Installation

0. Get rcdb

Clone this repository:

git clone https://github.com/JeffersonLab/rcdb.git

1. Install python requirements

cd rcdb
pip install -r requirements.txt

2. Set environment

There are environment.<your shell> scripts, which automatically set environment variables for the of rcdb

source environment.bash   # for bash

The script sets $RCDB_HOME to RCDB root directory, appends $PYTHONPATH and $PATH. The full list of variables set by the script and how to set them manually one can read below.

3. Database connection

One needs so called "connection string" in order to connect to database. For now we consider to use MySQL and SQLite databases. The connection strings for them are:

MySQL

mysql://user_name:password@host:port/database

SQLite

sqlite:///path_to_file

(!) Note that because SQLite doesn't have user_name and password, it starts with three slashes ///. And thus there should be four slashes //// in absolute path to file.

sqlite:////home/user_name/rcdb.sqlite.db

RCDB_CONNECTION

The common way of different parts of RCDB to know the connection string is to set RCDB_CONNECTION environment variable:

#bash: 
export RCDB_CONNECTION="mysql://rcdb@hallddb.jlab.org/rcdb"

The other common way is to set -c \<connection string\> key

4. Experimenting

To experiment with RCDB and examples below, there is create_empty_sqlite.py script in $RCDB_HOME/python folder. The script creates empty sqlite database. The usage is:

python $RCDB_HOME/python/create_empty_sqlite.py path_to_database.db

One can download HALLD sqlite database (autogenerated daily) here:

https://halldweb.jlab.org/dist/rcdb.sqlite

Setup environment manually

If one needs to setup environment variables manually, here is the list of variables, environment.XXX scripts set:

RCDB_HOME - set to the rcdb directory (where environment.* scripts are located)
PYTHONPATH - add $RCDB_HOME/python - in order to import rcdb module from python
PATH - add "$RCDB_HOME":"$RCDB_HOME/bin":$PATH

If one wants to use C++ readout API