API Scout :: Finding Your APIs In Kubernetes

What is API Scout

API Scout, helps you get up-to-date API docs to your developers by simply annotating your services in K8s.

What are the components of API Scout

The docker image that is deployed to Kubernetes has several components:

• The container itself is based on nginx:1.15-alpine
• The webapp is a staticly generated site by Hugo using the Learn theme and Swagger UI
• A server app that connects to the Kubernetes cluster using a default role to watch for services that need to be indexed

Hugo is downloaded and embedded during the build of the container

Build and run

API Scout has a Makefile that can be used for most of the operations. Make sure you have installed Go Programming Language, set GOPATH variable and added $GOPATH/bin in your PATH

usage: make [target]

Makefile targets	Description
build-all	Performs clean-all and executes all build targets
build-docker	Builds a docker image from the dist directory
build-server	Builds the server app in dist
build-site	Builds the Hugo distribution in dist
clean-all	Removes the dist directory
clean-docker	Stops and removes all containers and images for apiscout
clean-kube	Removes the apiscout service and deployment from Kubernetes
deps	Get dependencies to build the server
minikube-delete	Delete the Minikube installation
minikube-install	Install Minikube on this machine
minikube-show	Show the API Scout UI that is deployed to Minikube
minikube-start	Start Minikube with default configuration
minikube-stop	Stop Minikube
run-docker	Runs a docker container with default settings
run-docs	Runs the embedded Hugo server on port 1313 for the documentation
run-hugo	Runs the embedded Hugo server on port 1313
run-kube	Deploys apiscout to Kubernetes
run-server	Builds the in the server directory and runs it with default settings
stop-docker	Stop and remove the running apiscout container

Requirements for Kubernetes

To be able to view the services, apiscout needs access to the Kubernetes cluster using the default service account. By default (pun intended) this account doesn't have access to view services so during deployment a new rolebinding is created. After starting, it will register a watcher with the Kubernetes API Server, so that it receives events when something occurs in the cluster.

apiscout looks for two annotations to be able to index a service:

• apiscout/index: 'true' This annotation ensures that apiscout indexes the service
• apiscout/swaggerUrl: '/swaggerspec' This is the URL from where apiscout will read the OpenAPI document

Environment variables for the docker container

apiscout has a few environment variables that the docker container (and thus the deployment to Kubernetes) can use:

• SWAGGERSTORE: The location where to store the swaggerdocs
• HUGOSTORE: The location where to store content for Hugo
• MODE: The mode in which apiscout is running (can be either KUBE or LOCAL)
• EXTERNALIP: The external IP address of the Kubernetes cluster in case of LOCAL mode
• HUGODIR: The base directory for Hugo

Getting started

This section provides minimal steps to get apiscout running inside a kubernetes cluster on local machine / VM of your choice.

Prerequisites

• Docker
• Kubernetes environment (for example minikube)

Steps to follow

1. Start minikube

$ make minikube-start

2. Build and deploy apiscout

# Install dependencies
$ make deps

# Build apiscout docker image
$ make build-all

• Update image with apiscout docker image name built in the previous step and EXTERNALIP value with minikube IP in apiscout.yml

# Deploy apiscout to Kubernetes
$ make run-kube

3. Build and deploy sample micro service

# Navigate to samples/invoiceservice-go folder
$ cd samples/invoiceservice-go

# Install dependencies
$ make deps

# Build sample microservice application
$ make build-app

# Build dcoker image with the sample microservice application
$ make build-docker

# Deploy sample application to Kubernetes
$ make run-kube

Testing

# Navigate back to apiscout directory
$ cd ../..

# Open kubernetes service url in a web browser to see sample application api specification in swagger format
$ make minikube-show

Note: If you face any issue with above command in linux, update Makefile with xdg-open instead of open command under minikube-show target.

Cleanup

# Delete sample application from Kubernetes
$ cd samples/invoiceservice-go
$ make clean-kube

# Delete apiscout from Kubernetes
$ cd ../..
$ make clean-kube

# Stop minikube
$ make minikube-stop

License

See the LICENSE file

The logo made by Freepik from www.flaticon.com is licensed by CC 3.0 BY