feat: add backend

README.md

@@ -0,0 +1,70 @@
+[![pipeline status](https://img.shields.io/gitlab/pipeline/openstapps/backend.svg?style=flat-square)](https://gitlab.com/openstapps/backend/commits/master)
+# backend (a reference implementation of a StApps backend)
+This project is a reference implementation for a StApps backend. It provides an HTTP API to index data into a database,
+perform full text search, sorts and filters. It also delivers the configuration needed by the app. The API is specified
+within the [@openstapps/core](https://gitlab.com/openstapps/core).
+
+If you want to perform requests, index data or search within JavaScript or TypeScript you should consider using
+[@openstapps/api](https://gitlab.com/openstapps/api)
+
+# Usage
+This backend is not a standalone software. It needs a database like Elasticsearch to work.
+
+If you just want to use the backend you should consider using
+[minimal-deployment](https://gitlab.com/openstapps/minimal-deployment). The minimal-deployment will provide
+you with everything you need to run this backend.
+
+# Local usage for development purposes
+## Requirements
+* Elasticsearch (5.5)
+* Node.js (~10) / NPM
+* Docker
+
+## Start Database (Elasticsearch)
+Elasticsearch needs some configuration and plugins to be able to work
+with the backend. To save you some work we provide a
+[docker image](https://gitlab.com/openstapps/database) which
+only needs to be executed to work with the backend.
+
+Run `docker run -d -p 9200:9200 registry.gitlab.com/openstapps/database:master`
+
+Elasticsearch should be running at port 9200 now. If you have problems with
+getting elasticsearch to work, have a look in the
+[README](https://gitlab.com/openstapps/database) of the image
+first.
+
+## Start backend
+Run `npm install` and `npm run build`, then start with `npm start`. The server should now be accepting connections at `http://localhost:3000`.
+
+# Environment Variables
+To select a database implementation you have to set the `NODE_CONFIG_ENV` variable. At the time only `NODE_CONFIG_ENV=elasticsearch` is supported.
+Set `NODE_ENV=production` to run backend for production usages. In production the backend expects some kind of monitoring to be set via the
+environment. At the time only SMTP is being implemented. The backend wouldn't start if you don't provide SMTP authentification. Alternatively
+you can set `ALLOW_NO_TRANSPORT=true`. To set up an SMTP configuration have a look at
+[@openstapps/logger](https://gitlab.com/openstapps/logger).
+
+## Config files
+Each university can have it's specific config for the general backend and app and for all databases.
+
+All config files can be found in `./config/`. There is a `default.ts` which is used by default. You can create an
+university specific file with following naming scheme: `default-<university license plate>.ts`
+
+A university specific file will only overwrite all properties of the `default.ts` that are set in the file itself.
+To start the backend using your configuration you have to provide the `NODE_APP_INSTANCE` environment variable
+with your university license plate.
+
+To set a database you have to provide the `NODE_CONFIG_ENV` environment variable with the name of the database.
+At the time only Elasticsearch is implemented.
+
+To create your university specific config file for the elasticsearch you have to create a file with following naming
+scheme: `elasticsearch-<university license plate>.ts`.
+
+## Debugging
+Set `ES_DEBUG=true` to enable verbose Elasticsearch tracing information.
+This can be useful to debug some issues between backend and elasticsearch.
+
+## Setting a different url for elasticsearch
+Set `ES_PORT_9200_TCP_ADDR` to change the elasticsearch-http-address which by default is `localhost`.
+Set `ES_PORT_9200_TCP_PORT` to change the elasticsearch port which by default is `9200` .
+
+## [Contributing](https://gitlab.com/openstapps/projectmanagement/blob/master/CONTRIBUTING.md)