kurssisivu-backend

API

Backend specifies three endpoints

For testing

GET /ping

pongs.

Organization codes

GET /organizations

returns the organization codes saved in Redis.

Courses of organization(s)

GET /organizations/{codes}/courses_list.json?semester={semester}&year={year}

returns courses of the specified organizations.

• codes is a comma separated list of organization codes
  • if a code is not among the valid codes saved in Redis, response is 400 Bad request
• query parameters semester and year are optional
• valid values of semester are autumn, spring and summer
  • invalid semesters are ignored

Eg. to get spring 2018 courses of Department of Computer Science GET

https://opetushallinto.cs.helsinki.fi/organizations/500-K005,500-M009,500-M010/courses_list.json?semester=spring&year=2018

Response is a JSON-array of the type:

[
  {
    "start_date": "2018-03-11T22:00:00.000Z",
    "end_date": "2018-05-01T21:00:00.000Z",
    "credit_points": 5,
    "course_id": 119553005,
    "parent_id": null,
    "learningopportunity_id": "TKT21004",
    "languages": [{
        "langcode": "en"
      },
      {
        "langcode": "fi"
      }
    ],
    "realisation_name": [{
      "langcode": "fi",
      "text": "Computer Organization II"
    }],
    "realisation_type_code": 5,
    "organisations": [
      "500-K005"
    ],
    "periods": [
      4
    ],
    "years": [
      2018
    ],
    "learningopportunity_type_code": 2
  }
]

NOTE response includes now keys periods and years. The current version of the fronend has a logic for calculationg the period of the course (see here) which should be deprecated (since it does not work properly) and the period info provided by API used instead.

Configuration

Backend uses the following environment variables (default values at right):

COURSES_KEY=courses
ORGANIZATIONS_KEY=codes
LEARNING_OPPORTUNITIES_KEY=opportunities
REDIS_HOST=localhost
REDIS_PORT=6379
PORT=3001
OODI_BASE_URL=

Development

Fetch dependencies: npm install

Run backend: npm run watch

• To get any meaningful responses, course info should be cached in Redis by running the updater

Run cache updater: npm run updater

Initialisation of Redis

Before running updater, organization codes should be saved in Redis with key ORGANIZATIONS_KEY as a json of the form

[
  "400-K005", 
  "400-K006",
  "500-K001",
  "500-K002",
  "500-K003",
  "500-K004",
  "500-K005",
  "500-M001", 
  "500-M002", 
  "500-M008",
  "500-M009", 
  "500-M010"
]

Initialisation can be done by running node init_organisations.js ./organisation_codes.json

where ./organisation_codes.json is the location of codes in JSON format.

Tests

Run with: npm test

Coverage raport: npm run coverage 

Production setup

Currently Travis runs tests and on success builds a new docker image toska/coursepage-backend and pushes that to DockerHub

Backend

docker-compose.yml for backend and Redis:

version: '3.5'

services:
 backend:
   environment:
     COURSES_KEY: courses
     ORGANIZATIONS_KEY: codes
     LEARNING_OPPORTUNITIES_KEY: opportunities
     REDIS_HOST: redis
     REDIS_PORT: 6379
     PORT: 3001
   image: toska/coursepage-backend
   restart: unless-stopped
   ports:
     - "3005:3001"
   container_name: coursepage-backend
   depends_on:
      - "redis"
   volumes:
     - ./data:/data
     - ./logs:/usr/src/app/logs
   command: ["npm", "start" ]

 redis:
   image: redis
   command: ["redis-server", "--appendonly", "yes"]
   restart: unless-stopped
   container_name: coursepage-redis
   volumes:
     - ./redis-data:/data
   networks:
     - redis
     - default

networks:
  redis:
    driver: bridge
    name: redis

Redis saves data in directory ./redis-data, you need also directory ./data for initialising the organisation codes in Redis.

Logs are saved in directory ./logs, currently backend is not logging much.

Deploy with:

#!/bin/bash
docker login -u $DOCKER_USER -p $DOCKER_PW
docker-compose pull&&docker-compose up -d

Initialising organisation codes

Once backend is running, assuming that you have organization codes as JSON-array in file ./data/organisation_codes.json, save those to Redis with

docker exec -i -t coursepage-backend node init_organisations.js /data/organisation_codes.json

Cache updater

docker-compose.yml for updater:

version: '3.5'

services:
 backend:
   environment:
     COURSES_KEY: courses
     ORGANIZATIONS_KEY: codes
     LEARNING_OPPORTUNITIES_KEY: opportunities
     REDIS_HOST: redis
     REDIS_PORT: 6379
     OODI_BASE_URL: https://esbmt1.it.helsinki.fi/doo-oodi/v1/productiondb
   image: toska/coursepage-backend
   container_name: coursepage-updater
   volumes:
     - ./data:/data
     - ./logs:/usr/src/app/logs
   networks:
     - redis
     - default
   command: ["npm", "run", "updater" ]

networks:
  redis:
    external: true

Run with

#!/bin/bash
docker-compose stop&&docker-compose up -d