<?php
/*
* Copyright 2016 Google LLC
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
namespace Google\ApiCore;
use Google\Rpc\Code;
/**
* BidiStream is the response object from a gRPC bidirectional streaming API call.
*/
class BidiStream
{
private $call;
private $isComplete = false;
private $writesClosed = false;
private $resourcesGetMethod = null;
private $pendingResources = [];
/**
* BidiStream constructor.
*
* @param \Grpc\BidiStreamingCall $bidiStreamingCall The gRPC bidirectional streaming call object
* @param array $streamingDescriptor
*/
public function __construct($bidiStreamingCall, array $streamingDescriptor = [])
{
$this->call = $bidiStreamingCall;
if (array_key_exists('resourcesGetMethod', $streamingDescriptor)) {
$this->resourcesGetMethod = $streamingDescriptor['resourcesGetMethod'];
}
}
/**
* Write request to the server.
*
* @param mixed $request The request to write
* @throws ValidationException
*/
public function write($request)
{
if ($this->isComplete) {
throw new ValidationException("Cannot call write() after streaming call is complete.");
}
if ($this->writesClosed) {
throw new ValidationException("Cannot call write() after calling closeWrite().");
}
$this->call->write($request);
}
/**
* Write all requests in $requests.
*
* @param mixed[] $requests An Iterable of request objects to write to the server
*
* @throws ValidationException
*/
public function writeAll($requests = [])
{
foreach ($requests as $request) {
$this->write($request);
}
}
/**
* Inform the server that no more requests will be written. The write() function cannot be
* called after closeWrite() is called.
* @throws ValidationException
*/
public function closeWrite()
{
if ($this->isComplete) {
throw new ValidationException(
"Cannot call closeWrite() after streaming call is complete."
);
}
if (!$this->writesClosed) {
$this->call->writesDone();
$this->writesClosed = true;
}
}
/**
* Read the next response from the server. Returns null if the streaming call completed
* successfully. Throws an ApiException if the streaming call failed.
*
* @throws ValidationException
* @throws ApiException
* @return mixed
*/
public function read()
{
if ($this->isComplete) {
throw new ValidationException("Cannot call read() after streaming call is complete.");
}
$resourcesGetMethod = $this->resourcesGetMethod;
if (!is_null($resourcesGetMethod)) {
if (count($this->pendingResources) === 0) {
$response = $this->call->read();
if (!is_null($response)) {
$pendingResources = [];
foreach ($response->$resourcesGetMethod() as $resource) {
$pendingResources[] = $resource;
}
$this->pendingResources = array_reverse($pendingResources);
}
}
$result = array_pop($this->pendingResources);
} else {
$result = $this->call->read();
}
if (is_null($result)) {
$status = $this->call->getStatus();
$this->isComplete = true;
if (!($status->code == Code::OK)) {
throw ApiException::createFromStdClass($status);
}
}
return $result;
}
/**
* Call closeWrite(), and read all responses from the server, until the streaming call is
* completed. Throws an ApiException if the streaming call failed.
*
* @throws ValidationException
* @throws ApiException
* @return \Generator|mixed[]
*/
public function closeWriteAndReadAll()
{
$this->closeWrite();
$response = $this->read();
while (!is_null($response)) {
yield $response;
$response = $this->read();
}
}
/**
* Return the underlying gRPC call object
*
* @return \Grpc\BidiStreamingCall|mixed
*/
public function getBidiStreamingCall()
{
return $this->call;
}
}