PostHog Handbook Library / Docs and Wizard

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# Hogref Schema

Auto TL;DR

## At a Glance

This long page covers these main areas. The list is generated from the article headings, so it updates with every handbook rebuild.

1. Root Object
2. Info
3. Class
4. Function
5. Parameter
6. TypeReference
7. Type
8. Property

The hierarchy of the HogRef JSON schema is as follows:

    Root
    ├── info (metadata)
    ├── categories[] (string labels)
    ├── classes[]
    │   ├── functions[]
    │   │   ├── params[]
    │   │   ├── returnType
    │   │   ├── examples[]
    │   │   ├── throws[]
    │   │   └── overloads[]
    │   ├── properties[]
    │   ├── staticMethods[]
    │   └── events[]
    └── types[]
        ├── properties[]
        ├── enumValues[]
        └── generic[]

##### Root Object

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | ✓ | Unique identifier for the SDK (e.g., 'posthog-js', 'stripe-node') | | `schemaVersion` | string | | Version of this schema format being used | | `info` | Info | ✓ | Metadata about the SDK | | `classes` | Class[] | ✓ | Main classes/modules exposed by the SDK | | `types` | Type[] | | Type definitions, interfaces, and enums | | `categories` | string[] | | List of functional categories for organizing methods |

---

##### Info

Metadata about the SDK.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | ✓ | Package/library identifier | | `title` | string | ✓ | Human-readable name of the SDK | | `version` | string | ✓ | Current version of the SDK | | `description` | string | | Brief description of what the SDK does | | `slugPrefix` | string | | URL-friendly prefix for documentation links | | `specUrl` | string (uri) | | URL to the source specification or repository | | `docsUrl` | string (uri) | | URL to the official documentation | | `license` | string | | License type (e.g., 'MIT', 'Apache-2.0') | | `platforms` | string[] | | Supported platforms (e.g., 'browser', 'node', 'react-native') |

---

##### Class

Main classes/modules exposed by the SDK.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | ✓ | Unique identifier for the class | | `title` | string | ✓ | Display name of the class | | `description` | string | | Overview of what this class provides | | `functions` | Function[] | ✓ | Methods and functions available on this class | | `properties` | Property[] | | Instance properties of this class | | `staticMethods` | Function[] | | Static methods on this class | | `events` | Event[] | | Events emitted by this class |

---

##### Function

Methods and functions available on a class.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | ✓ | Unique identifier for the function | | `title` | string | ✓ | Function name as it appears in code | | `description` | string | | Brief description of what the function does | | `details` | string \| null | | Extended explanation, usage notes, or caveats | | `category` | string | | Functional category (e.g., 'Initialization', 'Capture') | | `releaseTag` | ReleaseTag | | Stability/visibility status of the function | | `showDocs` | boolean | | Whether to display in public documentation | | `params` | Parameter[] | | Function parameters | | `returnType` | TypeReference | | Return type of the function | | `examples` | Example[] | | Code examples showing usage | | `throws` | ThrowsClause[] | | Exceptions/errors that may be thrown | | `since` | string | | Version when this function was introduced | | `deprecated` | string \| boolean | | Deprecation notice or true if deprecated | | `seeAlso` | string[] | | Related functions or documentation links | | `path` | string | | Source file path for this function | | `async` | boolean | | Whether this is an async function | | `overloads` | FunctionOverload[] | | Alternative function signatures |

---

##### Parameter

Function parameters.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `name` | string | ✓ | Parameter name | | `type` | string | ✓ | Type annotation for the parameter | | `description` | string | | What this parameter is for | | `isOptional` | boolean | | Whether this parameter is optional | | `defaultValue` | string | | Default value if not provided | | `isRest` | boolean | | Whether this is a rest parameter (...args) |

---

##### TypeReference

Reference to a type, used for return types and property types.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | | Reference ID to a type definition | | `name` | string | ✓ | Display name of the type |

---

##### Type

Type definitions, interfaces, and enums.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | ✓ | Unique identifier for this type | | `name` | string | ✓ | Type name | | `description` | string | | What this type represents | | `kind` | TypeKind | | Kind of type definition | | `properties` | Property[] | | Properties for object types | | `enumValues` | EnumValue[] | | Values for enum types | | `example` | string | | Inline type definition or usage example | | `path` | string | | Source file path | | `extends` | string[] | | Types this type extends | | `generic` | GenericParameter[] | | Generic type parameters |

---

##### Property

Properties on types or classes.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `name` | string | ✓ | Property name | | `type` | string | ✓ | Type of the property | | `description` | string | | What this property represents | | `isOptional` | boolean | | Whether this property is optional | | `isReadonly` | boolean | | Whether this property is read-only | | `defaultValue` | string | | Default value | | `deprecated` | string \| boolean | | Deprecation notice |

---

##### Example

Code examples demonstrating usage.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `id` | string | | Unique identifier for the example | | `name` | string | | Title describing what the example demonstrates | | `code` | string | ✓ | The example code | | `language` | string | | Programming language (e.g., 'javascript', 'typescript') | | `description` | string | | Additional explanation of the example |

---

##### Event

Events emitted by a class.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `name` | string | ✓ | Event name | | `description` | string | | When this event is emitted | | `payload` | string | | Type of data passed to event listeners |

---

##### ThrowsClause

Exceptions/errors that may be thrown by a function.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `type` | string | | Type of error thrown | | `description` | string | | When this error is thrown |

---

##### EnumValue

Values for enum types.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `name` | string | ✓ | Enum member name | | `value` | string \| number | ✓ | Enum member value | | `description` | string | | What this enum value represents |

---

##### GenericParameter

Generic type parameters.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `name` | string | ✓ | Generic parameter name (e.g., 'T') | | `constraint` | string | | Type constraint (e.g., 'extends string') | | `default` | string | | Default type |

---

##### FunctionOverload

Alternative function signatures for overloaded functions.

| Field | Type | Required | Description | |-------|------|----------|-------------| | `params` | Parameter[] | | Parameters for this overload | | `returnType` | TypeReference | | Return type for this overload | | `description` | string | | Description specific to this overload |

---

##### Enumerations

`ReleaseTag` enum:

| Value | Description | |-------|-------------| | `public` | Stable, public API | | `beta` | Beta feature, may change | | `alpha` | Alpha feature, likely to change | | `internal` | Internal use only | | `deprecated` | Deprecated, avoid use |

`TypeKind` enum:

| Value | Description | |-------|-------------| | `interface` | Interface definition | | `type` | Type alias | | `enum` | Enumeration | | `class` | Class definition |

##### Example JSON

    {
      "id": "example-sdk",
      "schemaVersion": "1.0",
      "info": {
        "id": "example-sdk",
        "title": "Example JavaScript SDK",
        "version": "1.0.0",
        "description": "Example SDK for tracking events.",
        "slugPrefix": "example-sdk",
        "specUrl": "https://github.com/example/example-sdk"
      },
      "categories": ["Capture"],
      "classes": [
        {
          "id": "ExampleClient",
          "title": "ExampleClient",
          "description": "The main client for tracking events.",
          "functions": [
            {
              "id": "capture",
              "title": "capture",
              "description": "Captures an event with optional properties.",
              "details": "You can capture arbitrary object-like values as events.",
              "category": "Capture",
              "releaseTag": "public",
              "showDocs": true,
              "params": [
                {
                  "name": "event_name",
                  "type": "string",
                  "description": "The name of the event (e.g., 'Sign Up', 'Button Click')",
                  "isOptional": false
                },
                {
                  "name": "properties",
                  "type": "Properties | null",
                  "description": "Properties to include with the event",
                  "isOptional": true
                }
              ],
              "returnType": {
                "id": "CaptureResult | undefined",
                "name": "CaptureResult | undefined"
              },
              "examples": [
                {
                  "id": "basic_event_capture",
                  "name": "basic event capture",
                  "code": "\n\n// basic event capture\nclient.capture('button-clicked', {\n    button_name: 'Get Started',\n    page: 'homepage'\n})\n\n"
                }
              ],
              "path": "lib/src/client.d.ts"
            }
          ]
        }
      ],
      "types": [
        {
          "id": "Properties",
          "name": "Properties",
          "properties": [],
          "path": "lib/src/types.d.ts",
          "example": "{\n    $timestamp: '2024-05-29T17:32:07.202Z',\n    $os: 'Mac OS X',\n    $browser: 'Chrome'\n}"
        }
      ]
    }

Canonical URL: https://posthog.com/handbook/docs-and-wizard/_snippets/hogref-schema

GitHub source: contents/handbook/docs-and-wizard/_snippets/hogref-schema.mdx

Content hash: `d60bc944b99f8921`