cachedb_mongodb Module

Vladut-Stefan Paiu

   OpenSIPS Solutions

Edited by

Vladut-Stefan Paiu

   Copyright © 2013-2017 www.opensips-solutions.com
     __________________________________________________________

   Table of Contents

   1. Admin Guide

        1.1. Overview
        1.2. Advantages
        1.3. Limitations
        1.4. Dependencies

              1.4.1. OpenSIPS Modules
              1.4.2. External Libraries or Applications

        1.5. Exported Parameters

              1.5.1. cachedb_url (string)
              1.5.2. exec_threshold (int)
              1.5.3. compat_mode_2.4 (int)
              1.5.4. compat_mode_3.0 (int)

        1.6. Exported Functions
        1.7. Raw Query Syntax

   List of Examples

   1.1. Runtime requirements for "cachedb_mongodb"
   1.2. Compilation requirements for "cachedb_mongodb"
   1.3. Set cachedb_url parameter
   1.4. Use MongoDB servers
   1.5. Set exec_threshold parameter
   1.6. Setting the compat_mode_2.4 parameter
   1.7. Setting the compat_mode_3.0 parameter
   1.8. MongoDB Raw Insert
   1.9. MongoDB Raw Update

Chapter 1. Admin Guide

1.1. Overview

   This module is an implementation of a cache system designed to
   work with MongoDB servers. It implements the Key-Value
   interface exposed by the OpenSIPS core.

   The underlying client library is compatible with any of the
   following MongoDB server versions: 2.4, 2.6, 3.0, 3.2 and 3.4,
   as stated in the MongoDB documentation.

1.2. Advantages

     * memory costs are no longer on the server
     * many servers can be used inside a cluster, so the memory is
       virtually unlimited
     * the cache is 100% persistent. A restart of OpenSIPS server
       will not affect the DB. The MongoDB is also persistent so
       it can also be restarted without loss of information.
     * MongoDB is an open-source project so it can be used to
       exchange data with various other applications
     * By creating a MongoDB Cluster, multiple OpenSIPS instances
       can easily share key-value information
     * This module also implements the CacheDB Raw query
       capability, thus you can run whatever query that the
       MongoDB back-end supports, taking full advatange of it.

1.3. Limitations

     * keys (in key:value pairs) may not contain spaces or control
       characters

1.4. Dependencies

1.4.1. OpenSIPS Modules

   None.

1.4.2. External Libraries or Applications

   The following packages must be installed before running
   OpenSIPS with this module loaded:

   Example 1.1. Runtime requirements for "cachedb_mongodb"
# Debian / Ubuntu
sudo apt-get install libjson-c2 libmongoc-1.0

# Red Hat / CentOS
sudo yum install json-c mongo-c-driver

   The following packages are required in order to compile this
   module:

   Example 1.2. Compilation requirements for "cachedb_mongodb"
# Debian / Ubuntu
sudo apt-get install libjson-c-dev libmongoc-dev libbson-dev

# Red Hat / CentOS
sudo yum install json-c-devel mongo-c-driver-devel

1.5. Exported Parameters

1.5.1. cachedb_url (string)

   The URLs of the server groups that OpenSIPS will connect to in
   order to allow the cache_store(), cache_fetch(), etc. functions
   to be used from the OpenSIPS script. It can be set more than
   one time. The prefix part of the URL will be the identifier
   that will be used from the script.

   The URL syntax is identical to the one used by MongoDB,
   including connect string options. For more info, please refer
   to the official MongoDB connect string documentation.

   Example 1.3. Set cachedb_url parameter
...
modparam("cachedb_mongodb", "cachedb_url","mongodb:instance1://localhost
:27017/db.collection")
modparam("cachedb_mongodb", "cachedb_url","mongodb:replicaset1://1.2.3.4
:27017,2.3.4.5:27017,3.4.5.6:27017/db.collection?replicaSet=test")
...

   Example 1.4. Use MongoDB servers
...
cache_store("mongodb:group1", "key", "$ru value");
cache_fetch("mongodb:replicaset1", "key", $avp(10));
cache_remove("mongodb:cluster1", "key");
...

1.5.2. exec_threshold (int)

   The maximum number of microseconds that a mongodb query can
   last. Anything above the threshold will trigger a warning
   message to the log

   Default value is “0 ( unlimited - no warnings )”.

   Example 1.5. Set exec_threshold parameter
...
modparam("cachedb_mongodb", "exec_threshold", 100000)
...

1.5.3. compat_mode_2.4 (int)

   Switch the module into compatibility mode for MongoDB 2.4
   servers. Specifically, this allows "insert/update/delete" raw
   queries to not fail, since they were introduced in MongoDB 2.6.
   The module will interpret the raw query JSON, convert it to its
   corresponding command and run it.

   Caveat: only the minimally required raw query options are
   supported in this mode.

   Default value is “0 (disabled)”.

   Example 1.6. Setting the compat_mode_2.4 parameter
...
modparam("cachedb_mongodb", "compat_mode_2.4", 1)
...

1.5.4. compat_mode_3.0 (int)

   Switch the module into compatibility mode for MongoDB 2.6/3.0
   servers. Specifically, this allows "find" raw queries to not
   fail, since they were introduced in MongoDB 3.2. The module
   will interpret the "find" raw query JSON, convert it to its
   corresponding command and run it.

   Caveat: only the minimally required options for "find" raw
   queries are supported in this mode.

   Default value is “0 (disabled)”.

   Example 1.7. Setting the compat_mode_3.0 parameter
...
modparam("cachedb_mongodb", "compat_mode_3.0", 1)
...

1.6. Exported Functions

   The module does not export functions to be used in
   configuration script.

1.7. Raw Query Syntax

   The cachedb_mongodb module supports raw queries, thus taking
   full advantage of the capabilities of the back-end, including
   query-specific options such as read/write preference, timeouts,
   filtering options, etc.

   The query syntax is identical to the mongo cli. Documentation
   for it can be found on the MongoDB website. Query results are
   returned as JSON documents, that one can further process in the
   OpenSIPS script by using the JSON module.

   Some example raw queries:

   Example 1.8. MongoDB Raw Insert
...
cache_raw_query("mongodb:cluster", "{ \
    \"insert\": \"ip_blacklist\", \
    \"documents\": [{ \
        \"username\": \"$fU\", \
        \"ip\": \"$si\", \
        \"attempts\": 1 \
     }]}",
 "$avp(out)");
xlog("INSERT RAW QUERY returned $rc, output: '$avp(out)'\n");
...

   Example 1.9. MongoDB Raw Update
...
cache_raw_query("mongodb:cluster", "{ \
    \"update\": \"ip_blacklist\", \
    \"updates\": [{ \
        \"q\": { \
            \"username\": \"$fU\", \
            \"ip\": \"$si\" \
         }, \
        \"u\": { \
            \"$$inc\": {\"attempts\": 1} \
         } \
      }]}",
 "$avp(out)");
xlog("UPDATE RAW QUERY returned $rc, output: '$avp(out)'\n");
...
