible approach.

No problem at all! I totally understand. I just wanted to check with you if you had already planned on doing so. But since you are busy I can see if we and/or @danharrin can take a crack at it. I wanted to thank you for your research and work on this! If we can get StreamedResponses to work in Octane it would fill a massive gap in Octane right now.

[driesvints]

Was anyone still working on a PR for this?

[Orrison]

@driesvints Yes, we believe we have found a fix for this. We overrode the Octane classes in our project as we needed the fix as quickly as possible.

https://github.com/canyongbs/advisingapp/pull/823

We can open a PR to Octane soon with the change.