redis_command.hpp

浏览该文件的文档.

#pragma once
#include "../acl_cpp_define.hpp"
#include "../stdlib/noncopyable.hpp"
#include "../stdlib/tbox.hpp"
#include <map>
#include <list>
#include <vector>
#include "redis_result.hpp"

#if !defined(ACL_CLIENT_ONLY) && !defined(ACL_REDIS_DISABLE)

namespace acl
{

class redis_request;
class redis_client;
class redis_client_cluster;
class redis_client_pipeline;
class redis_pipeline_message;

/**
 * redis 客户端命令类的纯虚父类;
 * the redis command classes's base virtual class, which includes the basic
 * functions for all sub-classes
 */
class ACL_CPP_API redis_command : public noncopyable
{
public:
        /**
         * 缺省的构造函数，如果使用此构造函数初始化类对象，则必须调用
         * set_client 或 set_cluster 设置 redis 客户端命令类对象的通讯方式。
         * default constructor. You must set the communication method by
         * set_client or set_cluster functions.
         */
        redis_command(void);

        /**
         * 当使用非集群模式时，可以使用此构造函数设置 redis 通信对象。
         * Using this constructor to set the redis communication mode,
         * usually in no-cluster mode.
         * @param conn {redis_client*} redis 通信类对象
         *  the redis communication in no-cluster mode
         */
        redis_command(redis_client* conn);

        /**
         * 集群模式的构造函数，在构造类对象时指定了集群模式的
         * redis_client_cluster 对象。
         * Using this constructor to set the redis_client_cluster, usually in
         * cluster mode.
         * @param cluster {redis_client_cluster*} redis 集群连接对象
         *  redis cluster object in cluster mode
         *  the max of every connection pool with all the redis nodes,
         *  if be set 0, then there is no connections limit in
         *  connections pool.
         */
        redis_command(redis_client_cluster* cluster);

        ACL_CPP_DEPRECATED
        redis_command(redis_client_cluster* cluster, size_t max_conns);

        redis_command(redis_client_pipeline* pipeline);

        virtual ~redis_command(void);

        /**
         * 在进行每个命令处理前，是否要求检查 socket 句柄与地址的匹配情况，当
         * 打开该选项时，将会严格检查匹配情况，但会影响一定性能，因此该设置仅
         * 用在 DEBUG 时的运行场景
         * @param on {bool}
         */
        void set_check_addr(bool on);

        /**
         * 在重复使用一个继承于 redis_command 的子类操作 redis 时，需要在
         * 下一次调用前调用本方法以释放上次操作的临时对象;
         * when reusing a redis command sub-class, the reset method should be
         * called first to rlease some resources in last command operation
         * @param save_slot {bool} 当采用集群模式时，该参数决定是否需要重新
         *  计算哈希槽值，如果反复调用 redis 命令过程中的 key 值不变，则可以保
         *  留此哈希槽值以减少内部重新进行计算的次数;
         *  when in cluster mode, if your operations is on the same key, you
         *  can set the param save_slot to false which can reduse the times
         *  of compute the same key's hash-slot.
         */
        void clear(bool save_slot = false);

        ACL_CPP_DEPRECATED_FOR("clear")
        void reset(bool save_slot = false);

        /**
         * 在使用非集群方式时，通过本函数将从连接池获得的连接对象;
         * when not using cluster mode, the function is used
         * to set the connection for next redis command operation.
         * @param conn {redis_client*} 与 redis 客户端命令进行关联;
         *  the redis connection to be set in next redis operation
         */
        void set_client(redis_client* conn);

        /**
         * 获得当前 redis 客户端命令的连接对象;
         * get redis connection set by set_client function
         * @return {redis_client*} 返回 NULL 表示没有连接对象与当前的命令对象
         *  进行绑定;
         *  the internal redis connection be returned, NULL if no redis
         *  connection be set 
         */
        redis_client* get_client(void) const
        {
                return conn_;
        }

        /**
         * 获得当前 redis 命令对象所绑定的服务器地址，只有当该对象与 redis_client
         * 绑定时（即调用 set_client) 才可以调用本函数
         * get the redis-server's addr used by the current command. this
         * method can only be used only if the redis_client was set by
         * set_client method.
         * @return {const char*} 返回空串 "" 表示没有绑定 redis 连接对象
         *  if "" was resturned, the redis connection was not set
         */
        const char* get_client_addr(void) const;

        /**
         * 设置连接池集群管理器;
         * set the redis cluster object in redis cluster mode
         * @param cluster {redis_client_cluster*} redis 集群连接对象;
         *  the redis_cluster connection object which can connect to any
         *  redis-server and support connection pool
         *  when dynamicly creating connection pool to any redis-server, use
         *  this param to limit the max number for each connection pool
         */
        void set_cluster(redis_client_cluster* cluster);

        ACL_CPP_DEPRECATED
        void set_cluster(redis_client_cluster* cluster, size_t max_conns);

        /**
         * 获得所设置的连接池集群管理器;
         * get redis_cluster object set by set_cluster function
         * @return {redis_client_cluster*}
         */
        redis_client_cluster* get_cluster(void) const
        {
                return cluster_;
        }

        /**
         * 设置pipeline通信对象，使用pipeline模式
         * set the redis communication in pipeline mode
         * @param pipeline {redis_client_pipeline*} pipeline communication object
         * @param use_mbox {bool} if using acl::mbox to get the result,
         *  acl::tbox will be used if use_mbox is set to false; acl::mbox
         *  will be used as default internal.
         */
        void set_pipeline(redis_client_pipeline* pipeline, bool use_mbox = true);

        /**
         * get the redis pipeline communication object been set before
         * @return {redis_client_pipeline*} return NULL if not set
         */
        redis_client_pipeline* get_pipeline(void) const
        {
                return pipeline_;
        }

        /**
         * 获得内存池句柄，该内存池由 redis_command 内部产生;
         * get memory pool handle been set
         * @return {dbuf_pool*}
         */
        dbuf_pool* get_dbuf(void) const
        {
                return dbuf_;
        }

        /**
         * 获得当前结果结点的数据类型;
         * get the result type returned from redis-server
         * @return {redis_result_t}
         */
        redis_result_t result_type(void) const;

        /**
         * 当返回值为 REDIS_RESULT_STATUS 类型时，本方法返回状态信息;
         * when result type is REDIS_RESULT_STATUS, the status info can be
         * get by this function
         * @return {const char*} 返回 "" 表示出错;
         *  "" will be returned on error
         */
        const char* result_status(void) const;

        /**
         * 当出错时返回值为 REDIS_RESULT_ERROR 类型，本方法返回出错信息;
         * when result type is REDIS_RESULT_ERROR, the error info can be
         * get by this function
         * @return {const char*} 返回空串 "" 表示没有出错信息;
         *  "" will be returned when no error info
         */
        const char* result_error(void) const;

        /**
         * 获得当前结果结点存储的对象的个数, 该方法可以获得结果为下面两个方法
         * (result_child/result_value) 所需要的数组元素的个数;
         * get number of result objects, just for functions
         * result_child/result_value 
         * @return {size_t} 返回值与存储类型的对应关系如下：
         *  the relation between return value and result type, as below:
         *  REDIS_RESULT_ERROR: 1
         *  REDIS_RESULT_STATUS: 1
         *  REDIS_RESULT_INTEGER: 1
         *  REDIS_RESULT_STRING: > 0 时表示该字符串数据被切分成非连接内存块的个数;
         *       when the result type is REDIS_RESULT_STRING and the the
         *       string is too large, the string was be cut into many small
         *       chunks, the returned value is the chunks number
         *  REDIS_RESULT_ARRAY: children_->size()
         */
        size_t result_size(void) const;

        /**
         * 当返回值为 REDIS_RESULT_INTEGER 类型时，本方法返回对应的 32 位整数值;
         * get 32-bits number value if result type is REDIS_RESULT_INTERGER
         * @param success {bool*} 本指针非 NULL 时记录操作过程是否成功;
         *  if the param pointer is not NULL, which will save status of
         *  success or not for result from redis-server
         * @return {int}
         */
        int result_number(bool* success = NULL) const;

        /**
         * 当返回值为 REDIS_RESULT_INTEGER 类型时，本方法返回对应的 64 位整数值;
         * get 64-bits number value if result type is REDIS_RESULT_INTERGER
         * @param success {bool*} 本指针非 NULL 时记录操作过程是否成功;
         *  if the param pointer is not NULL, which will save status of
         *  success or not for result from redis-server
         * @return {long long int}
         */
        long long int result_number64(bool* success = NULL) const;

        /**
         * 返回对应下标的数据(当数据类型非 REDIS_RESULT_ARRAY 时）;
         * get string result when result type isn't REDIS_RESULT_ARRAY
         * @param i {size_t} 数组下标;
         *  the array index
         * @param len {size_t*} 当为非 NULL 指针时存储所返回数据的长度;
         *  *len will save the result's length if len is not NULL
         * @return {const char*} 返回 NULL 表示下标越界;
         *  NULL will return if i beyonds the array's size
         */
        const char* get_result(size_t i, size_t* len = NULL) const;

        /**
         * 判断当前所绑定的 redis 连接流对象(redis_client) 连接是否已经关闭；
         * 只有内部的 conn_ 流对象非空时调用此函数才有意义;
         * to judge if the redis connection was be closed, only redis_client
         * object be set internal
         * @return {bool}
         */
        bool eof(void) const;

        /**
         * 获得本次 redis 操作过程的结果;
         * get result object of last redis operation
         * @return {redis_result*}
         */
        const redis_result* get_result(void) const;

        /**
         * 当查询结果为数组对象时调用本方法获得一个数组元素对象;
         * get one result ojbect of array if result type is REDIS_RESULT_ARRAY
         * @param i {size_t} 数组对象的下标值;
         *  the result array's index
         * @return {const redis_result*} 当结果非数组对象或结果为空或出错时
         *  该方法返回 NULL;
         *  NULL will be resturned when result is not REDIS_RESULT_ARRAY or
         *  array empty or error
         */
        const redis_result* result_child(size_t i) const;

        /**
         * 当从 redis-server 获得的数据是一组字符串类型的结果集时，可以调用
         * 本函数获得某个指定下标位置的数据;
         * when the reply from redis-serveer are strings array, this
         * function can be used to get the string specified by a subscript
         * @param i {size_t} 下标（从 0 开始）
         *  the subscript of strings array
         * @param len {size_t*} 若该指针非空，则存储所返回结果的长度（仅当该
         *  方法返回非空指针时有效）
         *  if len not a NULL pointer, it will store the length of string
         *  specified by the subscript
         * @return {const char*} 返回对应下标的值，当返回 NULL 时表示该下标没
         *  有值，为了保证使用上的安全性，返回的数据总能保证最后是以 \0 结尾，
         *  在计算数据长度时不包含该结尾符，但为了兼容二进制情形，调用者还是
         *  应该通过返回的 len 存放的长度值来获得数据的真实长度
         *  the string will be returned associate with the subscript, if there
         *  are nothing with the subscript, NULL will be returned
         */
        const char* result_value(size_t i, size_t* len = NULL) const;

        /////////////////////////////////////////////////////////////////////
        /**
         * 设置是否对请求数据进行分片处理，如果为 true 则内部在组装请求协议的
         * 时候不会将所有数据块重新组装成一个连续的大数据块
         * just for request package, setting flag for sending data with
         * multi data chunks; this is useful when the request data is large
         * @param on {bool} 内部默认值为 false
         *  if true the request data will not be combined one package,
         *  internal default is false
         */
        void set_slice_request(bool on);

        /**
         * 设置是否对响应数据进行分片处理，如果为 true 则当服务器的返回数据
         * 比较大时则将数据进行分片，分成一些不连续的数据块
         * just for response package, settint flag for receiving data
         * if split the large response data into multi little chunks
         * @param on {bool} 内部默认值为 false
         *  if true the response data will be splitted into multi little
         *  data, which is useful for large reponse data for avoiding
         *  malloc large continuously memory from system.
         *  internal default is false
         */
        void set_slice_respond(bool on);

public:
        /**
         * 直接组合 redis 协议命令方式，从 redis 服务器获得结果
         * @param argc {size_t} 后面数组中数组元素个数
         * @param argv {const char*[]} redis 命令组成的数组
         * @param lens {size_t[]} argv 中数组元素的长度
         * @param nchild {size_t} 有的 redis 命令需要获取多个结果集，如：subop
         * @return {const redis_result*} 返回的结果集
         */
        const redis_result* request(size_t argc, const char* argv[],
                size_t lens[], size_t nchild = 0);

        /**
         * 直接组合 redis 协议命令方式，从 redis 服务器获得结果
         * @param args {const std::vector<string>&} redis 命令组成的数组
         * @param nchild {size_t} 有的 redis 命令需要获取多个结果集，如：subop
         * @return {const redis_result*} 返回的结果集
         */
        const redis_result* request(const std::vector<string>& args,
                size_t nchild = 0);

        const string* request_buf(void) const
        {
                return request_buf_;
        }

        /**
         * 根据请求命令字列表创建 redis 请求协议数据
         * @param argc {size_t} 命令参数个数
         * @param argv {const char* []} 命令参数数组
         * @param lens {size_t []} 每个命令参数长度数组
         * @param out {string&} 存放创建结果
         */
        static void build_request(size_t argc, const char* argv[],
                size_t lens[], string& out);

        /**
         * 根据命令字列表创建 redis 请求协议并存储于 redis_command 中，以备在请求时使用
         * @param argc {size_t} 命令参数个数
         * @param argv {const char* []} 命令参数数组
         * @param lens {size_t []} 每个命令参数长度数组
         */
        void build_request(size_t argc, const char* argv[], size_t lens[]);

protected:
        const redis_result* run(size_t nchild = 0, int* timeout = NULL);

        void clear_request(void);
        const redis_result** scan_keys(const char* cmd, const char* key,
                int& cursor, size_t& size, const char* pattern,
                const size_t* count);
        const redis_result** scan_keys(const char* cmd, const char* key,
                size_t klen, int& cursor, size_t& size, const char* pattern,
                const size_t* count);

        /*******************************************************************/

        void build(const char* cmd, const char* key,
                const std::map<string, string>& attrs);
        void build(const char* cmd, const char* key, size_t klen,
                const std::map<string, string>& attrs);
        void build(const char* cmd, const char* key,
                const std::map<string, const char*>& attrs);

        void build(const char* cmd, const char* key,
                const std::vector<string>& names,
                const std::vector<string>& values);
        void build(const char* cmd, const char* key, size_t klen,
                const std::vector<string>& names,
                const std::vector<string>& values);
        void build(const char* cmd, const char* key,
                const std::vector<const char*>& names,
                const std::vector<const char*>& values);

        void build(const char* cmd, const char* key,
                const char* names[], const char* values[], size_t argc);
        void build(const char* cmd, const char* key,
                const int names[], const char* values[], size_t argc);
        void build(const char* cmd, const char* key,
                const char* names[], const size_t names_len[],
                const char* values[], const size_t values_len[], size_t argc);
        void build(const char* cmd, const char* key, size_t klen,
                const char* names[], const size_t names_len[],
                const char* values[], const size_t values_len[], size_t argc);

        /*******************************************************************/

        void build(const char* cmd, const char* key,
                const std::vector<string>& names);
        void build(const char* cmd, const char* key, size_t klen,
                const std::vector<string>& names);
        void build(const char* cmd, const char* key,
                const std::vector<const char*>& names);
        void build(const char* cmd, const char* key,
                const std::vector<int>& names);

        void build(const char* cmd, const char* key,
                const char* names[], size_t argc);
        void build(const char* cmd, const char* key,
                const char* names[], const size_t lens[], size_t argc);
        void build(const char* cmd, const char* key, size_t klen,
                const char* names[], const size_t lens[], size_t argc);
        void build(const char* cmd, const char* key,
                const int names[], size_t argc);

        /*******************************************************************/

protected:
        int get_number(bool* success = NULL);
        long long int get_number64(bool* success = NULL);
        int get_number(std::vector<int>& out);
        int get_number64(std::vector<long long int>& out);
        bool check_status(const char* success = "OK");

        int get_status(std::vector<bool>& out);
        const char* get_status(void);

        int get_string(string& buf);
        int get_string(string* buf);
        int get_string(char* buf, size_t size);
        int get_strings(std::vector<string>& result);
        int get_strings(std::vector<string>* result);
        int get_strings(std::list<string>& result);
        int get_strings(std::list<string>* result);
        int get_strings(std::map<string, string>& result);
        int get_strings(std::vector<string>& names,
                std::vector<string>& values);
        int get_strings(std::vector<const char*>& names,
                std::vector<const char*>& values);

        /************************** common *********************************/
protected:
        dbuf_pool* dbuf_;

private:
        void init(void);

public:
        // compute hash slot of the given key and store it in the current
        // redis command will be used in the next operation for redis cluster.
        void hash_slot(const char* key);
        void hash_slot(const char* key, size_t len);

        // get the current hash slot stored internal
        int get_slot(void) const {
                return slot_;
        }

        bool is_check_addr(void) const {
                return check_addr_;
        }

protected:
        bool check_addr_;
        char addr_[32];
        redis_client* conn_;
        redis_client_cluster* cluster_;
        redis_client_pipeline* pipeline_;
        bool pipe_use_mbox_;
        int  slot_;
        int  redirect_max_;
        int  redirect_sleep_;

public:
        const char* get_addr(const char* info);
        void set_client_addr(const char* addr);
        void set_client_addr(redis_client& conn);

public:
        redis_request* get_request_obj(void) const {
                return request_obj_;
        }

        string* get_request_buf(void) const {
                return request_buf_;
        }

        bool is_slice_req(void) const {
                return slice_req_;
        }

        // get pipeline message bound with the current command
        redis_pipeline_message& get_pipeline_message(void);

protected:
        /************************** request ********************************/
        bool slice_req_;
        string* request_buf_;
        redis_request* request_obj_;
        size_t  argv_size_;
        const char**  argv_;
        size_t* argv_lens_;
        size_t  argc_;

        // reserve the argv space with the specified value at least
        void argv_space(size_t n);

        // build request in one request buffer
        void build_request1(size_t argc, const char* argv[], size_t lens[]);

        // build request with slice request obj
        void build_request2(size_t argc, const char* argv[], size_t lens[]);

protected:
        /************************** respond ********************************/
        bool slice_res_;
        redis_pipeline_message* pipe_msg_;
        const redis_result* result_;

        // save the error info into log
        void logger_result(const redis_result* result);
};

} // namespace acl

#endif // !defined(ACL_CLIENT_ONLY) && !defined(ACL_REDIS_DISABLE)