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Automatic Configuration via Environment Variables

Since version v3.12.0, Snaper can start without requiring manual initialization (snaper init) or a pre-existing configuration file. If no configuration file is found, Snaper will automatically attempt to generate one based on a set of environment variables.

Why this change?​

This functionality significantly simplifies the deployment of Snaper in environments where managing configuration files is impractical or impossible:

  • Ephemeral Docker containers (CI/CD, one-off jobs, etc.)
  • Orchestrators like Kubernetes (using Secret and ConfigMap)
  • Shared server environments or shared hosting (execution via cron)
  • Automation scenarios where initialization must be fully scripted

How it works​

  • At startup, if the Snaper configuration file does not exist, it will be automatically generated from the environment variables (listed below).
  • If all required variables are present, execution proceeds normally, and the configuration file is saved for future runs.
  • If some required variables are missing, Snaper stops and indicates which variables need to be added.

Supported Environment Variables​

Required variables:

  • AWS_ACCESS_KEY_ID
  • AWS_SECRET_ACCESS_KEY
  • DATASHELTER_BUCKET

Optional recommended variables:

  • SNAPER_ENCRYPTION_KEY: encryption key (automatically persisted)
  • SNAPER_MANAGE_CRONTABS: to disable automatic crontab management (false, 0)

Usage Examples​

1. Docker​

One-off execution:

docker run --rm \
  -e AWS_ACCESS_KEY_ID=AKIA... \
  -e AWS_SECRET_ACCESS_KEY=secret \
  -e DATASHELTER_BUCKET=my-bucket \
  -e SNAPER_ENCRYPTION_KEY=my-encryption-key \
  datashelter/snaper:latest snaper backup

2. Docker Compose​

services:
  snaper:
    image: datashelter/snaper:latest
    environment:
      - AWS_ACCESS_KEY_ID=${AWS_ACCESS_KEY_ID}
      - AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY}
      - DATASHELTER_BUCKET=${DATASHELTER_BUCKET}
      - SNAPER_ENCRYPTION_KEY=${SNAPER_ENCRYPTION_KEY}

3. Kubernetes​

Inject variables via a Secret:

envFrom:
  - secretRef:
      name: snaper-secret

Key Considerations​

  • If a required variable is missing, Snaper displays a clear error with the list of variables to add.
  • If you provide an encryption key (SNAPER_ENCRYPTION_KEY), it will be persisted to disk: ensure the configuration directory is secured.
  • For persistent environments, you can mount a volume to retain the automatically generated configuration file.

Security​

  • Prefer using native secret management systems (Docker secrets, Kubernetes Secrets, etc.) to inject sensitive variables.
  • Avoid exposing keys in source code, images, or logs.