TV and Radio Recording Server

This document will guide you through how to setup and test the server that records internet radio and TV channels. First, you will need to install some dependencies and then run the automated test to verify the installation was successful.

This guide will then explain how to do the manual tests of the application. The application was built on Ubuntu 18.04 using Django and the Django Rest Framework with a SQLite3 database and Celery for the recording threads. You can find pre-recorded example files in the recording_files folder.

Installation

You will first need to setup a pipenv virtual environment before the dependencies can be installed. If you don't have it already, it can be installed running:

$ pip install pipenv

Once you have installed, navigate to the project folder and run:

$ pipenv --python 3.7

Next, you will need to activate the virtual environment and install all the required packages:

$ pipenv shell
$ pipenv update

Aside from the Python packages, you will also need Redis. You can find installation details here. details here.

Running the server

To verify that everything is working, you can start the Django server and the run all the API tests. Make sure you are in the project root folder, and then run:

$ python manage.py runserver

Following that, open up a new terminal window and run the tests:

$ python manage.py test recording.test_views

API

Below are is the API spec for the recording server. You can run these commands to interact with the API and create, read, update or delete your own channels and recordings.

Create a new channel

POST http://127.0.0.1:8000/api/channel/

Here is an example of the POST data that needs to be included.

{
    "channel": {
        "name": "My Channel",
        "keyname": "my-channel",
        "channel_type": "radio",
        "url": "http://www.myradio.com"
    }
}

The keyname must be 10 characters in length. The channel_type can be either radio or tv.

View channel details

GET http://127.0.0.1:8000/api/channel/<channel_id>/

The channel_id is the database primary key of the channel. Data will be returned in the same JSON format as shown above.

Tip: If you navigate to the above address in your browser, you will be provided with a convenient interface to interact with the API.

Update a channel

PUT http://127.0.0.1:8000/api/channel/<channel_id>/

Delete a channel

DELETE http://127.0.0.1:8000/api/channel/<channel_id>/

View a recording

GET http://127.0.0.1:8000/api/recording/<recording_id>/

This gets the details of a single recording with the follow response:

{
    "recording": {
        "channel": 1,
        "start_time": "2020-03-18T13:45:28.556889Z",
        "end_time": "2020-03-18T13:45:55.215624Z",
        "path": "radio/za-jozi-01/za-jozi-01_server01_20200318_134528.aac"
    }
}

The channel value above is the channel ID of the channel on which the recording took place.

View all recordings for a channel

GET http://127.0.0.1:8000/api/recording/<recording_id>/

This gets all of the recordings that were performed on a channel

{
    "recordings": [
        {
            "channel": 6,
            "start_time": "2020-03-18T13:45:28.556889Z",
            "end_time": "2020-03-18T13:45:55.215624Z",
            "path": "radio/za-jozi-01/za-jozi-01_server01_20200318_134528.aac"
        },
        {
            "channel": 6,
            "start_time": "2020-03-18T13:45:48.556046Z",
            "end_time": "2020-03-18T13:46:15.126754Z",
            "path": "radio/za-jozi-01/za-jozi-01_server01_20200318_134548.aac"
        },
        {
            "channel": 6,
            "start_time": "2020-03-18T13:46:08.567983Z",
            "end_time": "2020-03-18T13:46:35.017172Z",
            "path": "radio/za-jozi-01/za-jozi-01_server01_20200318_134608.aac"
        }
    ]
}

Once you have familiarised yourself with the API, you are now ready to use the recording server!

Tip: For convenience, you can also view and update your database using the Django Admin at 127.0.0.1:8000/admin/. Both the username and password are "admin".

Making Recordings

Before we can make recordings, we need to run the Celery worker and Celery Beat schedule that coordinates the recordings. Please make sure all of the commands below are executed within the project root directory in your pipenv environment. We use Redis as the message broker for our tasks. Start Redis by running:

redis-server

Before starting up Celery, make sure that your Django server is running.

Open up a new terminal window and run the following:

celery -A recording worker -l info --concurrency=4

The concurrency is the number of threads that the worker will be able to execute. Please note that this has only been tested on a machine that has 4 CPU threads. As such, the number of recording threads was limited to only 2 channels which each have up to 2 threads each. You may include any number of threads that you have available. Next, start the Beat schedule by running the following in a new terminal window:

celery -A recording beat -l info

If you have any Channels in database, the tasks will automatically start doing the recordings every 20 seconds with a 10 second overlap. You can find your recordings in the recording_files directory.

If you add a new channel, it will start recording on the next beat cycle and will continue until you delete the channel. You may stop the recordings by simply stopping the Celery Beat schedule process.

Contact

Email: flyholmes@gmail.com

GitHub: danielgholmes