Prime

An OTP application. The prime server is implemented as a gen_server.

The server works like this:

• When starting up, the prime_server initializes and waits for requests.
• Users call us using gen_server:call (sync) or gen_server:cast (async) that sends a request to generate uniformly distributed pseudorandom numbers(PRNs) according to the uniform distribution function. In addition, PRNs are generated at a frequency of 3000 numbers per second (by default) and are queued in Redis (List data structure).

    F(x) = x, 2 =< x =< N
    where
        N is the upper limit of PRNs

• As soon as the generator is started, the filter starts taking PRNs from the queue, checking that numbers is prime and adding prime numbers in Redis (Set data structure).

Parameters:

• N is the upper limit of pseudorandom numbers (aka PrnUpperLimit);
• RedisHost, RedisPort, RedisDB are connection parameters to Redis;
• QueueKey is the queue key used by the generator in Redis;
• ResultSetKey is the set key used by the filter in Redis.

Prerequisites

The installation of prerequisites for ArchLinux is shown.

• Erlang/OTP:

    $ sudo pacman -S erlang

• Rebar3 build tool:

    $ yay -S rebar3

• Redis db:

    $ sudo pacman -S redis

Build

• If needed, remove the _build directory to remove all compilation artifacts

    $ cd /target/prime
    $ rm -rf _build

• Update the package index

    $ rebar3 update

• Upgrade dependencies

    $ rebar3 upgrade --all

• Compile the needed dependencies and the project’s apps’ .app.src and .erl files

    $ rebar3 compile

• If needed, build release tarball
  Tarball target directory _build/prod/rel/prime/prime-0.1.0.tar.gz

    $ rebar3 as prod tar

Usage

• Start Redis in the background by running

    $ redis-server &

• Start an interactive shell and use Prime API

  For development use only

    $ rebar3 shell

For production use

    $ mkdir prime
    $ mv prime-0.1.0.tar.gz prime/
    $ cd prime
    $ tar -zxvf prime-0.1.0.tar.gz
    $ bin/prime console

Prime API:

    {ok, Prime} = prime:start_link().
    prime:generate(Prime).
    prime:cancel(Prime).
    prime:get_res(Prime).
    prime:stop(Prime).

Testing

The Redis Server should be started.

Run EUnit tests on project apps

    $ rebar3 eunit

License

Prime was created by Denis Khorkin. It is licensed under the terms of the BSD-3-Clause license.

Credits

• Denis Khorkin