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Prerequisites:

• docker-ce
• docker-compose

Alternatively please check the docker_install.sh script (has been tested on the Debian Stretch and Jessie).

Initial setup:

Make sure there's no app on your host currently bound to the tcp port 8888 or 5432.

Change to the ratestask_sre directory and run the following command:

$ cd ratestask_sre
$ docker-compose up --build

It will build ratestask_app and ratestask_db containers and start them for you.

Once the containers are running, please navigate your browser to:

• http://127.0.0.1:8888/get - for the GET request
• http://127.0.0.1:8888/put - for the POST request

Example POST:

$ curl -sX POST -d date_from=2016-01-09 -d date_to=2016-01-19 -d origin_code=CNGGZ -d destination_code=eetll -d price=1234 http://127.0.0.1:8888/put
{
  "success": true
}

Example GET:

$ curl -s 'http://127.0.0.1:8888/get?date_from=2016-01-10&date_to=2016-01-11&origin=cnggz&destination=eetll'
[
  {
    "average_price": "1187",
    "day": "2016-01-10"
  },
  {
    "average_price": "1186",
    "day": "2016-01-11"
  }
]

Currently benchmarks on the localhost show ~252 req/s. Such stats in my opinion are totally acceptable.

Notes:

Currently prices table allow duplicate records, which perhaps is a design flaw. I would rather alter the table schema and add the primary key based on the orig_code, dest_code and day columns:

ALTER TABLE prices ADD PRIMARY KEY (orig_code, dest_code, day);

This way INSERT query could be changed to the following and benefit from the UPSERT (UPdate or inSERT):

INSERT INTO prices (orig_code, dest_code, day, price)
VALUES %s ON CONFLICT (orig_code, dest_code, day) DO UPDATE
SET (orig_code, dest_code, day) = '(EXCLUDED.orig_code, EXCLUDED.dest_code, EXCLUDED.day);