cloud-interview-app

README

cloud-interview-app

This repo contains a microservice application for use during various interviews at Syndio. Instructions for the interview will be provided separately.

Architecture

A basic gateway API proxies requests to a RESTful JSON api serving employee data from Redis and PostgreSQL. The results are cached in Redis after being retrieved from PostgreSQL.

|-----------|      |---------------|
|  GATEWAY  | -->  | EMPLOYEES API | + REDIS/POSTGRES
|-----------|      |---------------|

Repo Layout

Basic configuration and instructions:

├── Dockerfile
├── LICENSE
├── README.md
├── compose.yaml

The employees microservice:

├── employees
│   ├── cmd
│   │   └── employeesapi
│   │       └── employeesapi.go   <- the api service
│   └── internal
│       ├── employeesdb
│       │   ├── employeesdb.go    <- the database client
│       │   └── init.sql
│       └── employeeshttp
│           └── employeeshttp.go  <- the http handlers

The gateway microservice:

├── gateway
│   └── cmd
│       └── gateway
│           └── gateway.go        <- the gateway service

Go dependency information:

├── go.mod
└── go.sum

Setup

The project is configured for use with Docker Compose. You'll need to have the Docker daemon running, e.g. from Docker for Mac for macOS.

1. Get the repo locally git clone git@github.com:syndio/cloud-interview-app.git
2. Run docker compose up -d --build to start everything in the background.
3. When you're done, run docker compose down to shut down running containers.

Access

You can view logs for all services by running:

docker compose logs -f gateway employeesapi

You can view logs for all supporting services by running:

docker compose logs -f postgres redis

You can connect to and query the employees database by running:

> docker compose exec postgres psql -U dev -d employees
psql (13.4 (Debian 13.4-1.pgdg110+1))
Type "help" for help.

employees=# select * from employees;
 id | title
----+-------
  8 | foo
 10 | bar
(2 rows)

You can connect to and query the redis cache by running:

> docker compose exec redis redis-cli
127.0.0.1:6379> KEYS *
1) "employees"
127.0.0.1:6379> GET employees
"[{\"id\":8,\"title\":\"foo\"},{\"id\":10,\"title\":\"bar\"}]"

Example Usage

The examples provided here make use of httpie.

Create an Employee

> http POST localhost:6540/employees title=engineer
HTTP/1.1 201 Created
Content-Length: 27
Content-Type: application/json
Date: Tue, 28 Sep 2021 15:17:14 GMT

{
    "id": 5,
    "title": "engineer"
}

List all Employees

> http localhost:6540/employees
HTTP/1.1 200 OK
Content-Length: 56
Content-Type: application/json
Date: Tue, 28 Sep 2021 15:23:36 GMT

[
    {
        "id": 5,
        "title": "engineer"
    },
    {
        "id": 6,
        "title": "manager"
    }
]

Delete an Employee

> http DELETE localhost:6540/employees/5
HTTP/1.1 204 No Content
Date: Tue, 28 Sep 2021 15:24:15 GMT