Develop merge

Develop merge

server/modules/routing/readwritesplit/rwsplitsession.hh

@@ -0,0 +1,148 @@
+#pragma once
+/*
+ * Copyright (c) 2016 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: 2020-01-01
+ *
+ * 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.
+ */
+
+#include "readwritesplit.hh"
+#include "rwsplit_ps.hh"
+
+
+/** Enum for tracking client reply state */
+enum reply_state_t
+{
+    REPLY_STATE_START,          /**< Query sent to backend */
+    REPLY_STATE_DONE,           /**< Complete reply received */
+    REPLY_STATE_RSET_COLDEF,    /**< Resultset response, waiting for column definitions */
+    REPLY_STATE_RSET_ROWS       /**< Resultset response, waiting for rows */
+};
+
+/** Reply state change debug logging */
+#define LOG_RS(a, b) MXS_DEBUG("%s %s -> %s", (a)->uri(), \
+    rstostr((a)->get_reply_state()), rstostr(b));
+
+typedef std::map<uint32_t, uint32_t> BackendHandleMap; /** Internal ID to external ID */
+typedef std::map<uint32_t, uint32_t> ClientHandleMap;  /** External ID to internal ID */
+
+class RWBackend: public mxs::Backend
+{
+    RWBackend(const RWBackend&);
+    RWBackend& operator=(const RWBackend&);
+
+public:
+    RWBackend(SERVER_REF* ref);
+    ~RWBackend();
+
+    reply_state_t get_reply_state() const;
+    void set_reply_state(reply_state_t state);
+
+    void add_ps_handle(uint32_t id, uint32_t handle);
+    uint32_t get_ps_handle(uint32_t id) const;
+
+    bool execute_session_command();
+    bool write(GWBUF* buffer, response_type type = EXPECT_RESPONSE);
+
+private:
+    reply_state_t    m_reply_state;
+    BackendHandleMap m_ps_handles; /**< Internal ID to backend PS handle mapping */
+};
+
+typedef std::tr1::shared_ptr<RWBackend> SRWBackend;
+typedef std::list<SRWBackend> SRWBackendList;
+
+typedef std::tr1::unordered_set<std::string> TableSet;
+typedef std::map<uint64_t, uint8_t>          ResponseMap;
+
+/** Map of COM_STMT_EXECUTE targets by internal ID */
+typedef std::tr1::unordered_map<uint32_t, SRWBackend> ExecMap;
+
+/**
+ * The client session of a RWSplit instance
+ */
+class RWSplitSession
+{
+    RWSplitSession(const RWSplitSession&);
+    RWSplitSession& operator=(const RWSplitSession&);
+
+public:
+    RWSplitSession(const Config& config);
+
+    // TODO: Make member variables private
+    skygw_chk_t             rses_chk_top;
+    bool                    rses_closed; /**< true when closeSession is called */
+    SRWBackendList          backends; /**< List of backend servers */
+    SRWBackend              current_master; /**< Current master server */
+    SRWBackend              target_node; /**< The currently locked target node */
+    Config                  rses_config; /**< copied config info from router instance */
+    int                     rses_nbackends;
+    enum ld_state           load_data_state; /**< Current load data state */
+    bool                    have_tmp_tables;
+    uint64_t                rses_load_data_sent; /**< How much data has been sent */
+    DCB*                    client_dcb;
+    uint64_t                sescmd_count;
+    int                     expected_responses; /**< Number of expected responses to the current query */
+    GWBUF*                  query_queue; /**< Queued commands waiting to be executed */
+    RWSplit*                router; /**< The router instance */
+    TableSet                temp_tables; /**< Set of temporary tables */
+    mxs::SessionCommandList sescmd_list; /**< List of executed session commands */
+    ResponseMap             sescmd_responses; /**< Response to each session command */
+    uint64_t                sent_sescmd; /**< ID of the last sent session command*/
+    uint64_t                recv_sescmd; /**< ID of the most recently completed session command */
+    PSManager               ps_manager;  /**< Prepared statement manager*/
+    ClientHandleMap         ps_handles;  /**< Client PS handle to internal ID mapping */
+    ExecMap                 exec_map; /**< Map of COM_STMT_EXECUTE statement IDs to Backends */
+    skygw_chk_t             rses_chk_tail;
+};
+
+/** Struct for holding routing related information */
+struct RouteInfo
+{
+    RouteInfo(RWSplitSession* rses, GWBUF* buffer);
+
+    route_target_t target;  /**< Route target type, TARGET_UNDEFINED for unknown */
+    uint8_t        command; /**< The command byte, 0xff for unknown commands */
+    uint32_t       type;    /**< The query type, QUERY_TYPE_UNKNOWN for unknown types*/
+    uint32_t       stmt_id; /**< Prepared statement ID, 0 for unknown */
+};
+
+/**
+ * Helper function to convert reply_state_t to string
+ */
+static inline const char* rstostr(reply_state_t state)
+{
+    switch (state)
+    {
+    case REPLY_STATE_START:
+        return "REPLY_STATE_START";
+
+    case REPLY_STATE_DONE:
+        return "REPLY_STATE_DONE";
+
+    case REPLY_STATE_RSET_COLDEF:
+        return "REPLY_STATE_RSET_COLDEF";
+
+    case REPLY_STATE_RSET_ROWS:
+        return "REPLY_STATE_RSET_ROWS";
+    }
+
+    ss_dassert(false);
+    return "UNKNOWN";
+}
+
+/**
+ * @brief Get the internal ID for the given binary prepared statement
+ *
+ * @param rses   Router client session
+ * @param buffer Buffer containing a binary protocol statement other than COM_STMT_PREPARE
+ *
+ * @return The internal ID of the prepared statement that the buffer contents refer to
+ */
+uint32_t get_internal_ps_id(RWSplitSession* rses, GWBUF* buffer);