Back up PostgreSQL to S3

Supported platforms

LinuxmacOS

Prerequisites

• pg_dump
• An S3-compatible bucket
• Database and S3 credentials exposed through environment-backed Dagu secrets

description: Create a PostgreSQL custom-format dump and upload it to S3.
schedule: "0 2 * * *"

params:
  - name: database_name
    default: app
    description: Safe name used in the backup filename
  - name: bucket
    required: true
    description: Destination S3 bucket
  - name: prefix
    default: postgres
    description: Object key prefix

secrets:
  - name: DATABASE_URL
    provider: env
    key: DATABASE_URL
  - name: AWS_ACCESS_KEY_ID
    provider: env
    key: AWS_ACCESS_KEY_ID
  - name: AWS_SECRET_ACCESS_KEY
    provider: env
    key: AWS_SECRET_ACCESS_KEY

defaults:
  retry_policy:
    limit: 2
    interval_sec: 30

steps:
  - id: create_dump
    run: |
      #!/bin/sh
      set -eu
      timestamp="$(date -u +%Y%m%dT%H%M%SZ)"
      file="$DAG_RUN_WORK_DIR/${params.database_name}-${timestamp}.dump"
      key="${params.prefix}/${params.database_name}-${timestamp}.dump"
      pg_dump --format=custom --file="$file" "$DATABASE_URL"
      printf 'file=%s\nkey=%s\n' "$file" "$key" >> "$DAGU_OUTPUT_FILE"
    outputs:
      - name: file
      - name: key

  - id: upload
    depends: [create_dump]
    action: s3.upload
    with:
      bucket: ${params.bucket}
      key: ${steps.create_dump.outputs.key}
      source: ${steps.create_dump.outputs.file}
      content_type: application/octet-stream