Golang REST API application with Redis, PostgreSQL and in-app cache

Stack

• Go 1.18
• Redis
• PostgreSQL
• Docker

Development

1. The Web Service reached under the path /film/:title

2. The Application has to realize the following logic:

   a. An HTTP request is sent against the endpoint /film/:title.

   b. The application requests data stored in a database (PostgreSQL).

   b. The request-payload contains a JSON object with movie title information.

   c. The application caches data: - 15 seconds in application memory, - 30 seconds in Redis store.

General description

Docker, docker-compose, curl should be preinstalled.

Used Docker version 20.10.17 and docker-compose version 1.29.0.

Golang REST API application, stores data in PostgreSQL and two level cache (application memory, Redis) - on get requests application checks the application memory and then the Redis before request the data in PostgreSQL.

Application returns JSON in format:

{film:{"film_id" : integer, "title" : "character varying", "description": "text", "release_year" : integer, "language_id":smallint, "rental_rate":numeric, "replacement_cost":numeric, "rating":"mpaa_rating", "last_update": "timestamp without time zone", "special-features":"text[]", "full-text":"txvector"}}

Directories:

controllers - endpoints and acts on models.

models - PostgreSQL, Redis, application cache data structures and acts on data.

How to deploy

The Docker image can be rebuilt by

docker build -t go-pg-redis-memc .

Deploy application:

docker-compose up --build 

It will run go, redis, containers and available as:

http://127.0.0.1:8080/film/:title

Stop application:

docker-compose down

Testing

Makefile - contains curl commands to send.

make test-get - send GET requests to retrieve data.

Example:

$ make test-get

Additional

1. The Web Service has response time log reached under the path /log .

2. The time log is stored in the database PostgreSQL.

3. The log records the last response time for a specific request in milliseconds.

4. Application response time log returns JSON in format:

{ResponseTimeLog:[{"Id" : integer, "Request" : "text", "TimeDb" : numeric, "TimeRedis" : numeric, "TimeMemory" : numeric,}]}

Configuration

1. Demo DB deployed on the cloud services https://www.elephantsql.com/ .

2. Demo dataset https://www.postgresqltutorial.com/postgresql-sample-database/ .

3. Http-port listening "8080" by default.

4. You can change cofiguration params in models/config.go file.