harness-drone/docs/build/env.md

Variables

Drone injects the following namespaced environment variables into every build:

• DRONE=true
• DRONE_REPO - repository name for the current build
• DRONE_BRANCH - branch name for the current build
• DRONE_COMMIT - git sha for the current build
• DRONE_DIR - working directory for the current build
• DRONE_BUILD_NUMBER - build number for the current build
• DRONE_PULL_REQUEST - pull request number fo the current build
• DRONE_JOB_NUMBER - job number for the current build
• DRONE_TAG - tag name for the current build

Drone also injects CI_ prefixed variables for compatibility with other systems:

• CI=true
• CI_NAME=drone
• CI_REPO - repository name of the current build
• CI_BRANCH - branch name for the current build
• CI_COMMIT - git sha for the current build
• CI_BUILD_NUMBER - build number for the current build
• CI_PULL_REQUEST - pull request number fo the current build
• CI_JOB_NUMBER - job number for the current build
• CI_BUILD_DIR - working directory for the current build
• CI_BUILD_URL - url for the current build
• CI_TAG - tag name for the current build

Substitution

A subset of variables may be substituted directly into the Yaml at runtime using the $$ notation:

• $$BUILD_NUMBER build number for the current build
• $$COMMIT git sha for the current build, long format
• $$BRANCH git branch for the current build
• $$BUILD_NUMBER build number for the current build
• $$TAG tag name

This is useful when you need to dynamically configure your plugin based on the current build. For example, we can alter an artifact name to include the branch:

publish:
  s3:
    source: ./foo.tar.gz
    target: ./foo-$$BRANCH.tar.gz

Operations

A subset of bash string substitution operations are emulated:

• $$param parameter substitution
• $${param} parameter substitution (same as above)
• "$$param" parameter substitution with escaping
• $${param:pos} parameter substition with substring
• $${param:pos:len} parameter substition with substring
• $${param=default} parameter substition with default
• $${param##prefix} parameter substition with prefix removal
• $${param%%suffix} parameter substition with suffix removal
• $${param/old/new} parameter substition with find and replace