[stream/ws_client] Reading long stdout is truncated at 32768 chars

[paramjeet01]

[stream/ws_client] Reading long stdout is truncated at 32768 chars

[roycaihw]

/help

It is unclear where the limitation is coming from. Whether the limitation is coming from this client or some underlying library

[k8s-ci-robot]

@roycaihw:
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In response to this:

/help

It is unclear where the limitation is coming from. Whether the limitation is coming from this client or some underlying library

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[paramjeet01]

I'm not sure where the data is lost in between but I'm trying this code as suggested by @Paul424 in this issue :
kubernetes-client/python-base#190. My understanding is that the data is lost while reading from the cat command,

def _extract_xcom(self, pod: V1Pod):
    try:
        self.log.info(f'Running command... cat {PodDefaults.XCOM_MOUNT_PATH}/return.json')

        # Can't use _preload_content=True because that would return str(json.load(response))
        client = kubernetes_stream(
            self._client.connect_get_namespaced_pod_exec,
            pod.metadata.name,
            pod.metadata.namespace,
            container=PodDefaults.SIDECAR_CONTAINER_NAME,
            command=[
                '/bin/sh',
                '-c',
                f'cat {PodDefaults.XCOM_MOUNT_PATH}/return.json',
            ],
            stderr=True,
            stdin=False,
            stdout=True,
            tty=False,
            _preload_content=False,
            _request_timeout=10,
        )
        client.run_forever(timeout=10)
        resp = client.read_all()
        self.log.info("Received {} ({}) ({} ... {}))".format(type(resp), len(resp), resp[:64], resp[-64:]))

        # validate it's valid json
        _ = json.loads(resp)

        # Terminate the sidecar
        _ = kubernetes_stream(
            self._client.connect_get_namespaced_pod_exec,
            pod.metadata.name,
            pod.metadata.namespace,
            container=PodDefaults.SIDECAR_CONTAINER_NAME,
            command=[
                '/bin/sh',
                '-c',
                'kill -s SIGINT 1',
            ],
            stderr=True,
            stdin=False,
            stdout=True,
            tty=False,
            _preload_content=True,
            _request_timeout=10,
        )

        return resp

    except JSONDecodeError:
        message = f'Failed to decode json document from pod: {pod.metadata.name}'
        self.log.exception(message)
        raise AirflowException(message)

    except Exception as e:
        message = f'Failed to extract xcom from pod: {pod.metadata.name}'
        self.log.exception(message)
        raise AirflowException(message)