dotenv

dotenv: env file loading

dotenv: loads a KEY=value file into two places at once: the {{.VAR}} / {{.VAR:-default}} template context (for args, environment, startup) and the child's environment. The file is re-read at every service start, so a restart picks up rotated values without a daemon reload.

Config

processes:
  - name: app
    command: /bin/sh
    args: ["-c", "test {{.PORT:-8080}} = 9090 && test \"$API_TOKEN\" = s3cr3t && sleep 300 || exit 9"]
    dotenv: .env
    on-failure: shutdown

With the .env file next to it containing:

PORT=9090
API_TOKEN=s3cr3t

A relative dotenv: path resolves against gopherd's working directory — handy for local runs; prefer an absolute path in containers.

• {{.PORT:-8080}} expands from the dotenv value (9090); with PORT absent it would fall back to 8080.
• API_TOKEN lands in the child environment directly — no template needed.
• Precedence (highest last): OS env (only with pass-env: true) < dotenv < per-process environment:. remove-env strips keys after the merge.
• Format: one KEY=value per line, # comments and blank lines ignored, optional single/double quotes (double quotes process \n, \t, \").

Safety checks

The file must be a regular file, not world-writable, and owned by root or gopherd's own uid — otherwise the service refuses to start. Symlinks (the file itself or a parent directory) are refused by default; set dotenv-follow: true to permit them, confined to the file's directory. That is required for K8s secret mounts (key -> ..data/key) and paths under system symlinks like /var/run -> /run — same rules as the {{file}} template's follow modifier (see file-inclusion).

Expected behavior

• Both assertions in the config pass, so app reaches running: the template expanded from the dotenv file and the child env got the token.
• Pointing dotenv: at a symlink fails the start with a clear error unless dotenv-follow: true is set.

Test

Run level. One test runs the example against the checked-in .env and asserts the service runs (both template and env checks passed). The other points dotenv: at a symlink and asserts the start is refused, then succeeds with dotenv-follow: true. SIGTERM yields a clean exit 0.

go test ./documentation/dotenv/ -v