jac-scale Reference#

Complete reference for jac-scale, the cloud-native deployment and scaling plugin for Jac.

Installation#

pip install jac-scale

Starting a Server#

Basic Server#

jac start app.jac

Server Options#

Option	Description	Default
`--port`	Server port	8000
`--host`	Bind address	0.0.0.0
`--workers`	Number of workers	1
`--reload`	Hot reload on changes	false
`--scale`	Deploy to Kubernetes	false
`--build` `-b`	Build and push Docker image (with --scale)	false
`--experimental` `-e`	Install from repo instead of PyPI (with --scale)	false
`--target`	Deployment target (kubernetes, aws, gcp)	kubernetes
`--registry`	Image registry (dockerhub, ecr, gcr)	dockerhub

Examples#

# Custom port
jac start app.jac --port 3000

# Multiple workers
jac start app.jac --workers 4

# Development with hot reload
jac start app.jac --reload

# Production
jac start app.jac --host 0.0.0.0 --port 8000 --workers 4

API Endpoints#

Automatic Endpoint Generation#

Each walker becomes an API endpoint:

walker get_users {
    can fetch with Root entry {
        report [];
    }
}

Becomes: POST /walker/get_users

Request Format#

Walker parameters become request body:

walker search {
    has query: str;
    has limit: int = 10;
}

curl -X POST http://localhost:8000/walker/search \
  -H "Content-Type: application/json" \
  -d '{"query": "hello", "limit": 20}'

Response Format#

Walker report values become the response.

@restspec Decorator#

The @restspec decorator customizes how walkers and functions are exposed as REST API endpoints.

Options#

Option	Type	Default	Description
`method`	`HTTPMethod`	`POST`	HTTP method for the endpoint
`path`	`str`	`""` (auto-generated)	Custom URL path for the endpoint
`protocol`	`APIProtocol`	`APIProtocol.HTTP`	Protocol for the endpoint (`HTTP`, `WEBHOOK`, or `WEBSOCKET`)
`broadcast`	`bool`	`False`	Broadcast responses to all connected WebSocket clients (only valid with `WEBSOCKET` protocol)

Note: APIProtocol and restspec are builtins and do not require an import statement. HTTPMethod must be imported with import from http { HTTPMethod }.

Custom HTTP Method#

By default, walkers are exposed as POST endpoints. Use @restspec to change this:

import from http { HTTPMethod }

@restspec(method=HTTPMethod.GET)
walker :pub get_users {
    can fetch with Root entry {
        report [];
    }
}

This walker is now accessible at GET /walker/get_users instead of POST.

Custom Path#

Override the auto-generated path:

@restspec(method=HTTPMethod.GET, path="/custom/users")
walker :pub list_users {
    can fetch with Root entry {
        report [];
    }
}

Accessible at GET /custom/users.

Functions#

@restspec also works on standalone functions:

@restspec(method=HTTPMethod.GET)
def :pub health_check() -> dict {
    return {"status": "healthy"};
}

@restspec(method=HTTPMethod.GET, path="/custom/status")
def :pub app_status() -> dict {
    return {"status": "running", "version": "1.0.0"};
}

Webhook Mode#

See the Webhooks section below.

Authentication#

User Registration#

curl -X POST http://localhost:8000/user/register \
  -H "Content-Type: application/json" \
  -d '{"email": "user@example.com", "password": "secret"}'

curl -X POST http://localhost:8000/user/login \
  -H "Content-Type: application/json" \
  -d '{"email": "user@example.com", "password": "secret"}'

Returns:

{
  "access_token": "eyJ...",
  "token_type": "bearer"
}

Authenticated Requests#

curl -X POST http://localhost:8000/walker/my_walker \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{}'

JWT Configuration#

Configure JWT authentication via environment variables:

Variable	Description	Default
`JWT_SECRET`	Secret key for JWT signing	`supersecretkey`
`JWT_ALGORITHM`	JWT algorithm	`HS256`
`JWT_EXP_DELTA_DAYS`	Token expiration in days	`7`

SSO (Single Sign-On)#

jac-scale supports SSO with external identity providers. Currently supported: Google.

Configuration:

Variable	Description
`SSO_HOST`	SSO callback host URL (default: `http://localhost:8000/sso`)
`SSO_GOOGLE_CLIENT_ID`	Google OAuth client ID
`SSO_GOOGLE_CLIENT_SECRET`	Google OAuth client secret

SSO Endpoints:

Method	Path	Description
GET	`/sso/{platform}/login`	Redirect to provider login page
GET	`/sso/{platform}/register`	Redirect to provider registration
GET	`/sso/{platform}/login/callback`	OAuth callback handler

Example:

# Redirect user to Google login
curl http://localhost:8000/sso/google/login

Permissions & Access Control#

Access Levels#

Level	Value	Description
`NO_ACCESS`	`-1`	No access to the object
`READ`	`0`	Read-only access
`CONNECT`	`1`	Can traverse edges to/from this object
`WRITE`	`2`	Full read/write access

Granting Permissions#

To Everyone#

Use perm_grant to allow all users to access an object at a given level:

with entry {
    # Allow everyone to read this node
    perm_grant(node, READ);

    # Allow everyone to write
    perm_grant(node, WRITE);
}

To a Specific Root#

Use allow_root to grant access to a specific user's root graph:

with entry {
    # Allow a specific user to read this node
    allow_root(node, target_root_id, READ);

    # Allow write access
    allow_root(node, target_root_id, WRITE);
}

Revoking Permissions#

From Everyone#

with entry {
    # Revoke all public access
    perm_revoke(node);
}

From a Specific Root#

with entry {
    # Revoke a specific user's access
    disallow_root(node, target_root_id, READ);
}

Walker Access Levels#

Walkers have three access levels when served as API endpoints:

Access	Description
Public (`:pub`)	Accessible without authentication
Protected (default)	Requires JWT authentication
Private (`:priv`)	Only accessible by directly defined walkers (not imported)

Permission Functions Reference#

Function	Signature	Description
`perm_grant`	`perm_grant(archetype, level)`	Allow everyone to access at given level
`perm_revoke`	`perm_revoke(archetype)`	Remove all public access
`allow_root`	`allow_root(archetype, root_id, level)`	Grant access to a specific root
`disallow_root`	`disallow_root(archetype, root_id, level)`	Revoke access from a specific root

Webhooks#

Webhooks allow external services (payment processors, CI/CD systems, messaging platforms, etc.) to send real-time notifications to your Jac application. Jac-Scale provides:

Dedicated /webhook/ endpoints for webhook walkers
API key authentication for secure access
HMAC-SHA256 signature verification to validate request integrity
Automatic endpoint generation based on walker configuration

Configuration#

Webhook configuration is managed via the jac.toml file in your project root.

[plugins.scale.webhook]
secret = "your-webhook-secret-key"
signature_header = "X-Webhook-Signature"
verify_signature = true
api_key_expiry_days = 365

Option	Type	Default	Description
`secret`	string	`"webhook-secret-key"`	Secret key for HMAC signature verification. Can also be set via `WEBHOOK_SECRET` environment variable.
`signature_header`	string	`"X-Webhook-Signature"`	HTTP header name containing the HMAC signature.
`verify_signature`	boolean	`true`	Whether to verify HMAC signatures on incoming requests.
`api_key_expiry_days`	integer	`365`	Default expiry period for API keys in days. Set to `0` for permanent keys.

Environment Variables:

For production deployments, use environment variables for sensitive values:

export WEBHOOK_SECRET="your-secure-random-secret"

Creating Webhook Walkers#

To create a webhook endpoint, use the @restspec(protocol=APIProtocol.WEBHOOK) decorator on your walker definition.

Basic Webhook Walker#

@restspec(protocol=APIProtocol.WEBHOOK)
walker PaymentReceived {
    has payment_id: str,
        amount: float,
        currency: str = 'USD';

    can process with Root entry {
        # Process the payment notification
        report {
            "status": "success",
            "message": f"Payment {self.payment_id} received",
            "amount": self.amount,
            "currency": self.currency
        };
    }
}

This walker will be accessible at POST /webhook/PaymentReceived.

Important Notes#

Webhook walkers are only accessible via /webhook/{walker_name} endpoints
They are not accessible via the standard /walker/{walker_name} endpoint

API Key Management#

Webhook endpoints require API key authentication. Users must first create an API key before calling webhook endpoints.

Creating an API Key#

Endpoint: POST /api-key/create

Headers:

Authorization: Bearer <jwt_token> (required)

Request Body:

{
    "name": "My Webhook Key",
    "expiry_days": 30
}

Response:

{
    "api_key": "eyJhbGciOiJIUzI1NiIs...",
    "api_key_id": "a1b2c3d4e5f6...",
    "name": "My Webhook Key",
    "created_at": "2024-01-15T10:30:00Z",
    "expires_at": "2024-02-14T10:30:00Z"
}

Listing API Keys#

Endpoint: GET /api-key/list

Headers:

Authorization: Bearer <jwt_token> (required)

Calling Webhook Endpoints#

Webhook endpoints require two headers for authentication:

X-API-Key: The API key obtained from /api-key/create
X-Webhook-Signature: HMAC-SHA256 signature of the request body

Generating the Signature#

The signature is computed as: HMAC-SHA256(request_body, api_key)

cURL Example:

API_KEY="eyJhbGciOiJIUzI1NiIs..."
PAYLOAD='{"payment_id":"PAY-12345","amount":99.99,"currency":"USD"}'
SIGNATURE=$(echo -n "$PAYLOAD" | openssl dgst -sha256 -hmac "$API_KEY" | cut -d' ' -f2)

curl -X POST "http://localhost:8000/webhook/PaymentReceived" \
    -H "Content-Type: application/json" \
    -H "X-API-Key: $API_KEY" \
    -H "X-Webhook-Signature: $SIGNATURE" \
    -d "$PAYLOAD"

Webhook vs Regular Walkers#

Feature	Regular Walker (`/walker/`)	Webhook Walker (`/webhook/`)
Authentication	JWT Bearer token	API Key + HMAC Signature
Use Case	User-facing APIs	External service callbacks
Access Control	User-scoped	Service-scoped
Signature Verification	No	Yes (HMAC-SHA256)
Endpoint Path	`/walker/{name}`	`/webhook/{name}`

Webhook API Reference#

Webhook Endpoints#

Method	Path	Description
POST	`/webhook/{walker_name}`	Execute webhook walker

API Key Endpoints#

Method	Path	Description
POST	`/api-key/create`	Create a new API key
GET	`/api-key/list`	List all API keys for user
DELETE	`/api-key/{api_key_id}`	Revoke an API key

Required Headers for Webhook Requests#

Header	Required	Description
`Content-Type`	Yes	Must be `application/json`
`X-API-Key`	Yes	API key from `/api-key/create`
`X-Webhook-Signature`	Yes*	HMAC-SHA256 signature (*if `verify_signature` is enabled)

WebSockets#

Jac Scale provides built-in support for WebSocket endpoints, enabling real-time bidirectional communication between clients and walkers.

Overview#

WebSockets allow persistent, full-duplex connections between a client and your Jac application. Unlike REST endpoints (single request-response), a WebSocket connection stays open, allowing multiple messages to be exchanged in both directions. Jac Scale provides:

Dedicated /ws/ endpoints for WebSocket walkers
Persistent connections with a message loop
JSON message protocol for sending walker fields and receiving results
JWT authentication via query parameter or message payload
Connection management with automatic cleanup on disconnect
HMR support in dev mode for live reloading

Creating WebSocket Walkers#

To create a WebSocket endpoint, use the @restspec(protocol=APIProtocol.WEBSOCKET) decorator on an async walker definition.

Basic WebSocket Walker (Public)#

@restspec(protocol=APIProtocol.WEBSOCKET)
async walker : pub EchoMessage {
    has message: str;
    has client_id: str = "anonymous";

    async can echo with Root entry {
        report {
            "echo": self.message,
            "client_id": self.client_id
        };
    }
}

This walker will be accessible at ws://localhost:8000/ws/EchoMessage.

Authenticated WebSocket Walker#

To create a private walker that requires JWT authentication, simply remove : pub from the walker definition.

Broadcasting WebSocket Walker#

Use broadcast=True to send messages to ALL connected clients of this walker:

@restspec(protocol=APIProtocol.WEBSOCKET, broadcast=True)
async walker : pub ChatRoom {
    has message: str;
    has sender: str = "anonymous";

    async can handle with Root entry {
        report {
            "type": "message",
            "sender": self.sender,
            "content": self.message
        };
    }
}

When a client sends a message, all connected clients receive the response, making it ideal for:

Chat rooms
Live notifications
Real-time collaboration
Game state synchronization

Private Broadcasting Walker#

To create a private broadcasting walker, remove : pub from the walker definition. Only authenticated users can connect and send messages, and all authenticated users receive broadcasts.

Important Notes#

WebSocket walkers must be declared as async walker
Use : pub for public access (no authentication required) or omit it to require JWT auth
Use broadcast=True to send responses to ALL connected clients (only valid with WEBSOCKET protocol)
WebSocket walkers are only accessible via ws://host/ws/{walker_name}
The connection stays open until the client disconnects

Storage#

Jac provides a built-in storage abstraction for file and blob operations. The core runtime ships with a local filesystem implementation, and jac-scale can override it with cloud storage backends -- all through the same store() builtin.

The `store()` Builtin#

The recommended way to get a storage instance is the store() builtin. It requires no imports and is automatically hookable by plugins:

# Get a storage instance (no imports needed)
glob storage = store();

# With custom base path
glob storage = store(base_path="./uploads");

# With all options
glob storage = store(base_path="./uploads", create_dirs=True);

Parameter	Type	Default	Description
`base_path`	`str`	`"./storage"`	Root directory for all files
`create_dirs`	`bool`	`True`	Create base directory if it doesn't exist

Without jac-scale, store() returns a LocalStorage instance. With jac-scale installed, it returns a configuration-driven backend (reading from jac.toml and environment variables).

Storage Interface#

All storage instances provide these methods:

Method	Signature	Description
`upload`	`upload(source, destination, metadata=None) -> str`	Upload a file (from path or file object)
`download`	`download(source, destination=None) -> bytes\\|None`	Download a file (returns bytes if no destination)
`delete`	`delete(path) -> bool`	Delete a file or directory
`exists`	`exists(path) -> bool`	Check if a path exists
`list_files`	`list_files(prefix="", recursive=False)`	List files (yields paths)
`get_metadata`	`get_metadata(path) -> dict`	Get file metadata (size, modified, created, is_dir, name)
`copy`	`copy(source, destination) -> bool`	Copy a file within storage
`move`	`move(source, destination) -> bool`	Move a file within storage

Usage Example#

import from http { UploadFile }
import from uuid { uuid4 }

glob storage = store(base_path="./uploads");

walker :pub upload_file {
    has file: UploadFile;
    has folder: str = "documents";

    can process with Root entry {
        unique_name = f"{uuid4()}.dat";
        path = f"{self.folder}/{unique_name}";

        # Upload file
        storage.upload(self.file.file, path);

        # Get metadata
        metadata = storage.get_metadata(path);

        report {
            "success": True,
            "storage_path": path,
            "size": metadata["size"]
        };
    }
}

walker :pub list_files {
    has folder: str = "documents";
    has recursive: bool = False;

    can process with Root entry {
        files = [];
        for path in storage.list_files(self.folder, self.recursive) {
            metadata = storage.get_metadata(path);
            files.append({
                "path": path,
                "size": metadata["size"],
                "name": metadata["name"]
            });
        }
        report {"files": files};
    }
}

walker :pub download_file {
    has path: str;

    can process with Root entry {
        if not storage.exists(self.path) {
            report {"error": "File not found"};
            return;
        }
        content = storage.download(self.path);
        report {"content": content, "size": len(content)};
    }
}

Configuration#

Configure storage in jac.toml:

[storage]
storage_type = "local"       # Storage backend type
base_path = "./storage"      # Base directory for files
create_dirs = true           # Auto-create directories

Option	Type	Default	Description
`storage_type`	string	`"local"`	Storage backend (`local`)
`base_path`	string	`"./storage"`	Base path for file storage
`create_dirs`	boolean	`true`	Automatically create directories

Environment Variables:

Variable	Description
`JAC_STORAGE_TYPE`	Storage type (overrides jac.toml)
`JAC_STORAGE_PATH`	Base directory (overrides jac.toml)
`JAC_STORAGE_CREATE_DIRS`	Auto-create directories (`"true"`/`"false"`)

Configuration priority: jac.toml > environment variables > defaults.

StorageFactory (Advanced)#

For advanced use cases, you can use StorageFactory directly instead of the store() builtin:

import from jac_scale.factories.storage_factory { StorageFactory }

# Create with explicit type and config
glob config = {"base_path": "./my-files", "create_dirs": True};
glob storage = StorageFactory.create("local", config);

# Create using jac.toml / env var / defaults
glob default_storage = StorageFactory.get_default();

Graph Traversal API#

Traverse Endpoint#

POST /traverse

Parameters#

Parameter	Type	Description	Default
`source`	str	Starting node/edge ID	root
`depth`	int	Traversal depth	1
`detailed`	bool	Include archetype context	false
`node_types`	list	Filter by node types	all
`edge_types`	list	Filter by edge types	all

Example#

curl -X POST http://localhost:8000/traverse \
  -H "Authorization: Bearer <token>" \
  -H "Content-Type: application/json" \
  -d '{
    "depth": 3,
    "node_types": ["User", "Post"],
    "detailed": true
  }'

Async Walkers#

walker async_processor {
    has items: list;

    async can process with Root entry {
        results = [];
        for item in self.items {
            result = await process_item(item);
            results.append(result);
        }
        report results;
    }
}

Direct Database Access (kvstore)#

Direct database operations without graph layer abstraction. Supports MongoDB (document queries) and Redis (key-value with TTL/atomic ops).

import from jac_scale.lib { kvstore }

with entry {
    mongo_db = kvstore(db_name='my_app', db_type='mongodb');
    redis_db = kvstore(db_name='cache', db_type='redis');
}

Parameters: db_name (str), db_type ('mongodb'|'redis'), uri (str|None - priority: explicit → MONGODB_URI/REDIS_URL env vars → jac.toml)

MongoDB Operations#

Common Methods: get(), set(), delete(), exists() Query Methods: find_one(), find(), insert_one(), insert_many(), update_one(), update_many(), delete_one(), delete_many(), find_by_id(), update_by_id(), delete_by_id()

Example:

import from jac_scale.lib { kvstore }

with entry {
    db = kvstore(db_name='my_app', db_type='mongodb');

    db.insert_one('users', {'name': 'Alice', 'role': 'admin', 'age': 30});
    alice = db.find_one('users', {'name': 'Alice'});
    admins = list(db.find('users', {'role': 'admin'}));
    older = list(db.find('users', {'age': {'$gt': 28}}));

    db.update_one('users', {'name': 'Alice'}, {'$set': {'age': 31}});
    db.delete_one('users', {'name': 'Bob'});

    db.set('user:123', {'status': 'active'}, 'sessions');
}

Query Operators: $eq, $gt, $gte, $lt, $lte, $in, $ne, $and, $or

Redis Operations#

Common Methods: get(), set(), delete(), exists() Redis Methods: set_with_ttl(), expire(), incr(), scan_keys()

Example:

import from jac_scale.lib { kvstore }

with entry {
    cache = kvstore(db_name='cache', db_type='redis');

    cache.set('session:user123', {'user_id': '123', 'username': 'alice'});
    cache.set_with_ttl('temp:token', {'token': 'xyz'}, ttl=60);
    cache.set_with_ttl('cache:profile', {'name': 'Alice'}, ttl=3600);

    cache.incr('stats:views');
    sessions = cache.scan_keys('session:*');
    cache.expire('session:user123', 1800);
}

Note: Database-specific methods raise NotImplementedError on wrong database type.

Database Configuration#

Environment Variables#

Variable	Description	Default
`MONGODB_URI`	MongoDB connection URI	None
`REDIS_URL`	Redis connection URL	None
`K8s_MONGODB`	Enable MongoDB deployment	`false`
`K8s_REDIS`	Enable Redis deployment	`false`

Memory Hierarchy#

jac-scale uses a tiered memory system:

Tier	Backend	Purpose
L1	In-memory	Volatile runtime state
L2	Redis	Cache layer
L3	MongoDB	Persistent storage

Kubernetes Deployment#

Deploy#

# Deploy to Kubernetes
jac start app.jac --scale

# Build Docker image and deploy
jac start app.jac --scale --build

Remove Deployment#

jac destroy app.jac

Environment Variables#

Variable	Description	Default
`APP_NAME`	Application name for K8s resources	`jaseci`
`K8s_NAMESPACE`	Kubernetes namespace	`default`
`K8s_NODE_PORT`	External NodePort	`30001`
`K8s_CPU_REQUEST`	CPU resource request	None
`K8s_CPU_LIMIT`	CPU resource limit	None
`K8s_MEMORY_REQUEST`	Memory resource request	None
`K8s_MEMORY_LIMIT`	Memory resource limit	None
`K8s_READINESS_INITIAL_DELAY`	Readiness probe initial delay (seconds)	`10`
`K8s_READINESS_PERIOD`	Readiness probe period (seconds)	`20`
`K8s_LIVENESS_INITIAL_DELAY`	Liveness probe initial delay (seconds)	`10`
`K8s_LIVENESS_PERIOD`	Liveness probe period (seconds)	`20`
`K8s_LIVENESS_FAILURE_THRESHOLD`	Failure threshold before restart	`80`
`DOCKER_USERNAME`	DockerHub username	None
`DOCKER_PASSWORD`	DockerHub password/token	None

Package Version Pinning#

Configure specific package versions for Kubernetes deployments:

[plugins.scale.kubernetes.plugin_versions]
jaclang = "0.1.5"      # Specific version
jac_scale = "latest"   # Latest from PyPI (default)
jac_client = "0.1.0"   # Specific version
jac_byllm = "none"     # Skip installation

Package	Description	Default
`jaclang`	Core Jac language package	latest
`jac_scale`	Scaling plugin	latest
`jac_client`	Client/frontend support	latest
`jac_byllm`	LLM integration (use "none" to skip)	latest

Health Checks#

Health Endpoint#

Create a health walker:

walker health {
    can check with Root entry {
        report {"status": "healthy"};
    }
}

Access at: POST /walker/health

Readiness Check#

walker ready {
    can check with Root entry {
        db_ok = check_database();
        cache_ok = check_cache();

        if db_ok and cache_ok {
            report {"status": "ready"};
        } else {
            report {
                "status": "not_ready",
                "db": db_ok,
                "cache": cache_ok
            };
        }
    }
}

Builtins#

Root Access#

with entry {
    # Get all roots in memory/database
    roots = allroots();
}

Memory Commit#

with entry {
    # Commit memory to database
    commit();
}

CLI Commands#

Command	Description
`jac start app.jac`	Start local API server
`jac start app.jac --scale`	Deploy to Kubernetes
`jac start app.jac --scale --build`	Build image and deploy
`jac destroy app.jac`	Remove Kubernetes deployment

API Documentation#

When server is running:

Swagger UI: http://localhost:8000/docs
ReDoc: http://localhost:8000/redoc
OpenAPI JSON: http://localhost:8000/openapi.json

Prometheus Metrics#

jac-scale provides built-in Prometheus metrics collection for monitoring HTTP requests and walker execution. When enabled, a /metrics endpoint is automatically registered for Prometheus to scrape.

Configuration#

Configure metrics in jac.toml:

[plugins.scale.metrics]
enabled = true                  # Enable metrics collection and /metrics endpoint
endpoint = "/metrics"           # Prometheus scrape endpoint path
namespace = "myapp"             # Metrics namespace prefix
walker_metrics = true           # Enable per-walker execution timing
histogram_buckets = [0.005, 0.01, 0.025, 0.05, 0.075, 0.1, 0.25, 0.5, 0.75, 1.0, 2.5, 5.0, 10.0]

Option	Type	Default	Description
`enabled`	bool	`false`	Enable Prometheus metrics collection and `/metrics` endpoint
`endpoint`	string	`"/metrics"`	Path for the Prometheus scrape endpoint
`namespace`	string	`"jac_scale"`	Metrics namespace prefix
`walker_metrics`	bool	`false`	Enable walker execution timing metrics
`histogram_buckets`	list	`[0.005, ..., 10.0]`	Histogram bucket boundaries in seconds

Note: If namespace is not set, it is derived from the Kubernetes namespace config (sanitized) or defaults to "jac_scale".

Exposed Metrics#

Metric	Type	Labels	Description
`{namespace}_http_requests_total`	Counter	`method`, `path`, `status_code`	Total HTTP requests processed
`{namespace}_http_request_duration_seconds`	Histogram	`method`, `path`	HTTP request latency in seconds
`{namespace}_http_requests_in_progress`	Gauge	--	Concurrent HTTP requests
`{namespace}_walker_duration_seconds`	Histogram	`walker_name`, `success`	Walker execution duration (only when `walker_metrics=true`)

Usage#

# Scrape metrics
curl http://localhost:8000/metrics

The metrics endpoint is auto-registered as a GET route with OpenAPI tag "Monitoring". Requests to the metrics endpoint itself are excluded from tracking.

Kubernetes Secrets#

Manage sensitive environment variables securely in Kubernetes deployments using the [plugins.scale.secrets] section.

Configuration#

[plugins.scale.secrets]
OPENAI_API_KEY = "${OPENAI_API_KEY}"
DATABASE_PASSWORD = "${DB_PASS}"
STATIC_VALUE = "hardcoded-value"

Values using ${ENV_VAR} syntax are resolved from the local environment at deploy time. The resolved key-value pairs are created as a proper Kubernetes Secret ({app_name}-secrets) and injected into pods via envFrom.secretRef.

How It Works#

At jac start --scale, environment variable references (${...}) are resolved
A Kubernetes Opaque Secret named {app_name}-secrets is created (or updated if it already exists)
The Secret is attached to the deployment pod spec via envFrom.secretRef
All keys become environment variables inside the container
On jac destroy, the Secret is automatically cleaned up

Example#

# jac.toml
[plugins.scale.secrets]
OPENAI_API_KEY = "${OPENAI_API_KEY}"
MONGO_PASSWORD = "${MONGO_PASSWORD}"
JWT_SECRET = "${JWT_SECRET}"

# Set local env vars, then deploy
export OPENAI_API_KEY="sk-..."
export MONGO_PASSWORD="secret123"
export JWT_SECRET="my-jwt-key"

jac start app.jac --scale --build

This eliminates the need for manual kubectl create secret commands after deployment.

jac-scale Reference#

Installation#

Starting a Server#

Basic Server#

Server Options#

Examples#

API Endpoints#

Automatic Endpoint Generation#

Request Format#

Response Format#

@restspec Decorator#

Options#

Custom HTTP Method#

Custom Path#

Functions#

Webhook Mode#

Authentication#

User Registration#

User Login#

Authenticated Requests#

JWT Configuration#

SSO (Single Sign-On)#

Permissions & Access Control#

Access Levels#

Granting Permissions#

To Everyone#

To a Specific Root#

Revoking Permissions#

From Everyone#

From a Specific Root#

Walker Access Levels#

Permission Functions Reference#

Webhooks#

Configuration#

Creating Webhook Walkers#

Basic Webhook Walker#

Important Notes#

API Key Management#

Creating an API Key#

Listing API Keys#

Calling Webhook Endpoints#

Generating the Signature#

Webhook vs Regular Walkers#

Webhook API Reference#

Webhook Endpoints#

API Key Endpoints#

Required Headers for Webhook Requests#

WebSockets#

Overview#

Creating WebSocket Walkers#

Basic WebSocket Walker (Public)#

Authenticated WebSocket Walker#

Broadcasting WebSocket Walker#

Private Broadcasting Walker#

Important Notes#

Storage#

The store() Builtin#

Storage Interface#

Usage Example#

Configuration#

StorageFactory (Advanced)#

Graph Traversal API#

Traverse Endpoint#

Parameters#

Example#

Async Walkers#

Direct Database Access (kvstore)#

MongoDB Operations#

Redis Operations#

Database Configuration#

Environment Variables#

Memory Hierarchy#

Kubernetes Deployment#

Deploy#

Remove Deployment#

Environment Variables#

Package Version Pinning#

Health Checks#

Health Endpoint#

Readiness Check#

The `store()` Builtin#