Introduction

This is the backend to the Human perception survey (percept) project. It expects to interact with a frontend server, see Percept Frontend.

It depends on Node.js (developed with version 18.14.2) and PostgreSQL (preferably version 13 or greater) with PostGIS (preferably version 3.3.2 or better).

Configuration

Copy config.js.sample to config.js and edit the values in the file according to the comments.

Create your databases and enable PostGIS in them, most likely you will want to do this as the postgres database administrator user on most Linux distributions.

For example:

• sudo -u postgres createdb -O $USER percept-test
• sudo -u postgres psql -c 'CREATE EXTENSION postgis;' percept-test
• sudo -u postgres createdb -O $USER percept-dev
• sudo -u postgres psql -c 'CREATE EXTENSION postgis;' percept-dev
• sudo -u postgres createdb -O $USER percept-prod
• sudo -u postgres psql -c 'CREATE EXTENSION postgis;' percept-prod

Seeding the database

You will need to populate the database with imagery. A recommended way to do that is to use the vsvi-filter to create SQL files with INSERT statements. Those SQL files can be placed in the seeds/dev, seeds/test, or seeds/prod directory depending on whether you want to use the imagery for development, testing or production purposes. The database migration scripts db-up.sh and db-down.sh (described below) will then pick them up automatically.

Available Scripts

In the project directory, you can run:

npm install

Downloads, builds and installs the necessary dependencies to run the app. Run this before anything else.

./db-up.sh [dev | prod | test]

./db-down.sh [dev | prod | test]

Creates or drops the database tables and various seed values. The name of the database is percept-$kind where $kind is either 'dev', 'prod' or 'test'. The default kind is 'dev'. The main difference is the seeds that are used. The 'dev' database is initialised with many fewer values, just enough for development purposes. 'test' is mainly used by the testsuite.

These scripts expect to be able to run psql commands freely. If psql is not working on your databases then that needs to be sorted out with your PostgreSQL setup first.

npm run dev

Runs the app in the development mode.

The server will reload when you make changes.
You may also see any lint errors in the console.

npm start

Runs the app in production mode.

npm test

Runs the test suite on the test database (testdbname in config.js).

License

This project is released under the GNU GPL v3.0. Please see COPYING for more details.