mongoc_client_command_simple

前言

刚开始玩MongoDB
看到mongoc_client_command_simple函数, 不太明白干嘛用的.
看了mongo-c-driver中的代码示例, 大致明白了.
mongoc_client_command_simple等于在mongo本地控制台执行一些mongo自己的数据库命令, 并返回结果.
大致将mongo源码中使用的mongoc_client_command_simple的例子试了一遍, 大概有5,6个例子

使用mongoc_client_command_simpled的API列表

mongoc_collection_command_simple
mongoc_database_command_simple
background_mongoc_client_command_simple
这几个API没有试, 用到的时候, 再试验.

测试程序

#include <stdlib.h>#include <stdio.h>#include <sys/stat.h>#include <cstddef>#include "MongoDbEx.h"int testcase_mongoc_example_command_simple(int argc, char* argv[]);int main(int argc, char* argv[]){    printf("============================================================\n");    printf(">> testcase v1.0.0.3\n");    printf("============================================================\n");    testcase_mongoc_example_command_simple(argc, argv);    printf("============================================================\n");    printf("END\n");    printf("============================================================\n");    return 0;}int testcase_mongoc_example_command_simple(int argc, char* argv[]){    mongoc_client_t* client = NULL;    mongoc_database_t* database = NULL;    mongoc_collection_t* collection = NULL;    bson_t* insert = NULL;    bson_error_t error;    bool retval = false;    mongoc_init();    client = mongoc_client_new("mongodb://localhost:27017");    /*     * Register the application name so we can track it in the profile logs     * on the server. This can also be done from the URI (see other examples).     */    mongoc_client_set_appname(client, "connect-example");    database = mongoc_client_get_database(client, "db_name");    collection = mongoc_client_get_collection(client, "db_name", "coll_name");    // cmd :  ping    retval = DbOptExec_command_simple(client, "admin", "ping", &error);    if (!retval) {        ShowErrMsg("ping", &error);        return EXIT_FAILURE;    }    /**    [ping] { "ok" : 1.0 }    */    insert = BCON_NEW("hello", BCON_UTF8("world"));    if (!mongoc_collection_insert(                collection, MONGOC_INSERT_NONE, insert, NULL, &error)) {        ShowErrMsg("mongoc_collection_insert", &error);    }    // cmd : buildinfo    bson_destroy(insert);    retval = DbOptExec_command_simple(client, "admin", "buildinfo", &error);    if (!retval) {        ShowErrMsg("buildinfo", &error);    }    /**    [buildinfo] {        "version" : "2.6.10",        "gitVersion" : "5901dbfb49d16eaef6f2c2c50fba534d23ac7f6c",        "OpenSSLVersion" : "",        "sysInfo" : "Linux build18.nj1.10gen.cc 2.6.32-431.3.1.el6.x86_64 #1 SMP Fri Jan 3 21:39:27 UTC 2014 x86_64 BOOST_LIB_VERSION=1_49",        "loaderFlags" : "-fPIC -pthread -Wl,-z,now -rdynamic",        "compilerFlags" : "-Wnon-virtual-dtor -Woverloaded-virtual -fPIC -fno-strict-aliasing -ggdb -pthread -Wall -Wsign-compare -Wno-unknown-pragmas -Winvalid-pch -pipe -Werror -O3 -Wno-unused-function -Wno-deprecated-declarations -fno-builtin-memcmp",        "allocator" : "tcmalloc",        "versionArray" : [ 2, 6, 10, 0 ],        "javascriptEngine" : "V8",        "bits" : 64,        "debug" : false,        "maxBsonObjectSize" : 16777216,        "ok" : 1.0 }    */    // cmd : serverStatus    retval = DbOptExec_command_simple(client, "admin", "serverStatus", &error);    if (!retval) {        ShowErrMsg("serverStatus", &error);    }    /**    [serverStatus]    {    "host" : "debian",    "version" : "2.6.10",    "process" : "mongod",    "pid" : 3243,    "uptime" : 21899.0,    "uptimeMillis" : 21897854,    "uptimeEstimate" : 19920.0,    "localTime" : { "$date" : 1491227764737 },    "asserts" : { "regular" : 0, "warning" : 0, "msg" : 0, "user" : 0, "rollovers" : 0 },    "backgroundFlushing" : { "flushes" : 364, "total_ms" : 54, "average_ms" : 0.14835164835164835195, "last_ms" : 0, "last_finished" : { "$date" : 1491227708337 } },    "connections" : { "current" : 1, "available" : 818, "totalCreated" : 9 },    "cursors" : { "note" : "deprecated, use server status metrics", "clientCursors_size" : 0, "totalOpen" : 0, "pinned" : 0, "totalNoTimeout" : 0, "timedOut" : 0 },    "dur" : { "commits" : 29, "journaledMB" : 0.0, "writeToDataFilesMB" : 0.0, "compression" : 0.0, "commitsInWriteLock" : 0, "earlyCommits" : 0,    "timeMs" : { "dt" : 3044, "prepLogBuffer" : 0, "writeToJournal" : 0, "writeToDataFiles" : 0, "remapPrivateView" : 0 } },    "extra_info" : { "note" : "fields vary by platform", "heap_usage_bytes" : 62725408, "page_faults" : 98 },    "globalLock" : { "totalTime" : 21897856000, "lockTime" : 5334268,    "currentQueue" : { "total" : 0, "readers" : 0, "writers" : 0 },    "activeClients" : { "total" : 0, "readers" : 0, "writers" : 0 } },    "indexCounters" : { "accesses" : 19, "hits" : 19, "misses" : 0, "resets" : 0, "missRatio" : 0.0 },    "locks" : { "." : {    "timeLockedMicros" : { "R" : 435761, "W" : 5334268 },    "timeAcquiringMicros" : { "R" : 4899977, "W" : 2994540 } },    "admin" : { "timeLockedMicros" : { "r" : 151982, "w" : 0 },    "timeAcquiringMicros" : { "r" : 369253, "w" : 0 } },    "local" : { "timeLockedMicros" : { "r" : 128739, "w" : 83 }, "timeAcquiringMicros" : { "r" : 54838, "w" : 1 } },    "testdb" : { "timeLockedMicros" : { "r" : 2081468, "w" : 130 }, "timeAcquiringMicros" : { "r" : 19698, "w" : 3 } },    "mongodb" : { "timeLockedMicros" : { "r" : 191151, "w" : 128 }, "timeAcquiringMicros" : { "r" : 30413, "w" : 4 } },    "db_name" : { "timeLockedMicros" : { "r" : 375654, "w" : 908 }, "timeAcquiringMicros" : { "r" : 14419, "w" : 40 } },    "Barca" : { "timeLockedMicros" : { "r" : 158307, "w" : 134 }, "timeAcquiringMicros" : { "r" : 19699, "w" : 3 } },    "dbs" : { "timeLockedMicros" : { "r" : 610389, "w" : 224 }, "timeAcquiringMicros" : { "r" : 17663, "w" : 6 } },    "test1" : { "timeLockedMicros" : { "r" : 829203, "w" : 28 }, "timeAcquiringMicros" : { "r" : 15951, "w" : 2 } },    "yekai" : { "timeLockedMicros" : { "r" : 2065973, "w" : 269 }, "timeAcquiringMicros" : { "r" : 61179, "w" : 4 } },    "tutorial" : { "timeLockedMicros" : { "r" : 1491259, "w" : 157 }, "timeAcquiringMicros" : { "r" : 28555, "w" : 3 } } },    "network" : { "bytesIn" : 5730, "bytesOut" : 13310, "numRequests" : 44 },    "opcounters" : { "insert" : 9, "query" : 3641, "update" : 0, "delete" : 0, "getmore" : 0, "command" : 38 },    "opcountersRepl" : { "insert" : 0, "query" : 0, "update" : 0, "delete" : 0, "getmore" : 0, "command" : 0 },    "recordStats" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0,    "Barca" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "admin" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "db_name" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "dbs" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "local" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "mongodb" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "test1" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "testdb" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "tutorial" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 },    "yekai" : { "accessesNotInMemory" : 0, "pageFaultExceptionsThrown" : 0 } },    "writeBacksQueued" : false,    "mem" : { "bits" : 64, "resident" : 158, "virtual" : 62683, "supported" : true, "mapped" : 31251, "mappedWithJournal" : 62502 },    "metrics" : { "cursor" : { "timedOut" : 0, "open" : { "noTimeout" : 0, "pinned" : 0, "total" : 0 } },    "document" : { "deleted" : 0, "inserted" : 9, "returned" : 0, "updated" : 0 },    "getLastError" : { "wtime" : { "num" : 0, "totalMillis" : 0 }, "wtimeouts" : 0 },    "operation" : { "fastmod" : 0, "idhack" : 0, "scanAndOrder" : 0 },    "queryExecutor" : { "scanned" : 0, "scannedObjects" : 0 },    "record" : { "moves" : 0 },    "repl" : {    "apply" : { "batches" : { "num" : 0, "totalMillis" : 0 }, "ops" : 0 },    "buffer" : { "count" : 0, "maxSizeBytes" : 268435456, "sizeBytes" : 0 },    "network" : { "bytes" : 0, "getmores" : { "num" : 0, "totalMillis" : 0 }, "ops" : 0, "readersCreated" : 0 },    "preload" : { "docs" : { "num" : 0, "totalMillis" : 0 }, "indexes" : { "num" : 0, "totalMillis" : 0 } } },    "storage" : { "freelist" : { "search" : { "bucketExhausted" : 0, "requests" : 8, "scanned" : 16 } } },    "ttl" : { "deletedDocuments" : 0, "passes" : 364 } },    "ok" : 1.0 }    */    // cmd : ismaster    retval = DbOptExec_command_simple(client, "admin", "ismaster", &error);    if (!retval) {        ShowErrMsg("ismaster", &error);    }    /**    [ismaster] {        "ismaster" : true,        "maxBsonObjectSize" : 16777216,        "maxMessageSizeBytes" : 48000000,        "maxWriteBatchSize" : 1000,        "localTime" : { "$date" : 1491230240360 },        "maxWireVersion" : 2,        "minWireVersion" : 0,        "ok" : 1.0        }    */    // cmd : getlasterror    retval = DbOptExec_command_simple(client, "admin", "getlasterror", &error);    if (!retval) {        ShowErrMsg("getlasterror", &error);    }    /**    [getlasterror] {        "connectionId" : 11,        "n" : 0,        "syncMillis" : 0,        "writtenTo" : null,        "err" : null,        "ok" : 1.0        }    */    // cmd : foo    retval = DbOptExec_command_simple(client, "admin", "foo", &error);    if (!retval) {        ShowErrMsg("foo", &error);    }    /**    [foo] error : no such cmd: foo    */    // cmd : empty    // 空命令会报错的//     retval = DbOptExec_command_simple(client, "admin", "{}", &error);//     //     if (!retval) {//         ShowErrMsg("{}", &error);//     }    // cmd : empty    retval = DbOptExec_command_simple(client, "admin", "", &error);    if (!retval) {        ShowErrMsg("", &error);    }    /**    [] error : no such cmd:     */    // cmd : db    retval = DbOptExec_command_simple(client, "admin", "db", &error);    if (!retval) {        ShowErrMsg("db", &error);    }    /**    [db] error : no such cmd: db    */    /**    MongoDB shell version: 2.6.10    connecting to: test    > show dbs    Barca      0.078GB    admin      0.078GB    db_name    0.078GB    local      0.078GB    mongodb    0.078GB    test1      0.078GB    testdb     0.078GB    tutorial   0.078GB    yekai      7.950GB    >       > use test1      switched to db test1      > show collections      system.indexes      test1      >     */    // cmd : "{'drop': '%s'}"    retval = DbOptExec_command_simple(client, "admin", "use", "test1", &error);    if (!retval) {        ShowErrMsg("use test1", &error);    }    /**    [use test1] error : no such cmd: use    */    retval = DbOptExec_command_simple(client, "test1", "drop", "test1", &error);    if (!retval) {        ShowErrMsg("drop test1", &error);    }    /**    [drop] { "ns" : "test1.test1", "nIndexesWas" : 1, "ok" : 1.0 }    */    /** mongo console    > use test1    switched to db test1    > show collections    system.indexes    >     */    // cmd : getCmdLineOpts    retval = DbOptExec_command_simple(client, "admin", "getCmdLineOpts", &error);    if (!retval) {        ShowErrMsg("getCmdLineOpts", &error);    }    /**    [getCmdLineOpts] {         "argv" : [ "\/usr\/local\/mongodb\/bin\/mongod", "--config", "\/usr\/local\/mongodb\/bin\/mongodb.conf" ],         "parsed" : {             "config" : "\/usr\/local\/mongodb\/bin\/mongodb.conf",             "net" : { "http" : { "enabled" : false }, "port" : 27017 },             "processManagement" : { "fork" : true },             "storage" : { "dbPath" : "\/usr\/local\/mongodb\/db" },             "systemLog" : { "destination" : "file", "path" : "\/usr\/local\/mongodb\/logs\/mongodb.log" }             },         "ok" : 1.0         }    */    mongoc_collection_destroy(collection);    mongoc_database_destroy(database);    mongoc_client_destroy(client);    mongoc_cleanup();    return 0;}

mongo函数的封装

// @file MongoDbEx.h// @brief Mongo database operation#ifndef __MONGODB_EX__#define __MONGODB_EX__#include <bson.h>#include <bcon.h>#include <mongoc.h>#ifndef BOOLtypedef bool BOOL;#define TRUE 1#define FALSE 0#endif // #ifndef BOOLBOOL DbOptInit();BOOL DbOptUnInit();mongoc_client_t* DbOptOpenConect(const char* pConnectUrl);void DbOptCloseConect(mongoc_client_t*& pDbConnect);mongoc_database_t* DbOptOpenDb(mongoc_client_t* pDbConnect, const char* pDbName);void DbOptCloseDb(mongoc_database_t*& pDb);mongoc_collection_t* DbOptOpenTbl(mongoc_database_t* pDb, const char* pTblName);void DbOptCloseTbl(mongoc_collection_t*& pTbl);bool DbOptExec_command_simple(mongoc_client_t* pClient, const char* pcDbName, const char* pcCommand, bson_error_t* pError);bool DbOptExec_command_simple(mongoc_client_t* pClient, const char* pcDbName, const char* pcCommand, const char* pcValue, bson_error_t* pError);void ShowErrMsg(const char* pTip, bson_error_t* error);void ShowReply(const char* pTip, bson_t* reply);bson_t* new_formatv_bson(const char *json, ...);char* single_quotes_to_double (const char* str);#endif // #ifndef __MONGODB_EX__

// @file MongoDbEx.cpp// @brief ...#include "MongoDbEx.h"BOOL DbOptInit(){    mongoc_init();}BOOL DbOptUnInit(){    mongoc_cleanup();}mongoc_client_t* DbOptOpenConect(const char* pConnectUrl){    mongoc_client_t* pDbClient = NULL;    if (NULL != pConnectUrl) {        pDbClient = mongoc_client_new(pConnectUrl);    }    return pDbClient;}void DbOptCloseConect(mongoc_client_t*& pDbConnect){    if (NULL != pDbConnect) {        mongoc_client_destroy(pDbConnect);        pDbConnect = NULL;    }}mongoc_database_t* DbOptOpenDb(mongoc_client_t* pDbConnect, const char* pDbName){    mongoc_database_t* pDb = NULL;    if (NULL != pDbConnect) {        pDb = mongoc_client_get_database(pDbConnect, pDbName);    }    return pDb;}void DbOptCloseDb(mongoc_database_t*& pDb){    if (NULL != pDb) {        mongoc_database_destroy(pDb);        pDb = NULL;    }}mongoc_collection_t* DbOptOpenTbl(mongoc_database_t* pDb, const char* pTblName){    mongoc_collection_t* pTbl = NULL;    pTbl = mongoc_database_get_collection(pDb, pTblName);    return pTbl;}void DbOptCloseTbl(mongoc_collection_t*& pTbl){    if (NULL != pTbl) {        mongoc_collection_destroy(pTbl);        pTbl = NULL;    }}bool DbOptExec_command_simple(mongoc_client_t* pClient, const char* pcDbName, const char* pcCommand, bson_error_t* pError){    bool retval = false;    bson_t* command = NULL;    bson_t reply;    do {        command = BCON_NEW(pcCommand, BCON_INT32(1));        // mongoc_client_command_simple 作用: 让mongodb执行一些命令, 返回一些结果        retval = mongoc_client_command_simple(pClient, pcDbName, command, NULL, &reply, pError);        if (!retval) {            break;        } else {            ShowReply(pcCommand, &reply);        }    } while (0);    bson_destroy(&reply);    bson_destroy(command);    return retval;}bool DbOptExec_command_simple(mongoc_client_t* pClient, const char* pcDbName, const char* pcCommand, const char* pcValue, bson_error_t* pError){    bool retval = false;    bson_t reply;    bson_t* doc = NULL;    char *sz_cmd = NULL;    do {        // mongoc_client_command_simple 作用: 让mongodb执行一些命令, 返回一些结果        sz_cmd = bson_strdup_printf ("{'%s': '%s'}", pcCommand, pcValue);        doc = new_formatv_bson("%s", sz_cmd);        retval = mongoc_client_command_simple(pClient, pcDbName, doc, NULL, &reply, pError);        bson_free (sz_cmd);        if (!retval) {            break;        } else {            ShowReply(pcCommand, &reply);        }    } while (0);    bson_destroy(&reply);    bson_destroy(doc);    return retval;}void ShowErrMsg(const char* pTip, bson_error_t* error){    if (NULL != error) {        fprintf(stderr, "[%s] error : %s\n\n", (NULL != pTip) ? pTip : "", error->message);    }}void ShowReply(const char* pTip, bson_t* reply){    char* str = NULL;    if (NULL != reply) {        str = bson_as_json(reply, NULL);        if (NULL != str) {            printf("[%s] %s\n\n", (NULL != pTip) ? pTip : "", str);            bson_free(str);        }    }}bson_t* new_formatv_bson(const char *json, ...){    va_list args;    bson_error_t error;    char *formatted;    char *double_quoted;    bson_t *doc;    if (json) {        va_start (args, json);        formatted = bson_strdupv_printf (json, args);        va_end (args);        double_quoted = single_quotes_to_double (formatted);        doc = bson_new_from_json ((const uint8_t *) double_quoted, -1, &error);        if (!doc) {            fprintf (stderr, "%s\n", error.message);            abort ();        }        bson_free (formatted);        bson_free (double_quoted);    } else {        doc = bson_new ();    }    return doc;}char* single_quotes_to_double (const char* str){    char *result = bson_strdup (str);    char *p;    for (p = result; *p; p++) {        if (*p == '\'') {            *p = '"';        }    }    return result;}

makefile

# testcase by lostspeed# cmd is : ./Makefileclearrm ./testcaserm ./*.olsg++ -c MongoDbEx.cpp -o myDbOpt.o \    -I/usr/local/mongo_c162_driver/include/libmongoc-1.0 \    -I/usr/local/mongo_c162_driver/include/libbson-1.0 \    -L/usr/local/lib \    -L/usr/local/mongo_c162_driver/lib \    -lpthread \    -lmongoc-1.0 \    -lbson-1.0ls  g++ testcase_main.cpp myDbOpt.o -o testcase \    -I/usr/local/mongo_c162_driver/include/libmongoc-1.0 \    -I/usr/local/mongo_c162_driver/include/libbson-1.0 \    -L/usr/local/lib \    -L/usr/local/mongo_c162_driver/lib \    -lpthread \    -lmongoc-1.0 \    -lbson-1.0ls./testcase