Files
MaxScale/maxutils/maxbase/include/maxbase/http.hh
Johan Wikman 910777efbc MXS-2208 Address review comments
Also report errors in more detailed manner.
2018-12-18 15:16:45 +02:00

309 lines
7.6 KiB
C++

/*
* Copyright (c) 2018 MariaDB Corporation Ab
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
*
* Change Date: 2022-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2 or later of the General
* Public License.
*/
#pragma once
#include <maxbase/ccdefs.hh>
#include <map>
#include <memory>
#include <string>
#include <vector>
namespace maxbase
{
namespace http
{
/**
* Initialize the http library.
*
* @return True if successful, false otherwise.
*/
bool init();
/**
* Finalize the http library.
*/
void finish();
/**
* RAII class for initializing the http functionality.
*/
class Init
{
public:
Init()
{
if (!mxb::http::init())
{
throw std::runtime_error("Could not initialize mxb::http.");
}
}
~Init()
{
mxb::http::finish();
}
};
enum
{
DEFAULT_CONNECT_TIMEOUT = 10, // @see https://curl.haxx.se/libcurl/c/CURLOPT_CONNECTTIMEOUT.html
DEFAULT_TIMEOUT = 10 // @see https://curl.haxx.se/libcurl/c/CURLOPT_TIMEOUT.html
};
struct Config
{
int connect_timeout_s = DEFAULT_CONNECT_TIMEOUT;
int timeout_s = DEFAULT_TIMEOUT;
};
struct Result
{
enum
{
ERROR = -1, // Some non-specific error occurred.
COULDNT_RESOLVE_HOST = -2, // The specified host cold not be resolved.
OPERATION_TIMEDOUT = -3 // The operation timed out.
};
int code = 0; // HTTP response code
std::string body; // Response body
std::map<std::string, std::string> headers; // Headers attached to the response
};
/**
* Do a HTTP GET, when no user/password is required.
*
* @param url The URL to GET.
* @param config The config to use.
*
* @note The @c url is assumed to be escaped in case it contain arguments
* that must be escaped.
*
* @return A @c Result.
*/
Result get(const std::string& url, const Config& config = Config());
/**
* Do a HTTP GET
*
* @param url The URL to GET.
* @param user Username to use.
* @param password Password for the user.
* @param config The config to use.
*
* @note The @c url is assumed to be escaped in case it contain arguments
* that must be escaped, but @c user and @c pass will always be escaped.
*
* @return A @c Result.
*/
Result get(const std::string& url,
const std::string& user, const std::string& password,
const Config& config = Config());
/**
* Do a HTTP GET, when no user/password is required.
*
* @param urls The URLs to GET.
* @param config The config to use.
*
* @note The @c urls are assumed to be escaped in case they contain arguments
* that must be escaped.
*
* @return A @c Result.
*/
std::vector<Result> get(const std::vector<std::string>& urls,
const Config& config = Config());
/**
* Do a HTTP GET
*
* @param urls The URLs to GET.
* @param user Username to use.
* @param password Password for the user.
* @param config The config to use.
*
* @note The @c urls are assumed to be escaped in case they contain arguments
* that must be escaped, but @c user and @c pass will always be escaped.
*
* @return Vector of @c Results, as many as there were @c urls.
*/
std::vector<Result> get(const std::vector<std::string>& urls,
const std::string& user, const std::string& password,
const Config& config = Config());
/**
* @class mxb::http::Async
*
* Class for performing multiple HTTP GETs concurrently and asynchronously.
* The instance should be viewed as a handle to the operation. If it is
* copied, both instances refer to the same operation and both instances
* can be used for driving the GET. However, an instance can *only* be
* used or copied in the thread where it is created.
*/
class Async
{
public:
enum status_t
{
READY, // The result is ready.
ERROR, // The operation has failed.
PENDING // The operation is pending.
};
class Imp
{
public:
virtual ~Imp();
virtual status_t status() const = 0;
virtual status_t perform(long timeout_ms) = 0;
virtual long wait_no_more_than() const = 0;
virtual const std::vector<Result>& results() const = 0;
};
/**
* Defalt constructor creates an asynchronous operation whose status is ERROR.
*/
Async();
/**
* Copy constructor; creates an instance that refers to the same operation
* the argument refers to.
*
* @param rhs An existing @c Async instance.
*/
Async(const Async& rhs)
: m_sImp(rhs.m_sImp)
{
}
/**
* Assigns an asynchronous operation.
*
* @param rhs An other @c Async instance.
*
* @return *this.
*/
Async& operator = (const Async& rhs)
{
std::shared_ptr<Imp> sImp(rhs.m_sImp);
m_sImp.swap(sImp);
return *this;
}
/**
* Return the status of the operation.
*
* @return @c READY|ERROR|PENDING
*/
status_t status() const
{
return m_sImp->status();
}
/**
* Performs a step in the operation.
*
* @param timeout_ms The maximum timeout for waiting for activity on the
* underlying socket descriptors.
*
* @return @c READY|ERROR|PENDING
*/
status_t perform(long timeout_ms = 0)
{
return m_sImp->perform(timeout_ms);
}
/**
* How much time to wait at most, before calling perform() again.
*
* This value is dependent upon the timeouts that were specified when
* the operation was initiated. To ensure that operations are not timed
* out, do not wait as long as this function returns but significantly
* less.
*
* @return Maximum time to wait in milliseconds.
*/
long wait_no_more_than() const
{
return m_sImp->wait_no_more_than();
}
/**
* The result of each operation. This function should not be called
* before the status is READY.
*
* @return Vector of results.
*/
const std::vector<Result>& results() const
{
return m_sImp->results();
}
public:
Async(const std::shared_ptr<Imp>& sImp)
: m_sImp(sImp)
{
}
private:
std::shared_ptr<Imp> m_sImp;
};
/**
* Return human-readable string for a status value.
*
* @param status A status value.
*
* @return The corresponding string.
*/
const char* to_string(Async::status_t status);
/**
* Do a HTTP GET, asynchronously.
*
* @param urls The URLs to GET.
* @param config The config to use.
*
* @note The @c urls are assumed to be escaped in case they contain arguments
* that must be escaped.
*
* @return An Async instance using which the operation can be performed.
*/
Async get_async(const std::vector<std::string>& urls,
const Config& config = Config());
/**
* Do a HTTP GET, asynchronously.
*
* @param urls The URLs to GET.
* @param user Username to use.
* @param password Password for the user.
* @param config The config to use.
*
* @note The @c urls are assumed to be escaped in case they contains arguments
* that must be escaped, but @c user and @c pass will always be escaped.
*
* @return An Async instance using which the operation can be performed.
*/
Async get_async(const std::vector<std::string>& urls,
const std::string& user, const std::string& password,
const Config& config = Config());
}
}