Experimental Database

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The experimental database keeps track of:

1. experiments (experiment table)
2. experiment team members (experimentteams table)
3. users in the team (user)
4. roles in the team (role)

The data is populated centrally from the Experiment Database Populator (alternatively named RB number populator) which is run on control-svcs. The RB numbers were populated by a different service on SECI, which can be found at https://github.com/ISISNeutronMuon/RBNumberFinder.

Architecture

The experiment database populator is a Python 3.8 program that is designed to run centrally and periodically update instrument databases. It does the following:

• Monitors 'CS:INSTLIST' for instruments that are scheduled
• Gathers 200 days worth of data from the web services hosted by business apps (Using the credentials stored in a git repository on the local share).
• Reformats the data slightly to match the structure of the instrument databases
• Pushes to the instrument database (Using the credentials stored in a git repository on the local share).
• Optionally repeats every hour

Testing

• If it is the first time running the populator you will need to install Python 3.8 (any distribution should do) and ensure that you pip install the requirements listed in requirements.txt
• The populator has unit tests that are run in jenkins.
• You will need to add access permission for the populator to write to your local database, to do this run EPICS/SystemSetup/create_test_account.bat
• You can write some dummy test data into your local database by using the --test_data argument. If you do not have access to the private share you can also specify the username and password for writing to the database using the --db_user and --db_pass flags. The username/password can be found in EPICS/SystemSetup/test_account.sql.

Deployment

The Experiment Database Populator needs to be deployed using a Python 3.8 virtual environment as the the repository is not compatible with the version of python installed system wide.

Please follow the below instructions as part of deploying:

• Make sure you are firstly a super user to epics using the following command: sudo su - epics
• Pull most recent changes from master in home/epics/RB_num_populator
• From home/epics/RB_num_populator, check that a python 3.8 virtual environment exists called "exp_db_populator_venv".
• Activate virtual environment if present and check /home/epics/RB_num_populator/requirements.txt file matches dependencies in venv and then deactivate the virtual environment.
• If there is no virtual environment called "exp_db_populator_venv" or dependencies are not inline with /home/epics/RB_num_populator/requirements.txt, run /home/epics/RB_num_populator/create_rb_number_populator_python_venv.sh and check the virtual environment has been created.
• Check that the cron job is running correctly using the following command: crontab -l. The output should look similar to: 20 * * * * sh /home/epics/RB_num_populator/rb_number_populator.sh > /tmp/rb_num_pop.out 2>&1
• Finally, check cron job is executing correctly by looking at recent logs since deploying under /home/epics/RB_number_populator/logs and for any errors indicating the cron job is not executing correctly under /tmp/rb_num_pop.out.