Database Setup

The ACME CSE uses a database to store resources and other runtime data. You have the choice between a memory-based datatabase, a simple file-based database and a PostgreSQL database.

TinyDB File-Based

The default database is a simple but fast file-based database using the TinyDB library. By default, it requires no additional setup.

The database files are stored by default in the directory {baseDirectory}/data (which can be changed by a configuration setting).

You enable the TinyDB database by setting the databaseType setting in the [basic.config] section to tinydb:

Enable TinyDB as database

[basic.config]
databaseType=tinydb

TinyDB In-Memory

TinyDB also provides a memory-based database that might be useful for testing and development purposes, or if you want to start with a clean database each time you start the CSE.

You enable the in-memory database by setting the databaseType setting in the [basic.config] section to memory:

Enable in-memory database

[basic.config]
databaseType=memory

PostgreSQL

An alternative to the file-based database is to use a PostgreSQL database. This requires a running PostgreSQL server to which the CSE can connect. The PostgreSQL connection settings are configured in the acme.ini configuration file.

The following steps describe how to set up a PostgreSQL database for the ACME CSE:

Optional: Install PostgreSQL on your system. You can download the installer from the PostgreSQL website.
Create a new database and user for the CSE. It is recommended to use the CSE-ID as the database name and as the role name.
For example, you can use the following commands to create a new database named id-in and a role named id-in with the password acme:

Create database and role

psql -c "CREATE DATABASE \"id-in\";"
psql -c "CREATE USER \"id-in\" WITH PASSWORD 'acme';"
psql -c "GRANT ALL PRIVILEGES ON DATABASE \"id-in\" TO \"id-in\";"

If not done during the setup procedure above: Edit the acme.ini configuration file and the following settings under the [database.postgresql] section:
PostgreSQL database settings
```
    [database.postgresql]
    password = acme
```
All other settings are optional and can be left at their default values. The database and role settings are set to the CSE-ID by default. If you used different names for the database and role, you have to adjust these settings accordingly. Also the host and port settings are set to localhost and 5432 by default. If your PostgreSQL server is running on a different host or port, you have to adjust these settings as well.
You also need to enable the PostgreSQL database by setting the databaseType setting in the [basic.config] section to postgresql:
Enable postgreSQL database
```
    [basic.config]
    databaseType=postgresql
```
Run the CSE.
The database schema, tables and other structures are created automatically by the CSE when it starts and connects for the first time.

Disabling PostgreSQL Support

Sometimes it may not be possible or desirable to use a PostgreSQL database, for example, when running the CSE on a system where PostgreSQL is not available or when you want to use the CSE in a simple test environment.

In this case, you can disable the PostgreSQL database by setting the databaseType setting in the [basic.config] section to tinydb or memory:

Disable PostgreSQL database

[basic.config]
databaseType=tinydb

In order to prevent the PostgreSQL Python modules (i.e. psycopg2) to be loaded you can also set the ACME_NO_PGSQL environment variable to any value before running the CSE:

Disable PostgreSQL Database Support in Environment

export ACME_NO_PGSQL=1