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arangodb/arangod/Cluster/AgencyComm.cpp

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////////////////////////////////////////////////////////////////////////////////
/// @brief communication with agency node(s)
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2010-2012 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 triAGENS GmbH, Cologne, Germany
///
/// @author Jan Steemann
/// @author Copyright 2013, triagens GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "Cluster/AgencyComm.h"
#include "Basics/JsonHelper.h"
#include "Basics/ReadLocker.h"
#include "Basics/StringUtils.h"
#include "Basics/WriteLocker.h"
#include "BasicsC/json.h"
#include "BasicsC/logging.h"
#include "Cluster/ServerState.h"
#include "Rest/Endpoint.h"
#include "Rest/HttpRequest.h"
#include "SimpleHttpClient/GeneralClientConnection.h"
#include "SimpleHttpClient/SimpleHttpClient.h"
#include "SimpleHttpClient/SimpleHttpResult.h"
using namespace triagens::arango;
// -----------------------------------------------------------------------------
// --SECTION-- AgencyEndpoint
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors / destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief creates an agency endpoint
////////////////////////////////////////////////////////////////////////////////
AgencyEndpoint::AgencyEndpoint (triagens::rest::Endpoint* endpoint,
triagens::httpclient::GeneralClientConnection* connection)
: _endpoint(endpoint),
_connection(connection),
_busy(false) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys an agency endpoint
////////////////////////////////////////////////////////////////////////////////
AgencyEndpoint::~AgencyEndpoint () {
if (_connection != 0) {
delete _connection;
}
if (_endpoint != 0) {
delete _endpoint;
}
}
// -----------------------------------------------------------------------------
// --SECTION-- AgencyCommResult
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief constructs a communication result
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult::AgencyCommResult ()
: _location(),
_message(),
_body(),
_values(),
_index(0),
_statusCode(0),
_connected(false) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys a communication result
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult::~AgencyCommResult () {
// free all JSON data
std::map<std::string, AgencyCommResultEntry>::iterator it = _values.begin();
while (it != _values.end()) {
if ((*it).second._json != 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, (*it).second._json);
}
++it;
}
}
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief extract the connected flag from the result
////////////////////////////////////////////////////////////////////////////////
bool AgencyCommResult::connected () const {
return _connected;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief extract the http code from the result
////////////////////////////////////////////////////////////////////////////////
int AgencyCommResult::httpCode () const {
return _statusCode;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief extract the error code from the result
////////////////////////////////////////////////////////////////////////////////
int AgencyCommResult::errorCode () const {
int result = 0;
TRI_json_t* json = TRI_JsonString(TRI_UNKNOWN_MEM_ZONE, _body.c_str());
if (! TRI_IsArrayJson(json)) {
if (json != 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
}
return result;
}
// get "errorCode" attribute
TRI_json_t const* errorCode = TRI_LookupArrayJson(json, "errorCode");
if (TRI_IsNumberJson(errorCode)) {
result = (int) errorCode->_value._number;
}
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief extract the error message from the result
/// if there is no error, an empty string will be returned
////////////////////////////////////////////////////////////////////////////////
std::string AgencyCommResult::errorMessage () const {
std::string result;
if (! _message.empty()) {
// return stored message first if set
return _message;
}
if (! _connected) {
return std::string("unable to connect to agency");
}
TRI_json_t* json = TRI_JsonString(TRI_UNKNOWN_MEM_ZONE, _body.c_str());
if (0 == json) {
return std::string("Out of memory");
}
if (! TRI_IsArrayJson(json)) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
// get "message" attribute
TRI_json_t const* message = TRI_LookupArrayJson(json, "message");
if (TRI_IsStringJson(message)) {
result = std::string(message->_value._string.data, message->_value._string.length - 1);
}
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief extract the error details from the result
/// if there is no error, an empty string will be returned
////////////////////////////////////////////////////////////////////////////////
std::string AgencyCommResult::errorDetails () const {
const std::string errorMessage = this->errorMessage();
if (errorMessage.empty()) {
return _message;
}
return _message + " (" + errorMessage + ")";
}
////////////////////////////////////////////////////////////////////////////////
/// @brief flush the internal result buffer
////////////////////////////////////////////////////////////////////////////////
void AgencyCommResult::clear () {
// free existing values if any
std::map<std::string, AgencyCommResultEntry>::iterator it = _values.begin();
while (it != _values.end()) {
if ((*it).second._json != 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, (*it).second._json);
}
++it;
}
_values.clear();
_location = "";
_message = "";
_body = "";
_index = 0;
_statusCode = 0;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief recursively flatten the JSON response into a map
///
/// stripKeyPrefix is decoded, as is the _globalPrefix
////////////////////////////////////////////////////////////////////////////////
bool AgencyCommResult::parseJsonNode (TRI_json_t const* node,
std::string const& stripKeyPrefix,
bool withDirs) {
if (! TRI_IsArrayJson(node)) {
return true;
}
// get "key" attribute
TRI_json_t const* key = TRI_LookupArrayJson(node, "key");
if (! TRI_IsStringJson(key)) {
return false;
}
std::string keydecoded
= AgencyComm::decodeKey(std::string(key->_value._string.data,
key->_value._string.length-1));
// make sure we don't strip more bytes than the key is long
const size_t offset = AgencyComm::_globalPrefix.size() + stripKeyPrefix.size();
const size_t length = keydecoded.size();
std::string prefix;
if (offset >= length) {
prefix = "";
}
else {
prefix = keydecoded.substr(offset);
}
// get "dir" attribute
TRI_json_t const* dir = TRI_LookupArrayJson(node, "dir");
bool isDir = (TRI_IsBooleanJson(dir) && dir->_value._boolean);
if (isDir) {
if (withDirs) {
AgencyCommResultEntry entry;
entry._index = 0;
entry._json = 0;
entry._isDir = true;
_values.insert(std::make_pair(prefix, entry));
}
// is a directory, so there may be a "nodes" attribute
TRI_json_t const* nodes = TRI_LookupArrayJson(node, "nodes");
if (! TRI_IsListJson(nodes)) {
// if directory is empty...
return true;
}
const size_t n = TRI_LengthVector(&nodes->_value._objects);
for (size_t i = 0; i < n; ++i) {
if (! parseJsonNode((TRI_json_t const*) TRI_AtVector(&nodes->_value._objects, i),
stripKeyPrefix,
withDirs)) {
return false;
}
}
}
else {
// not a directory
// get "value" attribute
TRI_json_t const* value = TRI_LookupArrayJson(node, "value");
if (TRI_IsStringJson(value)) {
if (! prefix.empty()) {
AgencyCommResultEntry entry;
// get "modifiedIndex"
entry._index = triagens::basics::JsonHelper::stringUInt64(node, "modifiedIndex");
entry._json = triagens::basics::JsonHelper::fromString(value->_value._string.data, value->_value._string.length - 1);
entry._isDir = false;
_values.insert(std::make_pair(prefix, entry));
}
}
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// parse an agency result
/// note that stripKeyPrefix is a decoded, normal key!
////////////////////////////////////////////////////////////////////////////////
bool AgencyCommResult::parse (std::string const& stripKeyPrefix,
bool withDirs) {
TRI_json_t* json = TRI_JsonString(TRI_UNKNOWN_MEM_ZONE, _body.c_str());
if (! TRI_IsArrayJson(json)) {
if (json != 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
}
return false;
}
// get "node" attribute
TRI_json_t const* node = TRI_LookupArrayJson(json, "node");
const bool result = parseJsonNode(node, stripKeyPrefix, withDirs);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
// -----------------------------------------------------------------------------
// --SECTION-- AgencyComm
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- static variables
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief the static global URL prefix
////////////////////////////////////////////////////////////////////////////////
const std::string AgencyComm::AGENCY_URL_PREFIX = "v2/keys";
////////////////////////////////////////////////////////////////////////////////
/// @brief global (variable) prefix used for endpoint
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::_globalPrefix = "";
////////////////////////////////////////////////////////////////////////////////
/// @brief lock for the global endpoints
////////////////////////////////////////////////////////////////////////////////
triagens::basics::ReadWriteLock AgencyComm::_globalLock;
////////////////////////////////////////////////////////////////////////////////
/// @brief list of global endpoints
////////////////////////////////////////////////////////////////////////////////
std::list<AgencyEndpoint*> AgencyComm::_globalEndpoints;
////////////////////////////////////////////////////////////////////////////////
/// @brief global connection options
////////////////////////////////////////////////////////////////////////////////
AgencyConnectionOptions AgencyComm::_globalConnectionOptions = {
15.0, // connectTimeout
3.0, // requestTimeout
5.0, // lockTimeout
3 // numRetries
};
// -----------------------------------------------------------------------------
// --SECTION-- AgencyCommLocker
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief constructs an agency comm locker
////////////////////////////////////////////////////////////////////////////////
AgencyCommLocker::AgencyCommLocker (std::string const& key,
std::string const& type,
double ttl)
: _key(key),
_type(type),
_json(0),
_version(0),
_isLocked(false) {
AgencyComm comm;
_json = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, type.c_str(), type.size());
if (_json == 0) {
return;
}
if (comm.lock(key, ttl, 0.0, _json)) {
fetchVersion(comm);
_isLocked = true;
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys an agency comm locker
////////////////////////////////////////////////////////////////////////////////
AgencyCommLocker::~AgencyCommLocker () {
unlock();
if (_json != 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, _json);
}
}
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief unlocks the lock
////////////////////////////////////////////////////////////////////////////////
void AgencyCommLocker::unlock () {
if (_isLocked) {
AgencyComm comm;
updateVersion(comm);
if (comm.unlock(_key, _json, 0.0)) {
_isLocked = false;
}
}
}
// -----------------------------------------------------------------------------
// --SECTION-- private functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief fetch a lock version from the agency
////////////////////////////////////////////////////////////////////////////////
bool AgencyCommLocker::fetchVersion (AgencyComm& comm) {
if (_type != "WRITE") {
return true;
}
AgencyCommResult result = comm.getValues(_key + "/Version", false);
if (! result.successful()) {
if (result.httpCode() != (int) triagens::rest::HttpResponse::NOT_FOUND) {
return false;
}
return true;
}
result.parse("", false);
std::map<std::string, AgencyCommResultEntry>::const_iterator it = result._values.begin();
if (it == result._values.end()) {
return false;
}
_version = triagens::basics::JsonHelper::stringUInt64((*it).second._json);
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief update a lock version in the agency
////////////////////////////////////////////////////////////////////////////////
bool AgencyCommLocker::updateVersion (AgencyComm& comm) {
if (_type != "WRITE") {
return true;
}
if (_version == 0) {
TRI_json_t* json = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, 1);
if (json == 0) {
return false;
}
// no Version key found, now set it
AgencyCommResult result = comm.casValue(_key + "/Version",
json,
false,
0.0,
0.0);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result.successful();
}
else {
// Version key found, now update it
TRI_json_t* oldJson = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, _version);
if (oldJson == 0) {
return false;
}
TRI_json_t* newJson = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, _version + 1);
if (newJson == 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
return false;
}
AgencyCommResult result = comm.casValue(_key + "/Version",
oldJson,
newJson,
0.0,
0.0);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, newJson);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
return result.successful();
}
}
// -----------------------------------------------------------------------------
// --SECTION-- AgencyComm
// -----------------------------------------------------------------------------
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief constructs an agency communication object
////////////////////////////////////////////////////////////////////////////////
AgencyComm::AgencyComm (bool addNewEndpoints)
: _addNewEndpoints(addNewEndpoints) {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys an agency communication object
////////////////////////////////////////////////////////////////////////////////
AgencyComm::~AgencyComm () {
}
// -----------------------------------------------------------------------------
// --SECTION-- public static methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief cleans up all connections
////////////////////////////////////////////////////////////////////////////////
void AgencyComm::cleanup () {
AgencyComm::disconnect();
{
WRITE_LOCKER(AgencyComm::_globalLock);
std::list<AgencyEndpoint*>::iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
delete agencyEndpoint;
++it;
}
// empty the list
_globalEndpoints.clear();
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief tries to establish a communication channel
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::tryConnect () {
{
WRITE_LOCKER(AgencyComm::_globalLock);
if (_globalEndpoints.size() == 0) {
return false;
}
std::list<AgencyEndpoint*>::iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
assert(agencyEndpoint->_endpoint != 0);
assert(agencyEndpoint->_connection != 0);
if (agencyEndpoint->_endpoint->isConnected()) {
return true;
}
agencyEndpoint->_endpoint->connect(_globalConnectionOptions._connectTimeout,
_globalConnectionOptions._requestTimeout);
if (agencyEndpoint->_endpoint->isConnected()) {
return true;
}
++it;
}
}
// unable to connect to any endpoint
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief disconnects all communication channels
////////////////////////////////////////////////////////////////////////////////
void AgencyComm::disconnect () {
WRITE_LOCKER(AgencyComm::_globalLock);
std::list<AgencyEndpoint*>::iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
assert(agencyEndpoint->_connection != 0);
assert(agencyEndpoint->_endpoint != 0);
agencyEndpoint->_connection->disconnect();
agencyEndpoint->_endpoint->disconnect();
++it;
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief adds an endpoint to the endpoints list
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::addEndpoint (std::string const& endpointSpecification,
bool toFront) {
LOG_TRACE("adding global agency-endpoint '%s'", endpointSpecification.c_str());
{
WRITE_LOCKER(AgencyComm::_globalLock);
// check if we already have got this endpoint
std::list<AgencyEndpoint*>::const_iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint const* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
if (agencyEndpoint->_endpoint->getSpecification() == endpointSpecification) {
// a duplicate. just ignore
return false;
}
++it;
}
// didn't find the endpoint in our list of endpoints, so now create a new one
for (size_t i = 0; i < NumConnections; ++i) {
AgencyEndpoint* agencyEndpoint = createAgencyEndpoint(endpointSpecification);
if (agencyEndpoint == 0) {
return false;
}
if (toFront) {
AgencyComm::_globalEndpoints.push_front(agencyEndpoint);
}
else {
AgencyComm::_globalEndpoints.push_back(agencyEndpoint);
}
}
}
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes an endpoint from the endpoints list
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::removeEndpoint (std::string const& endpointSpecification) {
LOG_TRACE("removing global agency-endpoint '%s'", endpointSpecification.c_str());
{
WRITE_LOCKER(AgencyComm::_globalLock);
// check if we have got this endpoint
std::list<AgencyEndpoint*>::iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint const* agencyEndpoint = (*it);
if (agencyEndpoint->_endpoint->getSpecification() == endpointSpecification) {
// found, now remove
AgencyComm::_globalEndpoints.erase(it);
// and get rid of the endpoint
delete agencyEndpoint;
return true;
}
++it;
}
}
// not found
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief checks if an endpoint is present
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::hasEndpoint (std::string const& endpointSpecification) {
{
READ_LOCKER(AgencyComm::_globalLock);
// check if we have got this endpoint
std::list<AgencyEndpoint*>::iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint const* agencyEndpoint = (*it);
if (agencyEndpoint->_endpoint->getSpecification() == endpointSpecification) {
return true;
}
++it;
}
}
// not found
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get a stringified version of the endpoints
////////////////////////////////////////////////////////////////////////////////
const std::vector<std::string> AgencyComm::getEndpoints () {
std::vector<std::string> result;
{
// iterate over the list of endpoints
READ_LOCKER(AgencyComm::_globalLock);
std::list<AgencyEndpoint*>::const_iterator it = AgencyComm::_globalEndpoints.begin();
while (it != AgencyComm::_globalEndpoints.end()) {
AgencyEndpoint const* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
result.push_back(agencyEndpoint->_endpoint->getSpecification());
++it;
}
}
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get a stringified version of the endpoints
////////////////////////////////////////////////////////////////////////////////
const std::string AgencyComm::getEndpointsString () {
std::string result;
{
// iterate over the list of endpoints
READ_LOCKER(AgencyComm::_globalLock);
std::list<AgencyEndpoint*>::const_iterator it = AgencyComm::_globalEndpoints.begin();
while (it != AgencyComm::_globalEndpoints.end()) {
if (! result.empty()) {
result += ", ";
}
AgencyEndpoint const* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
result.append(agencyEndpoint->_endpoint->getSpecification());
++it;
}
}
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief sets the global prefix for all operations
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::setPrefix (std::string const& prefix) {
// agency prefix must not be changed
_globalPrefix = prefix;
// make sure prefix starts with a forward slash
if (prefix[0] != '/') {
_globalPrefix = '/' + _globalPrefix;
}
// make sure prefix ends with a forward slash
if (_globalPrefix.size() > 0) {
if (_globalPrefix[_globalPrefix.size() - 1] != '/') {
_globalPrefix += '/';
}
}
LOG_TRACE("setting agency-prefix to '%s'", prefix.c_str());
return true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief gets the global prefix for all operations
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::prefix () {
return _globalPrefix;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief generate a timestamp
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::generateStamp () {
time_t tt = time(0);
struct tm tb;
char buffer[21];
// TODO: optimise this
TRI_gmtime(tt, &tb);
size_t len = ::strftime(buffer, sizeof(buffer), "%Y-%m-%dT%H:%M:%SZ", &tb);
return std::string(buffer, len);
}
// -----------------------------------------------------------------------------
// --SECTION-- private static methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a new agency endpoint
////////////////////////////////////////////////////////////////////////////////
AgencyEndpoint* AgencyComm::createAgencyEndpoint (std::string const& endpointSpecification) {
triagens::rest::Endpoint* endpoint = triagens::rest::Endpoint::clientFactory(endpointSpecification);
if (endpoint == 0) {
// could not create endpoint...
return 0;
}
triagens::httpclient::GeneralClientConnection* connection =
triagens::httpclient::GeneralClientConnection::factory(endpoint,
_globalConnectionOptions._requestTimeout,
_globalConnectionOptions._connectTimeout,
_globalConnectionOptions._connectRetries,
0);
if (connection == 0) {
delete endpoint;
return 0;
}
return new AgencyEndpoint(endpoint, connection);
}
// -----------------------------------------------------------------------------
// --SECTION-- public methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief sends the current server state to the agency
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::sendServerState (double ttl) {
// construct JSON value { "status": "...", "time": "..." }
TRI_json_t* json = TRI_CreateArrayJson(TRI_UNKNOWN_MEM_ZONE);
if (json == 0) {
return AgencyCommResult();
}
const std::string status = ServerState::stateToString(ServerState::instance()->getState());
const std::string stamp = AgencyComm::generateStamp();
TRI_Insert3ArrayJson(TRI_UNKNOWN_MEM_ZONE, json, "status", TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, status.c_str(), status.size()));
TRI_Insert3ArrayJson(TRI_UNKNOWN_MEM_ZONE, json, "time", TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, stamp.c_str(), stamp.size()));
AgencyCommResult result(setValue("Sync/ServerStates/" + ServerState::instance()->getId(), json, ttl));
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief gets the backend version
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::getVersion () {
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_GET,
_globalConnectionOptions._requestTimeout,
result,
"version",
"",
false);
if (result.successful()) {
return result._body;
}
return "";
}
////////////////////////////////////////////////////////////////////////////////
/// @brief update a version number in the agency
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::increaseVersion (std::string const& key) {
// fetch existing version number
AgencyCommResult result = getValues(key, false);
if (! result.successful()) {
if (result.httpCode() != (int) triagens::rest::HttpResponse::NOT_FOUND) {
return false;
}
// no version key found, now set it
TRI_json_t* json = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, 1);
if (json == 0) {
return false;
}
result.clear();
result = casValue(key,
json,
false,
0.0,
0.0);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result.successful();
}
// found a version
result.parse("", false);
std::map<std::string, AgencyCommResultEntry>::const_iterator it = result._values.begin();
if (it == result._values.end()) {
return false;
}
uint64_t version = triagens::basics::JsonHelper::stringUInt64((*it).second._json);
// version key found, now update it
TRI_json_t* oldJson = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, version);
if (oldJson == 0) {
return false;
}
TRI_json_t* newJson = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, version + 1);
if (newJson == 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
return false;
}
result.clear();
result = casValue(key,
oldJson,
newJson,
0.0,
0.0);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, newJson);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
return result.successful();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a directory in the backend
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::createDirectory (std::string const& key) {
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_PUT,
_globalConnectionOptions._requestTimeout,
result,
buildUrl(key) + "?dir=true",
"",
false);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief sets a value in the backend
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::setValue (std::string const& key,
TRI_json_t const* json,
double ttl) {
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_PUT,
_globalConnectionOptions._requestTimeout,
result,
buildUrl(key) + ttlParam(ttl, true),
"value=" + triagens::basics::StringUtils::urlEncode(triagens::basics::JsonHelper::toString(json)),
false);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief checks if a key exists
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::exists (std::string const& key) {
std::string url(buildUrl(key));
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_GET,
_globalConnectionOptions._requestTimeout,
result,
url,
"",
false);
return result.successful();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief gets one or multiple values from the backend
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::getValues (std::string const& key,
bool recursive) {
std::string url(buildUrl(key));
if (recursive) {
url += "?recursive=true";
}
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_GET,
_globalConnectionOptions._requestTimeout,
result,
url,
"",
false);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief removes one or multiple values from the backend
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::removeValues (std::string const& key,
bool recursive) {
std::string url;
if (key.empty() && recursive) {
// delete everything, recursive
url = buildUrl();
}
else {
url = buildUrl(key);
}
if (recursive) {
url += "?recursive=true";
}
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_DELETE,
_globalConnectionOptions._requestTimeout,
result,
url,
"",
false);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief compares and swaps a single value in the backend
/// the CAS condition is whether or not a previous value existed for the key
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::casValue (std::string const& key,
TRI_json_t const* json,
bool prevExist,
double ttl,
double timeout) {
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_PUT,
timeout == 0.0 ? _globalConnectionOptions._requestTimeout : timeout,
result,
buildUrl(key) + "?prevExist="
+ (prevExist ? "true" : "false") + ttlParam(ttl, false),
"value=" + triagens::basics::StringUtils::urlEncode(triagens::basics::JsonHelper::toString(json)),
false);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief compares and swaps a single value in the backend
/// the CAS condition is whether or not the previous value for the key was
/// identical to `oldValue`
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::casValue (std::string const& key,
TRI_json_t const* oldJson,
TRI_json_t const* newJson,
double ttl,
double timeout) {
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_PUT,
timeout == 0.0 ? _globalConnectionOptions._requestTimeout : timeout,
result,
buildUrl(key) + "?prevValue="
+ triagens::basics::StringUtils::urlEncode(triagens::basics::JsonHelper::toString(oldJson))
+ ttlParam(ttl, false),
"value=" + triagens::basics::StringUtils::urlEncode(triagens::basics::JsonHelper::toString(newJson)),
false);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief blocks on a change of a single value in the backend
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::watchValue (std::string const& key,
uint64_t waitIndex,
double timeout,
bool recursive) {
std::string url(buildUrl(key) + "?wait=true");
if (waitIndex > 0) {
url += "&waitIndex=" + triagens::basics::StringUtils::itoa(waitIndex);
}
if (recursive) {
url += "&recursive=true";
}
AgencyCommResult result;
sendWithFailover(triagens::rest::HttpRequest::HTTP_REQUEST_GET,
timeout == 0.0 ? _globalConnectionOptions._requestTimeout : timeout,
result,
url,
"",
true);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief acquire a read lock
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::lockRead (std::string const& key,
double ttl,
double timeout) {
TRI_json_t* json = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "READ", 4);
if (json == 0) {
return false;
}
bool result = lock(key, ttl, timeout, json);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief acquire a write lock
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::lockWrite (std::string const& key,
double ttl,
double timeout) {
TRI_json_t* json = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "WRITE", 5);
if (json == 0) {
return false;
}
bool result = lock(key, ttl, timeout, json);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief release a read lock
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::unlockRead (std::string const& key,
double timeout) {
TRI_json_t* json = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "READ", 4);
if (json == 0) {
return false;
}
bool result = unlock(key, json, timeout);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief release a write lock
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::unlockWrite (std::string const& key,
double timeout) {
TRI_json_t* json = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "WRITE", 5);
if (json == 0) {
return false;
}
bool result = unlock(key, json, timeout);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get unique id
////////////////////////////////////////////////////////////////////////////////
AgencyCommResult AgencyComm::uniqid (std::string const& key,
uint64_t count,
double timeout) {
static const int maxTries = 10;
int tries = 0;
AgencyCommResult result;
while (tries++ < maxTries) {
result.clear();
result = getValues(key, false);
if (result.httpCode() == (int) triagens::rest::HttpResponse::NOT_FOUND) {
TRI_json_t* json = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "0", 1);
if (json != 0) {
// create the key on the fly
setValue(key, json, 0.0);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, json);
tries--;
continue;
}
}
if (! result.successful()) {
return result;
}
result.parse("", false);
TRI_json_t* oldJson = 0;
std::map<std::string, AgencyCommResultEntry>::iterator it = result._values.begin();
if (it != result._values.end()) {
// steal the json
oldJson = (*it).second._json;
(*it).second._json = 0;
}
else {
oldJson = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "0", 1);
}
if (oldJson == 0) {
return AgencyCommResult();
}
const uint64_t oldValue = triagens::basics::JsonHelper::stringUInt64(oldJson) + count;
const uint64_t newValue = oldValue + count;
TRI_json_t* newJson = triagens::basics::JsonHelper::uint64String(TRI_UNKNOWN_MEM_ZONE, newValue);
if (newJson == 0) {
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
return AgencyCommResult();
}
result.clear();
result = casValue(key, oldJson, newJson, 0.0, timeout);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, newJson);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
if (result.successful()) {
result._index = oldValue + 1;
break;
}
}
return result;
}
// -----------------------------------------------------------------------------
// --SECTION-- private methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a ttl URL parameter
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::ttlParam (double ttl,
bool isFirst) {
if (ttl <= 0.0) {
return "";
}
return (isFirst ? "?ttl=" : "&ttl=") + triagens::basics::StringUtils::itoa((int) ttl);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief acquires a lock
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::lock (std::string const& key,
double ttl,
double timeout,
TRI_json_t const* json) {
if (ttl == 0.0) {
ttl = _globalConnectionOptions._lockTimeout;
}
if (timeout == 0.0) {
timeout = _globalConnectionOptions._lockTimeout;
}
const double end = TRI_microtime() + timeout;
while (true) {
TRI_json_t* oldJson = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "UNLOCKED", 8);
if (oldJson == 0) {
return false;
}
AgencyCommResult result = casValue(key + "/Lock",
oldJson,
json,
ttl,
timeout);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, oldJson);
if (! result.successful() &&
result.httpCode() == (int) triagens::rest::HttpResponse::NOT_FOUND) {
// key does not yet exist. create it now
result = casValue(key + "/Lock",
json,
false,
ttl,
timeout);
}
if (result.successful()) {
return true;
}
usleep(1000);
const double now = TRI_microtime();
if (now >= end) {
return false;
}
}
assert(false);
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief releases a lock
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::unlock (std::string const& key,
TRI_json_t const* json,
double timeout) {
if (timeout == 0.0) {
timeout = _globalConnectionOptions._lockTimeout;
}
const double end = TRI_microtime() + timeout;
while (true) {
TRI_json_t* newJson = TRI_CreateString2CopyJson(TRI_UNKNOWN_MEM_ZONE, "UNLOCKED", 8);
if (newJson == 0) {
return false;
}
AgencyCommResult result = casValue(key + "/Lock",
json,
newJson,
0.0,
timeout);
TRI_FreeJson(TRI_UNKNOWN_MEM_ZONE, newJson);
if (result.successful()) {
return true;
}
usleep(1000);
const double now = TRI_microtime();
if (now >= end) {
return false;
}
}
assert(false);
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief pop an endpoint from the queue
////////////////////////////////////////////////////////////////////////////////
AgencyEndpoint* AgencyComm::popEndpoint (std::string const& endpoint) {
while (1) {
{
WRITE_LOCKER(AgencyComm::_globalLock);
const size_t numEndpoints = _globalEndpoints.size();
std::list<AgencyEndpoint*>::iterator it = _globalEndpoints.begin();
while (it != _globalEndpoints.end()) {
AgencyEndpoint* agencyEndpoint = (*it);
assert(agencyEndpoint != 0);
if (! endpoint.empty() &&
agencyEndpoint->_endpoint->getSpecification() != endpoint) {
// we're looking for a different endpoint
++it;
continue;
}
if (! agencyEndpoint->_busy) {
agencyEndpoint->_busy = true;
if (AgencyComm::_globalEndpoints.size() > 1) {
// remove from list
AgencyComm::_globalEndpoints.remove(agencyEndpoint);
// and re-insert at end
AgencyComm::_globalEndpoints.push_back(agencyEndpoint);
}
assert(_globalEndpoints.size() == numEndpoints);
return agencyEndpoint;
}
++it;
}
}
// if we got here, we ran out of non-busy connections...
usleep(1000);
}
// just to shut up compilers
assert(false);
return 0;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief reinsert an endpoint into the queue
////////////////////////////////////////////////////////////////////////////////
void AgencyComm::requeueEndpoint (AgencyEndpoint* agencyEndpoint,
bool wasWorking) {
WRITE_LOCKER(AgencyComm::_globalLock);
const size_t numEndpoints = _globalEndpoints.size();
assert(agencyEndpoint != 0);
assert(agencyEndpoint->_busy);
// set to non-busy
agencyEndpoint->_busy = false;
if (AgencyComm::_globalEndpoints.size() > 1) {
if (wasWorking) {
// remove from list
AgencyComm::_globalEndpoints.remove(agencyEndpoint);
// and re-insert at front
AgencyComm::_globalEndpoints.push_front(agencyEndpoint);
}
}
assert(_globalEndpoints.size() == numEndpoints);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief construct a URL
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::buildUrl (std::string const& relativePart) const {
return AgencyComm::AGENCY_URL_PREFIX +encodeKey(_globalPrefix + relativePart);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief construct a URL, without a key
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::buildUrl () const {
return AgencyComm::AGENCY_URL_PREFIX
+ encodeKey(_globalPrefix.substr(0, _globalPrefix.size() - 1));
}
////////////////////////////////////////////////////////////////////////////////
/// @brief sends an HTTP request to the agency, handling failover
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::sendWithFailover (triagens::rest::HttpRequest::HttpRequestType method,
const double timeout,
AgencyCommResult& result,
std::string const& url,
std::string const& body,
bool isWatch) {
size_t numEndpoints;
{
READ_LOCKER(AgencyComm::_globalLock);
numEndpoints = AgencyComm::_globalEndpoints.size();
if (numEndpoints == 0) {
return false;
}
}
assert(numEndpoints > 0);
size_t tries = 0;
std::string realUrl = url;
std::string forceEndpoint = "";
while (tries++ < numEndpoints) {
AgencyEndpoint* agencyEndpoint = popEndpoint(forceEndpoint);
assert(agencyEndpoint != 0);
send(agencyEndpoint->_connection,
method,
timeout,
result,
realUrl,
body);
if (result._statusCode == (int) triagens::rest::HttpResponse::TEMPORARY_REDIRECT) {
// sometimes the agency will return a 307 (temporary redirect)
// in this case we have to pick it up and use the new location returned
// put the current connection to the end of the list
requeueEndpoint(agencyEndpoint, false);
// a 307 does not count as a success
assert(! result.successful());
std::string endpoint;
// transform location into an endpoint
if (result.location().substr(0, 7) == "http://") {
endpoint = "tcp://" + result.location().substr(7);
}
else if (result.location().substr(0, 8) == "https://") {
endpoint = "ssl://" + result.location().substr(8);
}
else {
// invalid endpoint, return an error
return false;
}
const size_t delim = endpoint.find('/', 6);
if (delim == std::string::npos) {
// invalid location header
return false;
}
realUrl = endpoint.substr(delim);
endpoint = endpoint.substr(0, delim);
if (! AgencyComm::hasEndpoint(endpoint)) {
// redirection to an unknown endpoint
if (_addNewEndpoints) {
AgencyComm::addEndpoint(endpoint, true);
LOG_INFO("adding agency-endpoint '%s'", endpoint.c_str());
// re-check the new endpoint
if (AgencyComm::hasEndpoint(endpoint)) {
++numEndpoints;
continue;
}
}
LOG_ERROR("found redirection to unknown endpoint '%s'. Will not follow!",
endpoint.c_str());
// this is an error
return false;
}
forceEndpoint = endpoint;
// if we get here, we'll just use the next endpoint from the list
continue;
}
forceEndpoint = "";
// we can stop iterating over endpoints if the operation succeeded,
// if a watch timed out or
// if the reason for failure was a client-side error
const bool canAbort = result.successful() ||
(isWatch && result._statusCode == 0) ||
(result._statusCode >= 400 && result._statusCode <= 499);
requeueEndpoint(agencyEndpoint, canAbort);
if (canAbort) {
// we're done
return true;
}
// otherwise, try next
}
// if we get here, we could not send data to any endpoint successfully
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief sends data to the URL
////////////////////////////////////////////////////////////////////////////////
bool AgencyComm::send (triagens::httpclient::GeneralClientConnection* connection,
triagens::rest::HttpRequest::HttpRequestType method,
double timeout,
AgencyCommResult& result,
std::string const& url,
std::string const& body) {
assert(connection != 0);
if (method == triagens::rest::HttpRequest::HTTP_REQUEST_GET ||
method == triagens::rest::HttpRequest::HTTP_REQUEST_HEAD ||
method == triagens::rest::HttpRequest::HTTP_REQUEST_DELETE) {
assert(body.empty());
}
assert(! url.empty());
result._connected = false;
result._statusCode = 0;
LOG_TRACE("sending %s request to agency at endpoint '%s', url '%s': %s",
triagens::rest::HttpRequest::translateMethod(method).c_str(),
connection->getEndpoint()->getSpecification().c_str(),
url.c_str(),
body.c_str());
triagens::httpclient::SimpleHttpClient client(connection,
timeout,
false);
client.keepConnectionOnDestruction(true);
// set up headers
std::map<std::string, std::string> headers;
if (method == triagens::rest::HttpRequest::HTTP_REQUEST_PUT ||
method == triagens::rest::HttpRequest::HTTP_REQUEST_POST) {
// the agency needs this content-type for the body
headers["content-type"] = "application/x-www-form-urlencoded";
}
// send the actual request
triagens::httpclient::SimpleHttpResult* response = client.request(method,
url,
body.c_str(),
body.size(),
headers);
if (response == 0) {
result._message = "could not send request to agency";
LOG_TRACE("sending request to agency failed");
return false;
}
if (! response->isComplete()) {
result._message = "sending request to agency failed";
LOG_TRACE("sending request to agency failed");
delete response;
return false;
}
result._connected = true;
if (response->getHttpReturnCode() == (int) triagens::rest::HttpResponse::TEMPORARY_REDIRECT) {
// temporary redirect. now save location header
bool found = false;
result._location = response->getHeaderField("location", found);
LOG_TRACE("redirecting to location: '%s'", result._location.c_str());
if (! found) {
// a 307 without a location header does not make any sense
delete response;
result._message = "invalid agency response (header missing)";
return false;
}
}
result._message = response->getHttpReturnMessage();
result._body = response->getBody().str();
result._index = 0;
result._statusCode = response->getHttpReturnCode();
bool found = false;
std::string lastIndex = response->getHeaderField("x-etcd-index", found);
if (found) {
result._index = triagens::basics::StringUtils::uint64(lastIndex);
}
LOG_TRACE("request to agency returned status code %d, message: '%s', body: '%s'",
result._statusCode,
result._message.c_str(),
result._body.c_str());
delete response;
return result.successful();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief encode a key for etcd
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::encodeKey (std::string s) {
string::iterator i;
string res;
for (i = s.begin(); i != s.end(); ++i) {
if (*i == '_') {
res.push_back('@');
res.push_back('U');
}
else if (*i == '@') {
res.push_back('@');
res.push_back('@');
}
else {
res.push_back(*i);
}
}
return res;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief decode a key for etcd
////////////////////////////////////////////////////////////////////////////////
std::string AgencyComm::decodeKey (std::string s) {
string::iterator i;
string res;
for (i = s.begin(); i != s.end(); ++i) {
if (*i == '@') {
++i;
if (*i == 'U') {
res.push_back('_');
}
else {
res.push_back('@');
}
}
else {
res.push_back(*i);
}
}
return res;
}
// Local Variables:
// mode: outline-minor
// outline-regexp: "^\\(/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|// --SECTION--\\|/// @\\}\\)"
// End:
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