Smocker (server mock) is a simple and efficient HTTP mock server.

The documentation is available on smocker.dev.

Table of contents

• Installation
  • With Docker
  • Manual Deployment
  • Healthcheck
  • User Interface
• Usage
  • Hello, World!
• Mock format schema
• Development
  • Backend
  • Frontend
  • Docker
  • Caddy
  • HTTPS
• Authors
• Contributors

Installation

With Docker

docker run -d \
  --restart=always \
  -p 8080:8080 \
  -p 8081:8081 \
  --name smocker \
  ghcr.io/smocker-dev/smocker

Manual Deployment

# This will be the deployment folder for the Smocker instance
mkdir -p /opt/smocker && cd /opt/smocker
wget -P /tmp https://github.com/smocker-dev/smocker/releases/latest/download/smocker.tar.gz
tar xf /tmp/smocker.tar.gz
nohup ./smocker -mock-server-listen-port=8080 -config-listen-port=8081 &

Healthcheck

curl localhost:8081/version

User Interface

Smocker exposes a configuration user interface. You can access it in your web browser on http://localhost:8081/.

Usage

Smocker exposes two ports:

• 8080 is the mock server port. It will expose the routes you register through the configuration port
• 8081 is the configuration port. It's the port you will use to register new mocks. This port also exposes a user interface.

Hello, World!

To register a mock, you can use the YAML and the JSON formats. A basic mock might look like this:

# helloworld.yml
# This mock register two routes: GET /hello/world and GET /foo/bar
- request:
    # Note: the method could be omitted because GET is the default
    method: GET
    path: /hello/world
  response:
    # Note: the status could be omitted because 200 is the default
    status: 200
    headers:
      Content-Type: application/json
    body: >
      {
        "hello": "Hello, World!"
      }

- request:
    method: GET
    path: /foo/bar
  response:
    status: 204

You can then register it to the configuration server with the following command:

curl -XPOST \
  --header "Content-Type: application/x-yaml" \
  --data-binary "@helloworld.yml" \
  localhost:8081/mocks

After your mock is registered, you can query the mock server on the specified route, so that it returns the expected response to you:

$ curl -i localhost:8080/hello/world
HTTP/1.1 200 OK
Content-Type: application/json
Date: Thu, 05 Sep 2019 15:49:32 GMT
Content-Length: 31

{
  "hello": "Hello, World!"
}

To cleanup the mock server without restarting it, you can execute the following command:

curl -XPOST localhost:8081/reset

For more advanced usage, please read the project's documentation.

Mock format schema

A JSON Schema describing the mock format lives at docs/mock.schema.json. It is generated from and kept in sync with the Go types (server/types): the example mocks under tests/data are validated against it in CI, so it stays accurate. The documentation references this file as the canonical schema.

Editors can use it for autocompletion and validation. With the YAML language server (VS Code, Neovim, …), add this line at the top of a mocks file:

# yaml-language-server: $schema=https://raw.githubusercontent.com/smocker-dev/smocker/main/docs/mock.schema.json
- request:
    path: /hello
  response:
    body: '{"message": "Hello, World!"}'

Development

Backend

The backend is written in Go. You can use the following commands to manage the development lifecycle:

• make start: start the backend in development mode, with live reload
• make build, make VERSION=xxx build: compile the code and generate a binary
• make lint: run static analysis on the code
• make format: automatically format the backend code
• make test: execute unit tests
• make test-integration: execute integration tests

Frontend

The frontend is written with TypeScript and React, bundled with Vite. You can use the following commands to manage the development lifecycle:

• npm install: install the dependencies
• npm run dev: start the Vite dev server with hot reload. It proxies the admin API to the backend, so run make start alongside it (override the target with SMOCKER_DEV_PROXY if the backend is elsewhere)
• npm run build: generate the transpiled and minified files and assets
• npm run lint: run static analysis on the code
• npm run format: automatically format the frontend code
• npm test: execute unit tests
• npm run test:watch: execute unit tests, with live reload

Docker

The application can be packaged as a standalone Docker image. You can use the following commands to manage the development lifecycle:

• make build-docker, make VERSION=xxx build-docker: build the application as a Docker image
• make start-docker, make VERSION=xxx start-docker: run a Smocker Docker image

Caddy

If you need to test Smocker with a base path, you can use the Caddyfile provided in the repository (Caddy v2):

• make start-release, make VERSION=xxx start-release: create a released version of Smocker and launch it with /smocker/ as base path
• make start-caddy: start Caddy to make Smocker accessible at http://localhost:8082/smocker/

HTTPS

If you need to test Smocker with HTTPS enabled, the easiest way is to generate a locally signed certificate with mkcert:

# Install the local certificate authority
mkcert -install

# Create a certificate for localhost
mkcert -cert-file /tmp/cert.pem -key-file /tmp/key.pem localhost

Then, start Smocker with TLS enabled, using your generated certificate:

./smocker -mock-server-listen-port=44300 -config-listen-port=44301 -tls-enable -tls-cert-file=/tmp/cert.pem -tls-private-key-file=/tmp/key.pem

Authors

• Thibaut Rousseau
• Gwendal Leclerc

Contributors

• Amanda Yoshiizumi (mandyellow): thank you for your awesome logo!