Update readme

Author: timbeccue

README.md

@@ -1,3 +1,49 @@
 # ocs-example-frontend
 
 This is a frontend project demonstrating use of the ocs-components-lib, and the general capabilities of an observatory control system.
+
+The easiest way to interact with this frontend is to run a full example project with the [ocs_example](https://github.com/observatorycontrolsystem/ocs_example).
+
+## Environment variables
+
+| Variable                              | Description                           | Default                 |
+| ------------------------------------- | ------------------------------------- | ----------------------- |
+| `VUE_APP_OBSERVATION_PORTAL_API_URL`  | Observation portal API URL            | `http://127.0.0.1:8000` |
+
+## Project setup
+
+Install the frontend dependencies:
+```
+npm install
+```
+
+### Local Development
+
+If you are developing locally, you will need to have a running [observation portal](https://github.com/observatorycontrolsystem/observation-portal). 
+
+Make sure you enable cross origin resource sharing for the frontend domain when running the observation portal. For example, if your frontend is running at `http://127.0.0.1:8080`, you could set the following environment variables for the observation portal:
+
+``` bash
+export CORS_ORIGIN_WHITELIST=http://127.0.0.1:8080
+export CSRF_TRUSTED_ORIGINS=127.0.0.1:8080
+```
+
+Then, to run a hot-reload server for developing on the frontend:
+```
+npm run serve
+```
+
+### Compile and minify for production
+```
+npm run build
+```
+
+### Lint and fix files
+```
+npm run lint:fix
+```
+
+### Check for linting errors without fixing them
+```
+npm run lint:check
+```