Investigation into GKE-Knative-Istio functionality

This repository is the outcome of investigating the features and functionalities of:

• Istio
• Knative
• GCP Config Connector
• Jaeger - Kiali and other GUIs

Fair warning

This codebase will be a bit hacky at times as its mostly proving the viability rather than making a nice implementation.

Architecture

• [istio-ingressgateway] - Entrance point of the application from the outside world
• [ship-request-api] - Service with readonly access to the database - Put requests not yet implemented (Service is never intended to have write access to db)
• [ship-request-frontend] - Simple static website
• [ship-store-mongodb] - Simple database setup that stores all notifications
• [normaliser-event-notification] - Service that listens to ingress pubsub messages and normalises them
• [ship-event-add-notification] - Service that listens for normalised pubsub messages and enters them into the database - This service has write access and no public interface.

Standards, Practices, Sidecars & Meshes

In the knativeless version the normaliser-event-notification and ship-event-add-notification services both use the pubsub-connector-sidecar sidecar. This sidecar handles the integration with gcp pubsub.

The normaliser-event-notification and ship-event-add-notification services both follow the cloudevents spec, to have a standard format for incoming messages. This means these services work in both the knative and knativeless environments.

The ship-request-api service has authentication in-front of its /notifications endpoint, which is managed by istio. This authentication is done in the ship-request-frontend.

Flow

You can send example messages to gcp pubsub by running the ./send.sh command. The ./send.sh command supports ./send.sh 1 and ./send.sh 2 to send payloads in different formats.

The messages are then picked up by the normaliser-event-notification service which publishes the normalised versions back to gcp pubsub.

The normalised messages are then picked up by the ship-event-add-notification service which saves the entry to the database.

There is currently no fancy logic within these services other than the specific intended purpose to prove the functionalities of the platform.

Message Formats

Un-normalised Message Type 1:

{ "version": 1, "id": "1x0d", "name": "Golden Sausage", "captain": "Duke Lordship", "position": "49.2144,2.1312", "speed": { "velocity": 41, "unit": "Knots" } }

{ "version": 1, "id": "1x0d", "name": "Golden Sausage", "captain": "Duke Lordship", "position": "49.2144,2.1312", "speed": { "velocity": 47, "unit": "Miles" } }

Un-normalised Message Type 2:

{ "version": 2, "ship": { "registration": "1x0d", "name": "Golden Sausage" }, "captain": "Duke Lordship", "position": { "latitude": 49.2144, "longitude": 2.1312 }, "speed": 41 }

Normalised Message Type:

{ "registration": { "id": "1x0d", "name": "Golden Sausage", "captain": "Duke Lordship" }, "status": { "position": { "lat": 49.2144, "long": 2.1312 }, "velocity": 41 } }

Deployment

You will need to first build all the images, example: ./build.sh ship-request-frontend v1. The name of the service is the name of the docker file in deployments/docker.

There are currently two versions of the application. One with knative and one without.

Choose between deployments/kubernetes/ship-app-kafka and deployments/kubernetes/ship-app-knative.

At the moment you will probably need to tweak version numbers and some variables unless I make it more generic.

You will probably need to label your namespace like:

• kubectl label namespace ship-app-kafka istio-injection=enabled
• kubectl label namespace ship-app-kafka knative-eventing-injection=enabled # if using knative

Requirements

• Istio
  • istioctl manifest apply --set values.kiali.enabled=true --set values.tracing.ingress.enabled=true --set telemetry.enabled=true --set values.tracing.enabled=true --set values.global.tracer.zipkin.address=jaeger-collector.istio-system:9411
• Kubernetes
• Knative?
• Jaeger - Kiali?
  • https://www.jaegertracing.io/docs/1.13/operator/
• GCP Config Connector?