How to use environment variables with application.properties in spring boot?

Question

I am trying to configure my application.properties to take the value from the system variables I've set. The problem is that it won't work no matter what I do. I've tried using a custom class configuration with DataSource from this example still no success. All I was able to find on stackoverflow are links pointing to the official docs. Unfortunately that's a dead end since it doesn't say anything and there are no examples for what I'm trying to achieve. I also found examples like spring.datasource.url = ${SPRING_DATASOURCE_URL} and everyone is saying that spring will know how to automatically take the environment variables. Well surprise, it doesn't.

I also found examples like spring.datasource.password = ${SPRING_DATASOURCE_PASSWORD:the_actual_password) or spring.datasource.url = #{SPRING_DATASOURCE_URL:#{'the_actual_url'}} which is totally not what I need and it's pretty useless if you ask me. I mean I could achieve the same thing writing spring.datasource.password = the_actual_password. The whole point is to hide the sensitive data..

Now, this being said I'll leave 2 screenshots with what I have. The reason why I am trying to achieve this is because when I'll push to GitHub I won't have to worry that my credentials or anything will be out in the open for everyone to see.

Here is how my environment variables look like:

Here is how application.properties look like:

Thank you in advance! And in case you have an answer to my question could you also let me know how can I achieve the same thing with environment variable but for the application.jwt properties?

You're looking for _relaxed property binding_. You don't _have_ to map `SPRING_DATASOURCE_URL` to `spring.datasource.url`; Boot does that for you automatically. It also handles overrides/priority automatically. (In general, environment beats properties file because environment is set at each launch.) — chrylis -cautiouslyoptimistic-, Sep 07 '22 at 17:06
Alright, I'll take a look into that. I'll come back if I managed to make it work. Thank you! — Bodea Tudor, Sep 07 '22 at 17:13

score 3 · Answer 1 · answered Sep 07 '22 at 17:37

3

Ok, the solution was pretty... stupid, I suppose, but here it is. The reason why it didn't worked is because the environment variables were defined after IntelliJ first opened as described here. It seems like everything is working fine now.

I managed to achieve the functionality that I wanted.

In other words this:

spring.datasource.url = ${SPRING_DATASOURCE_URL}
spring.datasource.username = ${SPRING_DATASOURCE_USERNAME}
spring.datasource.password = ${SPRING_DATASOURCE_PASSWORD}
spring.datasource.driver-class-name = ${SPRING_DATASOURCE_DRIVERCLASSNAME}

Is now working perfectly.

Thank you for all your help!

answered Sep 07 '22 at 17:37

Bodea Tudor

41
1
7

2

You don't need this, you can ditch this as that works automatically. You can remove those properties from the `application.properties`. – M. Deinum Sep 07 '22 at 18:25
@M.Deinum What do you mean by "ditch this", can you please describe it? – shortduck May 09 '23 at 01:57
When you have an environment variable named `SPRING_DATASOURCE_URL` it will automatically map to `spring.datasource.url` so you don't need all of this. – M. Deinum May 09 '23 at 10:19

Tim · Answer 2 · 2022-09-07T16:58:58.620

-1

Have you used the correct annotations?

Given Properties as such:

root.test = ${TEST.VAR:-Test}

Environment variable like:

TEST.VAR = Something

Configuration class:

@Configuration
@ConfigurationProperties(prefix = "root")
public class Test {
  private String test;

  public String getTest() {
    return test;
  }

  public void setTest(String test) {
    this.test = test;
  }

}

You can use Records by setting @ConfigurationPropertiesScan on your Main class

@SpringBootApplication
@ConfigurationPropertiesScan
public class DemoApplication{...}

Defining Record like so:

@ConfigurationProperties(prefix = "root")
public record Test (String test) {
}

edited Sep 07 '22 at 16:58

answered Sep 07 '22 at 16:51

Tim

561
2
13

I'm sorry but I'm not sure I understand what are you referring to :(. Are you talking about the DataSource custom class? If so please note that it's now what I'm trying to achieve. Basically what I need is whenever I put spring.datasource.username = ${SPRING_DATASROUCE_USERNAME} to take that value from the environment variable. "SPRING_DATASROUCE_USERNAME" being the environment variable that has the value 'user' or something. Thanks for such a quick response! – Bodea Tudor Sep 07 '22 at 16:58
Are the environment variables available to the application? What do you get if you get and print the env var?```String envVar = System.getenv().get("SPRING_DATASROUCE_USERNAME")``` – Tim Sep 07 '22 at 17:06
Oops you might be onto something. It prints null. What does it mean? Is the environment variable not set correctly? – Bodea Tudor Sep 07 '22 at 17:11
Where/How have you try to set it? – Tim Sep 07 '22 at 17:25

How to use environment variables with application.properties in spring boot?

2 Answers2