ReactPHP Client - Server error testing and reactive approach based on server response - in a streamed promised response

[gidzr]

Hi All

i'm using this:

  $stream = React\Promise\Stream\unwrapReadable(
     $this->httpClient
     ->then(
        function (Psr\Http\Message\ResponseInterface $response) {

to get the streamed results of a server.

But if there's an issue like ports blocked, IP blocked, or server down, I want to be able to test for and respond to this based on the timeout I receive in the function Exception

        function (Exception $e) {

BUT i can't currently do this because its all in a promise and doesn't get sorted until the promise is resolved on an await.

await(first($stream, 'data')))

is it possible to test the connection when setting it up with

  $this->connector = new React\Socket\Connector(array(

without having to execute / resolve the promise it relates to?

To clarify, I know how to catch errors within the response, and how to catch errors with $stream->on('error',()=>{}). But once the errors are caught this far down the process, the promise is already resolving, and it's not really possible to intercept with a validation / error approach, like trying to restart the server or changing to different port and then recursively kicking off the client request a second time.

ie. All the existing error catching, relies on the promise resolving, so none of it is triggered until after the promise is in play, which makes it impossible to 'intercept' and unpack while in flight.

Any ideas?

Cheers

[gidzr]

Hi @clue

Just to make it a bit clearer what I'm attempting.. and why it's been a bit of an issue:

1. I run a client call to server with reactPHP connector + browser using streaming interface.
2. I receive an error due to the server being down, blocked port, or blocked IP (unknown error at this point)
3. In the stream response, on-error, I run some checks to see what might be the issue, and based on results of my ping to server, have determined the remote computer running and live (no error on port 80), port 1000 for the server isn't responding which I conclude is a 'server app down' issue.
4. I run the 'restart_remote_server' function .. which is successful.. causing the remote server to listen on port 1000 and ready to accept client calls.
5. I re-run the entire reactPHP client sequence to a) create a new connection, b) create new browser with ssl certs etc and body data, c) and re-run the streaming response interface per the basic standard example you show here: https://reactphp.org/promise-stream/#unwrapreadable

However, the existing stream is still technically running therefore all the code is run when the promise being called.. at the very end of the code using: await(first($stream, 'data')), and it seems it's not technically possible to call or change the direction of the promise from within the promise and dynamically modifying itself or stopping itself midway to re-kickoff the entire process again after having restarted the server.

This is where promises do my head in a bit. At first I though I could simply 'escape' the function on this error and kick off the steps again. But seems this is not possible from within the promise - it's all packed like a suitcase.

*** I suspect maybe I need to try-catch the server errors at the point of calling the promise - on the await(first($stream, 'data')).. but i hope not - it's a bit hacky. ***

I get this error:
Warning: Cannot modify header information - headers already sent by (output started at
An uncaught Exception was encountered
Type: RuntimeException

Message: An error occured on the underlying stream while waiting for event: Not a readable stream

Filename: C:\xampp81\php\vendor\react\promise-stream\src\functions.php

Line Number: 152

Backtrace:

File: C:\xampp81\php\vendor\evenement\evenement\src\EventEmitterTrait.php
Line: 143
Function: React\Promise\Stream{closure}

File: C:\xampp81\php\vendor\react\promise-stream\src\UnwrapReadableStream.php
Line: 81
Function: emit

File: C:\xampp81\php\vendor\react\promise\src\Internal\RejectedPromise.php
Line: 73
Function: React\Promise\Stream{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 173
Function: then

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 221
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 192
Function: settle

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 292
Function: reject

File: C:\xampp81\php\vendor\react\promise\src\Internal\RejectedPromise.php
Line: 73
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 180
Function: then

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 221
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 286
Function: settle

File: C:\xampp81\php\vendor\react\promise\src\Internal\FulfilledPromise.php
Line: 47
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 180
Function: then

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 221
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 192
Function: settle

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 292
Function: reject

File: C:\xampp81\php\vendor\react\promise\src\Deferred.php
Line: 50
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\http\src\Io\Transaction.php
Line: 98
Function: reject

File: C:\xampp81\php\vendor\react\promise\src\Internal\RejectedPromise.php
Line: 73
Function: React\Http\Io{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 173
Function: then

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 221
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 192
Function: settle

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 292
Function: reject

File: C:\xampp81\php\vendor\react\promise\src\Internal\RejectedPromise.php
Line: 73
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 180
Function: then

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 221
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 192
Function: settle

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 292
Function: reject

File: C:\xampp81\php\vendor\react\promise\src\Deferred.php
Line: 50
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\http\src\Io\Sender.php
Line: 115
Function: reject

File: C:\xampp81\php\vendor\evenement\evenement\src\EventEmitterTrait.php
Line: 143
Function: React\Http\Io{closure}

File: C:\xampp81\php\vendor\react\http\src\Io\ClientRequestStream.php
Line: 243
Function: emit

File: C:\xampp81\php\vendor\react\promise\src\Internal\RejectedPromise.php
Line: 73
Function: closeError

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 173
Function: then

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 221
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 192
Function: settle

File: C:\xampp81\php\vendor\react\promise\src\Promise.php
Line: 292
Function: reject

File: C:\xampp81\php\vendor\react\socket\src\TimeoutConnector.php
Line: 53
Function: React\Promise{closure}

File: C:\xampp81\php\vendor\react\event-loop\src\Timer\Timers.php
Line: 101
Function: React\Socket{closure}

File: C:\xampp81\php\vendor\react\event-loop\src\StreamSelectLoop.php
Line: 185
Function: tick

File: C:\xampp81\php\vendor\react\event-loop\src\Loop.php
Line: 250
Function: run

File: C:\xampp81\php\vendor\react\async\src\SimpleFiber.php
Line: 61
Function: run

File: C:\xampp81\php\vendor\react\async\src\SimpleFiber.php
Line: 71
Function: start

File: C:\xampp81\php\vendor\react\async\src\functions.php
Line: 357
Function: suspend

File: C:\xampp81\htdocs\villg.life\application\helpers\sockethttpclientservers_helper.php
Line: 1772
Function: React\Async\await

File: C:\xampp81\htdocs\villg.life\application\controllers\lead\LocalServerController.php
Line: 62
Function: run

[gidzr]

Solved..

I have to run the checks using a try-catch on the promise resolve / await..

which means I need to throw an exception from the validation tests inside the stream function,

I've got it working - but not the prettiest approach.

Cheers