Spring Boot: Heroku

Tips for running with Spring Boot applications on Heroku

Error: `failed to bind to $PORT within 90 seconds`

Symptom:

2019-11-21T00:07:44.777985+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 90 seconds of launch
2019-11-21T00:07:44.778119+00:00 heroku[web.1]: Stopping process with SIGKILL
2019-11-21T00:07:44.954279+00:00 heroku[web.1]: State changed from starting to crashed
2019-11-21T00:07:44.939776+00:00 heroku[web.1]: Process exited with status 137

Solution:

In src/main/resources/application.properties you need:

server.port=${PORT:8080}

Reason: Heroku doesn’t always run your webapp on port 8080. It runs many webapps on the same server, on many different ports. Your webapp must run on the port Heroku tells it to run on, which is specified in the PORT environment variable. If it doesn’t start up there, Heroku kills it off.

Related topics:

Spring Boot: —A Java web application framework
Spring Boot: Actuator—Checking the endpoint mappings, health or other info about your Spring Boot app
Spring Boot: Application Properties—Defining the application.properties
Spring Boot: ControllerAdvice—A place to factor out common ExceptionHandler, ModelAttribute and InitBinder code across multiple controllers
Spring Boot: CSV—Downloading and Uploading CSV files with Spring Boot
Spring Boot: Database Migrations—When you need to make a change to your database schema for an app in progress
Spring Boot: Heroku—Tips for running with Spring Boot applications on Heroku
Spring Boot: Logging—How to write information to the log in Spring Boot
Spring Boot: OAuth—How to implement OAuth for authentication in Spring Boot
Spring Boot: POST and CSRF—If you get 403 forbidden messages when using POST
Spring Boot: Postgres—Using Spring Boot with Postgres
Spring Boot: RestTemplate—When you need to access other APIs from the backend of your Spring Boot Application
Spring Boot: Secrets—Ways of keepings database credentials and OAuth client secrets out of Github
Spring Boot: Security—Authentication, Authorization and other Security issues
Spring Boot: Sessions—How to make the stateless HTTP protocol stateful
Spring Boot: SQL—Working with SQL and Databases in Spring Boot
Spring Boot: VS Code—Suggested VS Code extensions for working with Spring Boot