Get environment variables exposed by CI services.

Adapted from codecov-node.

$ npm install --save env-ci

import envCi from "env-ci";

const {
  name,
  service,
  isCi,
  branch,
  commit,
  tag,
  build,
  buildUrl,
  job,
  jobUrl,
  isPr,
  pr,
  prBranch,
  slug,
  root,
} = envCi();

if (isCI) {
  console.log(`Building repo ${slug} on ${name} service`);

  if (isPr) {
    console.log(
      `Building Pull Request #${pr} originating from branch ${prBranch} and targeting branch ${branch}`,
    );
  } else {
    console.log(`Building branch ${branch}`);
  }

  if (service === "travis") {
    // Do something specific to Travis CI
  }
}

Note: Some variables can be detected only on certain CI services. See Supported CI.

Note: The pr and prBranch properties are only available for builds triggered when a Pull Request is opened/updated and not on builds triggered by a push on a branch even if that branch happens to be the branch from which the Pull Request originated.

⚠️ See Caveats

Note: Unsupported properties will always be undefined. For example if a Ci services doesn't support triggering builds when a Pull Request is opened/updated, isPr will be undefined.

Note: If none of the above CI services is detected, commit and branch are determined based on the local Git repository, and isCi is determined based on the CI environment variable.

Type: Object

Type: Object
Default: process.env

The object to read environment variables from.

Type: String
Default: process.cwd()

The current working directory in which to execute git commands used to determine the commit and branch Result properties in case no supported CI is detected.

Type: Object

Environment variables values exposed by the CI service.

AWS CodeBuild doesn't provide an environment variable to determine the current Git branch being built. In addition, it clones the repository in a detached head state so the branch cannot be determined with git rev-parse --abbrev-ref HEAD. To work around this limitation, env-ci look for the remote branches having the same HEAD as the local detached HEAD to determine the branch from which the detached HEAD was created. In the rare case where there is multiple remote branches with the same HEAD as the local detached HEAD, env-ci will arbitrarily pick the first one. This can lead to an inaccurate branch value in such circumstances.

For builds triggered when a Pull Request is opened/updated, CircleCI doesn't provide an environment variable indicating the target branch. Therefore, in the case of Pull Request builds, env-ci will not be able to determine the branch property. However prBranch will be set.

See feature request.

For builds triggered when a Pull Request is opened/updated, Cloudflare Pages will re-use the branch variable for the originating branch and not provide a target. Therefore env-ci will not be able to determine the prBranch property however branch will always be set.

Triggering build when a Pull Request is opened/updated is supported only via the ghprb-plugin and gitlab-plugin. Therefore env-ci will set isPr, pr and prBranch and define branch with the Pull Request target branch only if one those plugin is used.

For builds triggered when a Pull Request is opened/updated, Netlify doesn't provide an environment variable indicating the target branch. Therefore, in the case of Pull Request builds, env-ci will not be able to determine the branch property. However prBranch will be set.

See feature request

For builds triggered when a Pull Request is opened/updated, Sail doesn't provide an environment variable indicating the target branch, and the one for the current branch is set to pull/<PR number> independently of the the branch name from which the Pull Request originated. Therefore, in the case of Pull Request builds, env-ci will not be able to determine the branch and prBranch properties.

For builds triggered when a Pull Request is opened/updated, Semaphore 1.0 doesn't provide an environment variable indicating the target branch. Therefore, in the case of Pull Request builds, env-ci will not be able to determine the branch property. However prBranch will be set. On Semaphore 2.0 the branch and prBranch properties will work as expected.

The property tag is only available on Semaphore 2.0.

For builds triggered when a Pull Request is opened/updated, Screwdriver sets the env.GIT_BRANCH as head:pr branch type (Example:origin/refs/pull/1/head:pr) while at commit level (non PR) it does set it with the actual branch (Example: origin/main).