Heroku Postgres Helper

A Java library to help with Heroku Postgres specific logic, enabling fast release phases without code duplication.

Usage

build.gradle:

// If using connection string in build script:
buildscript {
    repositories {
        maven { url 'https://jitpack.io' }
    }
    dependencies {
        classpath 'com.github.vic-cw:heroku-postgres-helper:0.1.0'
    }
}
import com.github.viccw.herokupostgreshelper.HerokuPostgresHelper;

// Use connection string in build script:
flyway {
    url = HerokuPostgresHelper.getDatabaseJdbcConnectionString()
    driver = 'org.postgresql.Driver'
}

// If using connection string inside application logic:
repositories {
    maven { url 'https://jitpack.io' }
}

dependencies {
    compile group: 'com.github.vic-cw', name: 'heroku-postgres-helper', version: '0.1.0'
}

Java application code:

import com.github.viccw.herokupostgreshelper.HerokuPostgresHelper;

...

String databaseConnectionString = HerokuPostgresHelper.getDatabaseJdbcConnectionString();

Why a need for this logic?

Heroku Postgres provides the database details through the DATABASE_URL environment variable in the following pattern: postgres://username:password@host:port/databaseName.

Conversely, any technology reliant on JDBC expects a connection string in the following format: jdbc:postgresql://host:port/databaseName?user=username&password=password

Thus logic is required to translate the former into the latter.

Why a need for a library?

If using Gradle, or another build tool with the same restriction, sharing code between the build script and the application is difficult.

There is a need for a library if using a database migration system, such as FlywayDB, to avoid code duplication between build script and application code.

Without such a library, options are:

1. to copy paste this logic once in build script, and once in application code
2. to place this logic inside a buildSrc folder at the root of Gradle project

Why not simply place logic in buildSrc?

It turns out that Heroku is very slow at compiling buildSrc in a release phase, typically taking 1 to 2 minutes to compile just 5 lines of code.

Using a library such as this one enables to speed up release commands without duplicating any code.