Loading Environment Variables via dotenv-java
This post documents the usage of dotenv-java library which aids in loading Environment Variables which are often using to store confidential configuration values such as API keys, Database passwords etc., instead of directly adding these values in the codebase.
This library is available in both Java and Kotlin flavours and also supports usage in Android.
We are consciously avoiding using System.getenv(...) to do the same.
Minimum Software Requirements
- Java 8 or higher
- dotenv-java library (Maven/Gradle)
Sample Project
Spring Boot Minimal Web App is the sample Spring Boot web application i've used to illustrate the usage of the aforementioned tool.
Navigate to http://localhost:8080/ to discover the application URLs.
Dependencies
This implementation has one dependency, dotenv-java. The maven/gradle dependencies of the same is mentioned below.
dotenv-java
<!-- https://mvnrepository.com/artifact/io.github.cdimascio/dotenv-java -->
<dependency>
<groupId>io.github.cdimascio</groupId>
<artifactId>dotenv-java</artifactId>
<version>2.2.0</version>
</dependency>
or
// https://mvnrepository.com/artifact/io.github.cdimascio/dotenv-java
implementation group: 'io.github.cdimascio', name: 'dotenv-java', version: '2.2.0'
Basic Usage
Create a .env file in the root of your project with the following structure.
# formatted as key=value
MY_ENV_VAR1=some_value
MY_ENV_VAR2=some_value
Initialize the library and get the environment variables as per the need.
Dotenv dotenv = Dotenv.load();
dotenv.get("MY_ENV_VAR1")
Notes
To edit the .env file you could simply navigate to project's directory and open the file by a text editor.
Eclipse IDE by default doesn't show dot files in the Project Explorer tab. To enable this functionality follow the below mentioned steps.
Project Explorer -> View Menu -> Filters -> uncheck .* resources
Links
- Queries regarding best practices, multi-line values, multiple .env files, usage in PRODUCTION environment and other frequently asked questions have been addressed by the authors of the project here.
