Function Lifecycle Management

ContainerPub provides comprehensive lifecycle management for serverless functions, from initialization through deployment, versioning, and eventual deletion.

Overview

The function lifecycle consists of several stages:

• Initialization - Create function record and get UUID
• Deployment - Upload code and build container
• Active - Function is running and accepting invocations
• Versioning - Track deployment history
• Rollback - Restore previous versions
• Deletion - Scheduled cleanup with grace period

Function Initialization

Before deploying a function, you must initialize it to receive a UUID.

POST /api/functions/init

Purpose: Creates a function record in the database with status init and generates a unique UUID.

Request:

{
  "name": "my_function",
  "skip_signing": false  // Optional, default: false
}

Response (New Function):

{
  "message": "Function initialized successfully",
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "name": "my_function",
  "status": "init",
  "skip_signing": false,
  "created_at": "2025-02-21T00:00:00Z"
}

Response (Existing Function):

{
  "message": "Function already exists",
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "name": "my_function",
  "status": "active",
  "skip_signing": false,
  "deployment_version": 3,
  "created_at": "2025-01-15T00:00:00Z",
  "already_exists": true
}

Key Points:

• Function name must be unique per user
• Returns existing function if name already exists
• UUID is used for all subsequent operations
• skip_signing controls whether API key signatures are required

Deployment

After initialization, deploy your function code.

POST /api/functions/deploy

Request:

• function_id - UUID from init endpoint
• archive - Function code archive (tar.gz)
• env - Environment variables (JSON, optional)

Status Transitions:

init → building → active

For redeployments:

active → building → active (new version)

Versioning & Deployment History

Every deployment creates a new version. View complete deployment history with pagination.

GET /api/functions/:id/deployments

Query Parameters:

• page - Page number (default: 1)
• per_page - Results per page (default: 20, max: 100)

Response:

{
  "function_uuid": "550e8400-e29b-41d4-a716-446655440000",
  "function_name": "my-function",
  "function_status": "active",
  "page": 1,
  "per_page": 20,
  "count": 5,
  "total_pages": 1,
  "has_next": false,
  "deployments": [
    {
      "uuid": "deployment-uuid-3",
      "version": 3,
      "image_tag": "registry/my-function:v3",
      "s3_key": "functions/550e8400/v3.tar.gz",
      "status": "active",
      "is_active": true,
      "created_at": "2025-02-21T10:00:00Z",
      "deployed_at": "2025-02-21T10:01:30Z"
    },
    {
      "uuid": "deployment-uuid-2",
      "version": 2,
      "image_tag": "registry/my-function:v2",
      "s3_key": "functions/550e8400/v2.tar.gz",
      "status": "inactive",
      "is_active": false,
      "created_at": "2025-02-20T10:00:00Z",
      "deployed_at": "2025-02-20T10:01:15Z"
    }
  ]
}

Features:

• Ordered by version (newest first)
• Shows active vs inactive deployments
• Includes S3 storage keys
• Deployment timestamps

Rollback

Restore a previous deployment version.

POST /api/functions/:id/rollback

Request:

{
  "version": 2
}

Response:

{
  "message": "Function rolled back successfully",
  "function": {
    "uuid": "550e8400-e29b-41d4-a716-446655440000",
    "name": "my-function",
    "status": "active",
    "active_version": 2
  }
}

What Happens:

• Previous active deployment marked as inactive
• Specified version marked as active
• Function container restarted with rolled-back version
• All invocations use the restored version

Use Cases:

• Revert breaking changes
• Restore stable version after failed deployment
• A/B testing different versions
• Emergency rollback

Deletion Management

Functions scheduled for deletion enter a grace period before permanent removal.

Pending Deletions

View all functions scheduled for deletion.

GET /api/functions/pending-deletions

Response:

{
  "pending_deletions": [
    {
      "id": "pending-deletion-uuid",
      "function_uuid": "550e8400-e29b-41d4-a716-446655440000",
      "function_name": "my-function",
      "function_status": "pending_deletion",
      "image_tag": "registry/my-function:v3",
      "reason": "user_requested",
      "deletion_date": "2025-03-01T00:00:00Z",
      "days_remaining": 7,
      "scheduled_at": "2025-02-21T10:30:00Z"
    }
  ],
  "count": 1
}

Deletion Reasons:

• user_requested - User initiated deletion
• stale_function - Inactive for extended period
• quota_exceeded - Account quota management

Check Deletion Status

Get deletion status for a specific function.

GET /api/functions/:uuid/deletion-status

Response:

{
  "function_uuid": "550e8400-e29b-41d4-a716-446655440000",
  "function_name": "my-function",
  "has_pending_deletion": true,
  "deletion_info": {
    "id": "pending-deletion-uuid",
    "image_tag": "registry/my-function:v3",
    "reason": "user_requested",
    "deletion_date": "2025-03-01T00:00:00Z",
    "days_remaining": 7,
    "scheduled_at": "2025-02-21T10:30:00Z"
  }
}

Cancel Deletion

Cancel a pending deletion and restore function to active status.

POST /api/functions/:uuid/cancel-deletion

Response:

{
  "success": true,
  "message": "Deletion cancelled successfully",
  "function": {
    "uuid": "550e8400-e29b-41d4-a716-446655440000",
    "name": "my-function",
    "status": "active"
  }
}

What Happens:

• All pending deletion records marked as cancelled
• Function status restored to active
• Function remains operational
• Deletion can be rescheduled if needed

Status Lifecycle

┌─────────────────────────────────────────────┐
│                                             │
│  init → building → active                   │
│           ↑         ↓                       │
│           └─────────┘ (redeploy)            │
│                     ↓                       │
│              pending_deletion               │
│                     ↓                       │
│                 deleted                     │
│                                             │
└─────────────────────────────────────────────┘

Status Definitions:

• init - Function initialized, awaiting first deployment
• building - Container image being built
• active - Function deployed and accepting invocations
• pending_deletion - Scheduled for deletion
• deleted - Permanently removed

Best Practices

Initialization

• Initialize functions before deployment
• Use descriptive, unique function names
• Store function UUID securely in your deployment config

Versioning

• Keep deployment history for rollback capability
• Test new versions before promoting to production
• Document version changes for team awareness

Rollback Strategy

• Monitor new deployments closely
• Have rollback plan ready for critical functions
• Test rollback procedure in staging environment

Deletion Management

• Review pending deletions regularly
• Cancel accidental deletions promptly
• Use grace period to backup important data

Integration Example

// 1. Initialize function
final initResponse = await apiClient.initFunction('my-function');
final functionId = initResponse['id'];

// 2. Deploy function
await apiClient.deployFunction(
  functionId: functionId,
  archive: archiveFile,
  env: {'KEY': 'value'},
);

// 3. View deployment history
final deployments = await apiClient.getDeployments(
  functionId: functionId,
  page: 1,
  perPage: 10,
);

// 4. Rollback if needed
await apiClient.rollbackFunction(
  functionId: functionId,
  version: 2,
);

// 5. Check deletion status
final deletionStatus = await apiClient.getDeletionStatus(
  functionId: functionId,
);

// 6. Cancel deletion if needed
if (deletionStatus['has_pending_deletion']) {
  await apiClient.cancelDeletion(functionId: functionId);
}

Next Steps

• Read API Reference for complete endpoint documentation
• Check Function Execution for invocation details
• Review Statistics & Monitoring for performance tracking