ncsa/checks repository overview

⁠NCSA CHECKS

The goal of this project is to have a simple set of functions that can be used as init containers in your kubernetes deployment. Each of the checks will see if the service is ready to accept connections.

For example the following snippet will wait for rabbitmq and postgresql to be ready before starting the actual container:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: mywebapp
spec:
  replicas: 1
  selector:
    matchLabels:
      app: mywebapp
  template:
    metadata:
      labels:
        app: mywebapp
    spec:
      initContainers:
        - name: check-rabbitmq
          image: "ncsa/checks:1.0.0"
          env:
            - name: RABBITMQ_URI
              value: "amqp://user:pass@rabbitmq/%2F"
        - name: check-postgresql
          image: "ncsa/checks:1.0.0"
          env:
            - name: PGURI
              value: "postgresql://postgres:secret@postgresql:5432/mydb"
            - name: PGTABLE
              value: "users"
      containers:
        - name: mywebapp
          image: mywebapp:1.0
          ports:
            - containerPort: 80
          env:
            - name: RABBITMQ_URI
              value: "amqp://user:pass@rabbitmq/%2F"
            - name: PGHOST
              value: "postgres"
            - name: PGUSER
              value: "postgres"

⁠Tests Supported

RabbitMQ

• description : checks to see if can connect to RabbitMQ Server
• exit code : 1
• parameters
  • RABBITMQ_URI [required] : URI for RabbitMQ server

Mongo

• description : checks to see if can connect to MongoDB Server
• exit code : 2
• parameters
  • MONGO_URI [required] : URI for MongoDB server

URL

• description : checks to see if URL is reachable and returns status code of 200. If optional text is given the text needs to be in the returned body.
• exit code : 3
• parameters
  • URL [required] : URL to check
  • URL_TEXT [optional] : text to be found in body returned

PostgreSQL

• description : checks to see if database is up. Will check to see if the optional table exists
• exit code : 4
• parameters
  • PGURI [required*] : URI to connect to postgresql.
  • PGUSER [required*] :
  • PGPASSWORD [required*] :
  • PGHOST [required*] :
  • PGPORT [required*] :
  • PGDATABASE [required*] :
  • PGTABLE [optional] : table that should exist

• either PG_URI or on of the PG* should be provided.

⁠TODO:

• check_service: check if host:port is reachable
• create simple tests for each check
• add db/collection for mongo to test access