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arangodb/lib/SimpleHttpClient/SimpleHttpClient.cpp

889 lines
29 KiB
C++

////////////////////////////////////////////////////////////////////////////////
/// @brief simple http client
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2014 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 Dr. Frank Celler
/// @author Achim Brandt
/// @author Copyright 2014, ArangoDB GmbH, Cologne, Germany
/// @author Copyright 2009-2013, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "SimpleHttpClient.h"
#include "Basics/JsonHelper.h"
#include "Basics/logging.h"
#include "Basics/StringUtils.h"
#include "GeneralClientConnection.h"
#include "SimpleHttpResult.h"
using namespace triagens::basics;
using namespace triagens::rest;
using namespace std;
namespace triagens {
namespace httpclient {
////////////////////////////////////////////////////////////////////////////////
/// @brief empty map, used for headers
////////////////////////////////////////////////////////////////////////////////
std::map<std::string, std::string> const SimpleHttpClient::NoHeaders;
// -----------------------------------------------------------------------------
// constructors and destructors
// -----------------------------------------------------------------------------
SimpleHttpClient::SimpleHttpClient (GeneralClientConnection* connection,
double requestTimeout,
bool warn)
: _connection(connection),
_writeBuffer(TRI_UNKNOWN_MEM_ZONE),
_readBuffer(TRI_UNKNOWN_MEM_ZONE),
_readBufferOffset(0),
_requestTimeout(requestTimeout),
_state(IN_CONNECT),
_written(0),
_errorMessage(""),
_locationRewriter({nullptr, nullptr}),
_nextChunkedSize(0),
_result(nullptr),
_maxPacketSize(128 * 1024 * 1024),
_keepConnectionOnDestruction(false),
_warn(warn),
_keepAlive(true),
_exposeArangoDB(true),
_supportDeflate(true) {
TRI_ASSERT(connection != nullptr);
if (_connection->isConnected()) {
_state = FINISHED;
}
}
SimpleHttpClient::~SimpleHttpClient () {
// connection may have been invalidated by other objects
if (_connection != nullptr) {
if (! _keepConnectionOnDestruction || ! _connection->isConnected()) {
_connection->disconnect();
}
}
}
// -----------------------------------------------------------------------------
// public methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief close connection
////////////////////////////////////////////////////////////////////////////////
void SimpleHttpClient::close () {
// ensure connection has not yet been invalidated
TRI_ASSERT(_connection != nullptr);
_connection->disconnect();
_state = IN_CONNECT;
clearReadBuffer();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief send out a request, creating a new HttpResult object
/// this version does not allow specifying custom headers
////////////////////////////////////////////////////////////////////////////////
SimpleHttpResult* SimpleHttpClient::request (rest::HttpRequest::HttpRequestType method,
std::string const& location,
char const* body,
size_t bodyLength) {
return doRequest(method, location, body, bodyLength, NoHeaders);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief send out a request, creating a new HttpResult object
/// this version allows specifying custom headers
////////////////////////////////////////////////////////////////////////////////
SimpleHttpResult* SimpleHttpClient::request (rest::HttpRequest::HttpRequestType method,
std::string const& location,
char const* body,
size_t bodyLength,
std::map<std::string, std::string> const& headers) {
return doRequest(method, location, body, bodyLength, headers);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief send out a request, worker function
////////////////////////////////////////////////////////////////////////////////
SimpleHttpResult* SimpleHttpClient::doRequest (rest::HttpRequest::HttpRequestType method,
std::string const& location,
char const* body,
size_t bodyLength,
std::map<std::string, std::string> const& headers) {
// ensure connection has not yet been invalidated
TRI_ASSERT(_connection != nullptr);
// ensure that result is empty
TRI_ASSERT(_result == nullptr);
// create a new result
_result = new SimpleHttpResult;
// reset error message
_errorMessage = "";
// set body
setRequest(method, rewriteLocation(location), body, bodyLength, headers);
// ensure state
TRI_ASSERT(_state == IN_CONNECT || _state == IN_WRITE);
// respect timeout
double endTime = TRI_microtime() + _requestTimeout;
double remainingTime = _requestTimeout;
while (_state < FINISHED && remainingTime > 0.0) {
// Note that this loop can either be left by timeout or because
// a connect did not work (which sets the _state to DEAD). In all
// other error conditions we call close() which resets the state
// to IN_CONNECT and tries a reconnect. This is important because
// it is always possible that we are called with a connection that
// has already been closed by the other side. This leads to the
// strange effect that the write (if it is small enough) proceeds
// but the following read runs into an error. In that case we try
// to reconnect one and then give up if this does not work.
switch (_state) {
case (IN_CONNECT): {
handleConnect();
// If this goes wrong, _state is set to DEAD
break;
}
case (IN_WRITE): {
size_t bytesWritten = 0;
TRI_ASSERT(_writeBuffer.length() >= _written);
TRI_set_errno(TRI_ERROR_NO_ERROR);
bool res = _connection->handleWrite(
remainingTime,
static_cast<void const*>(_writeBuffer.c_str() + _written),
_writeBuffer.length() - _written,
&bytesWritten);
if (! res) {
setErrorMessage("Error writing to '" +
_connection->getEndpoint()->getSpecification() +
"' '" +
_connection->getErrorDetails() +
"'");
this->close(); // this sets _state to IN_CONNECT for a retry
}
else {
_written += bytesWritten;
if (_written == _writeBuffer.length()) {
_state = IN_READ_HEADER;
}
}
break;
}
case (IN_READ_HEADER):
case (IN_READ_BODY):
case (IN_READ_CHUNKED_HEADER):
case (IN_READ_CHUNKED_BODY): {
TRI_set_errno(TRI_ERROR_NO_ERROR);
// we need to notice if the other side has closed the connection:
bool connectionClosed;
bool res = _connection->handleRead(remainingTime,
_readBuffer,
connectionClosed);
// If there was an error, then we are doomed:
if (! res) {
setErrorMessage("Error reading from: '" +
_connection->getEndpoint()->getSpecification() +
"' '" +
_connection->getErrorDetails() +
"'");
this->close(); // this sets the state to IN_CONNECT for a retry
break;
}
if (connectionClosed) {
// write might have succeeded even if the server has closed
// the connection, this will then show up here with us being
// in state IN_READ_HEADER but nothing read.
if (_state == IN_READ_HEADER && 0 == _readBuffer.length()) {
this->close(); // sets _state to IN_CONNECT again for a retry
continue;
}
else if (_state == IN_READ_BODY && ! _result->hasContentLength()) {
// If we are reading the body and no content length was
// found in the header, then we must read until no more
// progress is made (but without an error), this then means
// that the server has closed the connection and we must
// process the body one more time:
_result->setContentLength(_readBuffer.length() - _readBufferOffset);
processBody();
if (_state != FINISHED) {
// If the body was not fully found we give up:
this->close(); // this sets the state IN_CONNECT to retry
}
break;
}
else {
// In all other cases of closed connection, we are doomed:
this->close(); // this sets the state to IN_CONNECT retry
break;
}
}
// the connection is still alive:
switch (_state) {
case (IN_READ_HEADER):
processHeader();
break;
case (IN_READ_BODY):
processBody();
break;
case (IN_READ_CHUNKED_HEADER):
processChunkedHeader();
break;
case (IN_READ_CHUNKED_BODY):
processChunkedBody();
break;
default:
break;
}
break;
}
default:
break;
}
remainingTime = endTime - TRI_microtime();
}
if (_state < FINISHED && _errorMessage.empty()) {
setErrorMessage("Request timeout reached");
}
// set result type in getResult()
SimpleHttpResult* result = getResult();
_result = nullptr;
return result;
}
// -----------------------------------------------------------------------------
// private methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief initialize the connection
////////////////////////////////////////////////////////////////////////////////
void SimpleHttpClient::handleConnect () {
// ensure connection has not yet been invalidated
TRI_ASSERT(_connection != nullptr);
if (! _connection->connect()) {
setErrorMessage("Could not connect to '" +
_connection->getEndpoint()->getSpecification() +
"' '" +
_connection->getErrorDetails() +
"'");
_state = DEAD;
}
else {
// can write now
_state = IN_WRITE;
_written = 0;
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief clearReadBuffer, clears the read buffer as well as the result
////////////////////////////////////////////////////////////////////////////////
void SimpleHttpClient::clearReadBuffer () {
_readBuffer.clear();
_readBufferOffset = 0;
if (_result) {
_result->clear();
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief sets username and password
////////////////////////////////////////////////////////////////////////////////
void SimpleHttpClient::setUserNamePassword (const string& prefix,
const string& username,
const string& password) {
string value = triagens::basics::StringUtils::encodeBase64(username + ":" + password);
_pathToBasicAuth.push_back(make_pair(prefix, value));
}
////////////////////////////////////////////////////////////////////////////////
/// @brief return the result
////////////////////////////////////////////////////////////////////////////////
SimpleHttpResult* SimpleHttpClient::getResult () {
switch (_state) {
case IN_WRITE:
_result->setResultType(SimpleHttpResult::WRITE_ERROR);
break;
case IN_READ_HEADER:
case IN_READ_BODY:
case IN_READ_CHUNKED_HEADER:
case IN_READ_CHUNKED_BODY:
_result->setResultType(SimpleHttpResult::READ_ERROR);
break;
case FINISHED:
_result->setResultType(SimpleHttpResult::COMPLETE);
break;
case IN_CONNECT:
default: {
_result->setResultType(SimpleHttpResult::COULD_NOT_CONNECT);
if (!haveErrorMessage()) {
setErrorMessage("Could not connect");
}
break;
}
}
if (haveErrorMessage() && (_result->getHttpReturnMessage().length() == 0)) {
_result->setHttpReturnMessage(_errorMessage);
}
return _result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief prepare a request
////////////////////////////////////////////////////////////////////////////////
void SimpleHttpClient::setRequest (rest::HttpRequest::HttpRequestType method,
std::string const& location,
char const* body,
size_t bodyLength,
std::map<std::string, std::string> const& headers) {
// clear read-buffer (no pipeling!)
_readBufferOffset = 0;
_readBuffer.reset();
// set HTTP method
_method = method;
// now fill the write buffer
_writeBuffer.clear();
// append method
HttpRequest::appendMethod(method, &_writeBuffer);
// append location
string l(location);
if (location.empty() || location[0] != '/') {
l = "/" + location;
}
_writeBuffer.appendText(l);
// append protocol
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR(" HTTP/1.1\r\n"));
// append hostname
string&& hostname = _connection->getEndpoint()->getHost();
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("Host: "));
_writeBuffer.appendText(hostname);
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("\r\n"));
if (_keepAlive) {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("Connection: Keep-Alive\r\n"));
}
else {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("Connection: Close\r\n"));
}
if (_exposeArangoDB) {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("User-Agent: ArangoDB\r\n"));
}
// do not automatically advertise deflate support
if (_supportDeflate) {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("Accept-Encoding: deflate\r\n"));
}
// do basic authorization
if (! _pathToBasicAuth.empty()) {
string foundPrefix;
string foundValue;
std::vector<std::pair<std::string, std::string>>::iterator i = _pathToBasicAuth.begin();
for (; i != _pathToBasicAuth.end(); ++i) {
string& f = i->first;
if (l.find(f) == 0) {
// f is prefix of l
if (f.length() > foundPrefix.length()) {
foundPrefix = f;
foundValue = i->second;
}
}
}
if (! foundValue.empty()) {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("Authorization: Basic "));
_writeBuffer.appendText(foundValue);
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("\r\n"));
}
}
for (auto const& header : headers) {
_writeBuffer.appendText(header.first);
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR(": "));
_writeBuffer.appendText(header.second);
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("\r\n"));
}
if (method != HttpRequest::HTTP_REQUEST_GET) {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("Content-Length: "));
_writeBuffer.appendInteger(bodyLength);
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("\r\n\r\n"));
}
else {
_writeBuffer.appendText(TRI_CHAR_LENGTH_PAIR("\r\n"));
}
if (body != nullptr) {
_writeBuffer.appendText(body, bodyLength);
}
LOG_TRACE("Request: %s", _writeBuffer.c_str());
if (_state == DEAD) {
_connection->resetNumConnectRetries();
}
// close connection to reset all read and write buffers
if (_state != FINISHED) {
this->close();
}
// we are connected, start with writing
if (_connection->isConnected()) {
_state = IN_WRITE;
_written = 0;
}
// connect to server
else {
_state = IN_CONNECT;
}
TRI_ASSERT(_state == IN_CONNECT || _state == IN_WRITE);
}
// -----------------------------------------------------------------------------
// private methods
// -----------------------------------------------------------------------------
void SimpleHttpClient::processHeader () {
TRI_ASSERT(_readBufferOffset <= _readBuffer.length());
size_t remain = _readBuffer.length() - _readBufferOffset;
char const* ptr = _readBuffer.c_str() + _readBufferOffset;
char const* pos = static_cast<char const*>(memchr(ptr, '\n', remain));
// We enforce the following invariants:
// ptr = _readBuffer.c_str() + _readBufferOffset
// _readBuffer.length() >= _readBufferOffset
// remain = _readBuffer.length() - _readBufferOffset
while (pos) {
TRI_ASSERT(_readBufferOffset <= _readBuffer.length());
TRI_ASSERT(ptr == _readBuffer.c_str() + _readBufferOffset);
TRI_ASSERT(remain == _readBuffer.length() - _readBufferOffset);
if (pos > ptr && *(pos - 1) == '\r') {
// adjust eol position
--pos;
}
// end of header found
if (*ptr == '\r' || *ptr == '\0') {
size_t len = pos - ptr;
_readBufferOffset += len + 1;
ptr += len + 1;
remain -= len + 1;
if (*pos == '\r') {
// adjust offset if line ended with \r\n
++_readBufferOffset;
ptr++;
remain--;
}
// handle chunks
if (_result->isChunked()) {
_state = IN_READ_CHUNKED_HEADER;
processChunkedHeader();
return;
}
// no content-length header in response
else if (! _result->hasContentLength()) {
_state = IN_READ_BODY;
processBody();
return;
}
// no body
else if (_result->hasContentLength() && _result->getContentLength() == 0) {
_result->setResultType(SimpleHttpResult::COMPLETE);
_state = FINISHED;
if (! _keepAlive) {
_connection->disconnect();
}
return;
}
// found content-length header in response
else if (_result->hasContentLength() && _result->getContentLength() > 0) {
if (_result->getContentLength() > _maxPacketSize) {
setErrorMessage("Content-Length > max packet size found", true);
// reset connection
this->close();
_state = DEAD;
return;
}
_state = IN_READ_BODY;
processBody();
return;
}
else {
TRI_ASSERT(false);
}
break;
}
// we have found more header fields
else {
size_t len = pos - ptr;
_result->addHeaderField(ptr, len);
if (*pos == '\r') {
// adjust length if line ended with \r\n
// (header was already added so no harm is done)
++len;
}
ptr += len + 1;
_readBufferOffset += len + 1;
remain -= (len + 1);
TRI_ASSERT(_readBufferOffset <= _readBuffer.length());
TRI_ASSERT(ptr == _readBuffer.c_str() + _readBufferOffset);
TRI_ASSERT(remain == _readBuffer.length() - _readBufferOffset);
pos = static_cast<char const*>(memchr(ptr, '\n', remain));
if (pos == nullptr) {
_readBufferOffset++;
ptr++;
remain--;
}
}
}
}
void SimpleHttpClient::processBody () {
// HEAD requests may be responded to without a body...
if (_method == HttpRequest::HTTP_REQUEST_HEAD) {
_result->setResultType(SimpleHttpResult::COMPLETE);
_state = FINISHED;
if (! _keepAlive) {
_connection->disconnect();
}
return;
}
// we need to wait for a close, if content length is unknown
if (! _result->hasContentLength()) {
return;
}
// we need to wait for more data
if (_readBuffer.length() - _readBufferOffset < _result->getContentLength()) {
return;
}
// body is compressed using deflate. inflate it
if (_result->isDeflated()) {
_readBuffer.inflate(_result->getBody(), 16384, _readBufferOffset);
}
// body is not compressed
else {
// Note that if we are here, then
// _result->getContentLength() <= _readBuffer.length()-_readBufferOffset
_result->getBody().appendText(_readBuffer.c_str() + _readBufferOffset,
_result->getContentLength());
}
_readBufferOffset += _result->getContentLength();
_result->setResultType(SimpleHttpResult::COMPLETE);
_state = FINISHED;
if (! _keepAlive) {
_connection->disconnect();
}
}
void SimpleHttpClient::processChunkedHeader () {
size_t remain = _readBuffer.length() - _readBufferOffset;
char const* ptr = _readBuffer.c_str() + _readBufferOffset;
char const* pos = static_cast<char const*>(memchr(ptr, '\n', remain));
// not yet finished, newline is missing
if (pos == nullptr) {
return;
}
// adjust eol position
if (pos > ptr && *(pos - 1) == '\r') {
--pos;
}
size_t len = pos - (_readBuffer.c_str() + _readBufferOffset);
string line(_readBuffer.c_str() + _readBufferOffset, len);
StringUtils::trimInPlace(line);
_readBufferOffset += (len + 1);
// adjust offset if line ended with \r\n
if (*pos == '\r') {
++_readBufferOffset;
++len;
}
// empty lines are an error
if (line[0] == '\r' || line.empty()) {
setErrorMessage("found invalid content-length", true);
// reset connection
this->close();
_state = DEAD;
return;
}
uint32_t contentLength;
try {
contentLength = static_cast<uint32_t>(std::stol(line, nullptr, 16)); // C++11
}
catch (...) {
setErrorMessage("found invalid content-length", true);
// reset connection
this->close();
_state = DEAD;
return;
}
// failed: too many bytes
if (contentLength > _maxPacketSize) {
setErrorMessage("Content-Length > max packet size found!", true);
// reset connection
this->close();
_state = DEAD;
return;
}
_state = IN_READ_CHUNKED_BODY;
_nextChunkedSize = contentLength;
processChunkedBody();
}
void SimpleHttpClient::processChunkedBody () {
// HEAD requests may be responded to without a body...
if (_method == HttpRequest::HTTP_REQUEST_HEAD) {
_result->setResultType(SimpleHttpResult::COMPLETE);
_state = FINISHED;
if (! _keepAlive) {
_connection->disconnect();
}
return;
}
if (_readBuffer.length() - _readBufferOffset >= _nextChunkedSize + 2) {
// last chunk length was 0, therefore we are finished
if (_nextChunkedSize == 0) {
_result->setResultType(SimpleHttpResult::COMPLETE);
_state = FINISHED;
if (! _keepAlive) {
_connection->disconnect();
}
return;
}
if (_result->isDeflated()) {
_readBuffer.inflate(_result->getBody(), 16384, _readBufferOffset);
}
else {
_result->getBody().appendText(_readBuffer.c_str() + _readBufferOffset,
(size_t) _nextChunkedSize);
}
_readBufferOffset += (size_t) _nextChunkedSize + 2;
_state = IN_READ_CHUNKED_HEADER;
processChunkedHeader();
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief extract an error message from a response
////////////////////////////////////////////////////////////////////////////////
std::string SimpleHttpClient::getHttpErrorMessage (SimpleHttpResult* result) {
triagens::basics::StringBuffer const& body = result->getBody();
std::string details;
std::unique_ptr<TRI_json_t> json(triagens::basics::JsonHelper::fromString(body.c_str(), body.length()));
if (json != nullptr) {
std::string const errorMessage = triagens::basics::JsonHelper::getStringValue(json.get(), "errorMessage", "");
int errorNum = triagens::basics::JsonHelper::getNumericValue<int>(json.get(), "errorNum", 0);
if (errorMessage != "" && errorNum > 0) {
details = ": ArangoError " + StringUtils::itoa(errorNum) + ": " + errorMessage;
}
}
return "got error from server: HTTP " +
triagens::basics::StringUtils::itoa(result->getHttpReturnCode()) +
" (" + result->getHttpReturnMessage() + ")" +
details;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief fetch the version from the server
////////////////////////////////////////////////////////////////////////////////
std::string SimpleHttpClient::getServerVersion () {
std::unique_ptr<SimpleHttpResult> response(request(HttpRequest::HTTP_REQUEST_GET,
"/_api/version",
nullptr,
0));
if (response == nullptr || ! response->isComplete()) {
return "";
}
std::string version;
if (response->getHttpReturnCode() == HttpResponse::OK) {
// default value
version = "arango";
// convert response body to json
std::unique_ptr<TRI_json_t> json(TRI_JsonString(TRI_UNKNOWN_MEM_ZONE, response->getBody().c_str()));
if (json != nullptr) {
// look up "server" value
std::string const server = triagens::basics::JsonHelper::getStringValue(json.get(), "server", "");
// "server" value is a string and content is "arango"
if (server == "arango") {
// look up "version" value
version = triagens::basics::JsonHelper::getStringValue(json.get(), "version", "");
}
}
}
else {
if (response->wasHttpError()) {
setErrorMessage(getHttpErrorMessage(response.get()), false);
}
_connection->disconnect();
}
return version;
}
}
}
// -----------------------------------------------------------------------------
// --SECTION-- END-OF-FILE
// -----------------------------------------------------------------------------
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// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @page\\|// --SECTION--\\|/// @\\}"
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