error installing dpl about dpl HOT 4 CLOSED

Your screenshot shows that the current Ruby version is 2.4.5. That's the ${travis_internal_ruby}. You might need to set up your deploy step in a separate step kinda like GitLab users do in their .gitlab.yaml:

deploy_staging:
  stage: deploy
  type: deploy
  image: ruby:latest
  script:
  # workaround https://github.com/travis-ci/dpl/issues/1247
  - gem install dpl && gem install faraday -v 1.8.0
  - dpl --provider=heroku --app=$HEROKU_APP_NAME --api-key=$HEROKU_PRODUCTION_API_KEY
  except:
  - schedules
  only:
  - merge_requests

You'll have to translate that to the equivalent in Travis config, though, obviously.

from dpl.

Thanks. My new file .travis.yml

language: java
jdk:
  - openjdk8

env:
  - HEROKU_APP_NAME = [heroku_app_name]

before_install:
  - chmod +x mvnw
script:
  - mvn clean verify
deploy:
  provider: script
  skip_cleanup: true
  script:
    - rvm use $TRAVIS_RUBY_VERSION do script.rb
    - gem install dpl && gem install faraday -v 1.8.0
    - dpl --provider=heroku --app=$HEROKU_APP_NAME --api-key=$HEROKU_PRODUCTION_API_KEY
  on:
    repo: [my_repo_github]
    branch: main

but now I have a new problem

I search in .travis.yml but I don't see any 'ruby'

from dpl.

I don't see how that could be happening, either.

Try replacing $TRAVIS_RUBY_VERSION with 2.7.0 -- the key problem is that Travis' ruby is too old -- that's the error in your original post.

from dpl.

Thanks it works.
I change this line

rvm use $TRAVIS_RUBY_VERSION do script.rb

- rvm use $TRAVIS_RUBY_VERSION  use 2.7.0

from dpl.