Mongo Historian

MongoDB is a NoSQL document database, which allows for great performance for transactional data. Because MongoDB documents do not have a schema, it is easy to store and query data which changes over time. MongoDB also scales horizontally using sharding.

Note

The MongodbHistorian is located within the unsupported directory.

services/unsupported/MongodbHistorian/

For more information about MongoDB, read the MongoDB documentation

Prerequisites

1. Mongodb

Setup mongodb based on using one of the three installation scripts for the corresponding environment:

  1. Install as root on Redhat or Cent OS

    sudo scripts/historian-scripts/root_install_mongo_rhel.sh

    The above script will prompt user for os version, db user name, password and database name. Once installed you can start and stop the service using the command:

    **sudo service mongod [start|stop|service]**

  2. Install as root on Ubuntu

    sudo scripts/historian-scripts/root_install_mongo_ubuntu.sh

    The above script will prompt user for os version, db user name, password and database name. Once installed you can start and stop the service using the command:

    **sudo service mongod [start|stop|service]**

  3. Install as non root user on any Linux machine

    scripts/historian-scripts/install_mongodb.sh

    Usage:

    install_mongodb.sh [-h] [-d download_url] [-i install_dir] [-c config_file] [-s]

    Optional arguments:

    -s setup admin user and test collection after install and startup

    -d download url. defaults to https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.2.4.tgz

    -i install_dir. defaults to current_dir/mongo_install

    -c config file to be used for mongodb startup. Defaults to default_mongodb.conf in the same directory as this script. Any data path mentioned in the config file should already exist and should have write access to the current user

    -h print the help message

2. Mongodb connector

This historian requires a mongodb connector installed in your activated VOLTTRON virtual environment to talk to MongoDB. Please execute the following from an activated shell in order to install it:

python bootstrap.py --mongo

or

python bootstrap.py --databases

or

pip install pymongo==3.7.2
pip install bson
pip install ujson

3. Configuration Options

The historian configuration file can specify

"history_limit_days": <n days>

which will remove entries from the data and rollup collections older than n days. Timestamps passed to the manage_db_size method are truncated to the day.