1
0
Fork 0
arangodb/arangod/HttpServer/AsyncJobManager.cpp

444 lines
14 KiB
C++

////////////////////////////////////////////////////////////////////////////////
/// @brief job manager
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2014-2015 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Jan Steemann
/// @author Copyright 2014-2015, ArangoDB GmbH, Cologne, Germany
/// @author Copyright 2004-2014, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "AsyncJobManager.h"
#include "Basics/ReadLocker.h"
#include "Basics/WriteLocker.h"
#include "Basics/logging.h"
#include "HttpServer/HttpHandler.h"
#include "HttpServer/HttpServerJob.h"
using namespace triagens::basics;
using namespace triagens::rest;
using namespace std;
// -----------------------------------------------------------------------------
// --SECTION-- class AsyncCallbackContext
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief AsyncCallbackContext
////////////////////////////////////////////////////////////////////////////////
class triagens::rest::AsyncCallbackContext {
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
public:
////////////////////////////////////////////////////////////////////////////////
/// @brief constructor
////////////////////////////////////////////////////////////////////////////////
AsyncCallbackContext (string const& coordHeader)
: _coordHeader(coordHeader),
_response(nullptr) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destructor
////////////////////////////////////////////////////////////////////////////////
~AsyncCallbackContext () {
if (_response != nullptr) {
delete _response;
}
}
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
public:
////////////////////////////////////////////////////////////////////////////////
/// @brief gets the coordinator header
////////////////////////////////////////////////////////////////////////////////
string& getCoordinatorHeader () {
return _coordHeader;
}
// -----------------------------------------------------------------------------
// --SECTION-- private variables
// -----------------------------------------------------------------------------
private:
////////////////////////////////////////////////////////////////////////////////
/// @brief coordinator header
////////////////////////////////////////////////////////////////////////////////
string _coordHeader;
////////////////////////////////////////////////////////////////////////////////
/// @brief http response
////////////////////////////////////////////////////////////////////////////////
HttpResponse* _response;
};
// -----------------------------------------------------------------------------
// --SECTION-- class AsyncJobResult
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief constructor for an unspecified job result
////////////////////////////////////////////////////////////////////////////////
AsyncJobResult::AsyncJobResult ()
: _jobId(0),
_response(nullptr),
_stamp(0.0),
_status(JOB_UNDEFINED),
_ctx(nullptr) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief constructor for a specific job result
////////////////////////////////////////////////////////////////////////////////
AsyncJobResult::AsyncJobResult (IdType jobId,
HttpResponse* response,
double stamp,
Status status,
AsyncCallbackContext* ctx)
: _jobId(jobId),
_response(response),
_stamp(stamp),
_status(status),
_ctx(ctx) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destructor
////////////////////////////////////////////////////////////////////////////////
AsyncJobResult::~AsyncJobResult () {
}
// -----------------------------------------------------------------------------
// --SECTION-- class AsyncJobManager
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief constructor
////////////////////////////////////////////////////////////////////////////////
AsyncJobManager::AsyncJobManager (generate_fptr idFunc, callback_fptr callback)
: _lock(),
_jobs(),
generate(idFunc),
callback(callback) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destructor
////////////////////////////////////////////////////////////////////////////////
AsyncJobManager::~AsyncJobManager () {
// remove all results that haven't been fetched
deleteJobResults();
}
// -----------------------------------------------------------------------------
// --SECTION-- public methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief returns the result of an async job
////////////////////////////////////////////////////////////////////////////////
HttpResponse* AsyncJobManager::getJobResult (AsyncJobResult::IdType jobId,
AsyncJobResult::Status& status,
bool removeFromList) {
WRITE_LOCKER(_lock);
auto it = _jobs.find(jobId);
if (it == _jobs.end()) {
status = AsyncJobResult::JOB_UNDEFINED;
return nullptr;
}
HttpResponse* response = (*it).second._response;
status = (*it).second._status;
if (status == AsyncJobResult::JOB_PENDING) {
return nullptr;
}
if (! removeFromList) {
return nullptr;
}
// remove the job from the list
_jobs.erase(it);
return response;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief deletes the result of an async job
////////////////////////////////////////////////////////////////////////////////
bool AsyncJobManager::deleteJobResult (AsyncJobResult::IdType jobId) {
WRITE_LOCKER(_lock);
auto it = _jobs.find(jobId);
if (it == _jobs.end()) {
return false;
}
HttpResponse* response = (*it).second._response;
if (response != nullptr) {
delete response;
}
// remove the job from the list
_jobs.erase(it);
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief deletes all results
////////////////////////////////////////////////////////////////////////////////
void AsyncJobManager::deleteJobResults () {
WRITE_LOCKER(_lock);
auto it = _jobs.begin();
while (it != _jobs.end()) {
HttpResponse* response = (*it).second._response;
if (response != nullptr) {
delete response;
}
++it;
}
_jobs.clear();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief deletes expired results
////////////////////////////////////////////////////////////////////////////////
void AsyncJobManager::deleteExpiredJobResults (double stamp) {
WRITE_LOCKER(_lock);
auto it = _jobs.begin();
while (it != _jobs.end()) {
AsyncJobResult ajr = (*it).second;
if (ajr._stamp < stamp) {
HttpResponse* response = ajr._response;
if (response != nullptr) {
delete response;
}
_jobs.erase(it++);
}
else {
++it;
}
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief returns the list of pending jobs
////////////////////////////////////////////////////////////////////////////////
const vector<AsyncJobResult::IdType> AsyncJobManager::pending (size_t maxCount) {
return byStatus(AsyncJobResult::JOB_PENDING, maxCount);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief returns the list of done jobs
////////////////////////////////////////////////////////////////////////////////
const vector<AsyncJobResult::IdType> AsyncJobManager::done (size_t maxCount) {
return byStatus(AsyncJobResult::JOB_DONE, maxCount);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief returns the list of jobs by status
////////////////////////////////////////////////////////////////////////////////
const vector<AsyncJobResult::IdType> AsyncJobManager::byStatus (AsyncJobResult::Status status,
size_t maxCount) {
vector<AsyncJobResult::IdType> jobs;
{
size_t n = 0;
READ_LOCKER(_lock);
auto it = _jobs.begin();
// iterate the list. the list is sorted by id
while (it != _jobs.end()) {
AsyncJobResult::IdType jobId = (*it).first;
if ((*it).second._status == status) {
jobs.emplace_back(jobId);
if (++n >= maxCount) {
break;
}
}
++it;
}
}
return jobs;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief initializes an async job
////////////////////////////////////////////////////////////////////////////////
void AsyncJobManager::initAsyncJob (HttpServerJob* job, uint64_t* jobId) {
if (jobId == nullptr) {
return;
}
TRI_ASSERT(job != nullptr);
*jobId = generate();
job->setId(*jobId);
AsyncCallbackContext* ctx = nullptr;
bool found;
char const* hdr = job->handler()->getRequest()->header("x-arango-coordinator", found);
if (found) {
LOG_DEBUG("Found header X-Arango-Coordinator in async request");
ctx = new AsyncCallbackContext(string(hdr));
}
AsyncJobResult ajr(*jobId,
nullptr,
TRI_microtime(),
AsyncJobResult::JOB_PENDING,
ctx);
WRITE_LOCKER(_lock);
_jobs.emplace(*jobId, ajr);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief finishes the execution of an async job
////////////////////////////////////////////////////////////////////////////////
void AsyncJobManager::finishAsyncJob (HttpServerJob* job) {
TRI_ASSERT(job != nullptr);
HttpHandler* handler = job->handler();
TRI_ASSERT(handler != nullptr);
AsyncJobResult::IdType jobId = job->id();
if (jobId == 0) {
return;
}
double const now = TRI_microtime();
AsyncCallbackContext* ctx = nullptr;
HttpResponse* response = nullptr;
{
WRITE_LOCKER(_lock);
auto it = _jobs.find(jobId);
if (it == _jobs.end()) {
// job is already deleted.
// do nothing here. the dispatcher will throw away the handler,
// which will also dispose the response
return;
}
else {
response = handler->stealResponse();
(*it).second._response = response;
(*it).second._status = AsyncJobResult::JOB_DONE;
(*it).second._stamp = now;
ctx = (*it).second._ctx;
if (ctx != nullptr) {
// we have found a context object, so we can immediately remove the job
// from the list of "done" jobs
_jobs.erase(it);
}
}
}
// If we got here, then we have stolen the pointer to the response
// If there is a callback context, the job is no longer in the
// list of "done" jobs, so we have to free the response and the
// callback context:
if (nullptr != ctx && nullptr != callback) {
callback(ctx->getCoordinatorHeader(), response);
delete ctx;
if (response != nullptr) {
delete response;
}
}
}
// -----------------------------------------------------------------------------
// --SECTION-- END-OF-FILE
// -----------------------------------------------------------------------------
// Local Variables:
// mode: outline-minor
// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @page\\|// --SECTION--\\|/// @\\}"
// End: