# Update a changelog

Updates an existing changelog by its unique identifier.

You can update:
- title - The changelog title
- htmlContent - HTML content (one of htmlContent or markdownContent)
- markdownContent - Markdown content (one of htmlContent or markdownContent)
- categories - Array of category names
- featuredImage - Featured image URL
- allowedSegmentIds - Segment IDs for access control
- date - The date of the changelog

### Content Format

Provide content in one of two formats:
- htmlContent - HTML content of the changelog
- markdownContent - Markdown content of the changelog

Note: For images in content, you can use:
- External URLs in img src attributes (automatically uploaded to our storage)
- Base64 encoded data URIs (data:image/...) which are processed and stored

### Categories

Provide category names as an array. The categories must already exist in your organization.

Example: ["New", "Fixed", "Improved"]

### Response

Returns the updated changelog object with all fields populated.

### Errors

- 400 - Invalid changelog ID format or invalid input
- 404 - Changelog not found or doesn't belong to your organization

Endpoint: PATCH /v2/changelogs/{id}
Version: 2026-01-01.nova
Security: bearerAuth

## Header parameters:

  - `Featurebase-Version` (string)
    API version for this request. Defaults to your organization's configured API version if not specified.
    Example: "2026-01-01.nova"

## Path parameters:

  - `id` (string, required)
    Changelog unique identifier
    Example: "507f1f77bcf86cd799439011"

## Request fields (application/json):

  - `title` (string)
    The title of the changelog
    Example: "Updated Features Release"

  - `htmlContent` (string)
    The HTML content of the changelog. Provide either htmlContent or markdownContent. For images, external URLs and base64 data URIs are automatically processed and stored.
    Example: "<p>Updated features to explore.</p>"

  - `markdownContent` (string)
    The markdown content of the changelog. Provide either htmlContent or markdownContent. For images, external URLs and base64 data URIs are automatically processed and stored.
    Example: "Updated features to explore."

  - `categories` (array)
    An array of category names to which the changelog belongs
    Example: ["New","Fixed","Improved"]

  - `featuredImage` (string)
    The URL of the featured image for the changelog. External URLs will be uploaded to our storage.
    Example: "https://example.com/image.png"

  - `allowedSegmentIds` (array)
    An array of segment IDs that are allowed to view the changelog
    Example: ["507f1f77bcf86cd799439011"]

  - `date` (string,null)
    The date of the changelog
    Example: "2024-01-15"

## Response 200 fields (application/json):

  - `object` (string, required)
    Object type identifier
    Enum: "changelog"

  - `id` (string, required)
    Unique identifier
    Example: "6457e3ff70afca5d8c27dccc"

  - `title` (string, required)
    Changelog title
    Example: "Your awesome changelog!"

  - `slug` (string, required)
    URL-friendly slug
    Example: "your-awesome-changelog"

  - `url` (string, required)
    Public URL to view the changelog
    Example: "https://myorg.featurebase.app/en/changelog/your-awesome-changelog"

  - `content` (string, required)
    Content in HTML format
    Example: "<p>Your changelog content in HTML format.</p>"

  - `markdownContent` (string,null, required)
    Content in markdown format
    Example: "Your changelog content in markdown format."

  - `featuredImage` (string,null, required)
    Featured image URL
    Example: "https://cdn.example.com/images/feature.png"

  - `date` (string, required)
    Publication date as ISO 8601 timestamp
    Example: "2023-05-07T12:59:59.000Z"

  - `state` (string, required)
    State of the changelog
    Enum: "live", "draft"

  - `locale` (string, required)
    Locale of the changelog
    Enum: "bn", "bs", "pt-BR", "bg", "ca", "hr", "cs", "da", "nl", "en", "et", "fi", "fr", "de", "el", "hi", "hu", "id", "it", "ja", "ko", "lv", "lt", "ms", "mn", "nb", "pl", "pt", "ro", "ru", "sr", "zh-CN", "sk", "sl", "es", "sw", "sv", "th", "zh-TW", "tr", "uk", "vi"

  - `isPublished` (boolean, required)
    Whether the changelog is published (has a live version) in this locale
    Example: true

  - `isDraftDiffersFromLive` (boolean, required)
    Whether the draft content differs from the published live content

  - `publishedLocales` (array, required)
    Array of locale codes where the changelog is published
    Example: ["en","de"]

  - `availableLocales` (array, required)
    Array of locale codes where the changelog has content
    Example: ["en","de","fr"]

  - `slugs` (object, required)
    URL-friendly slugs for each locale
    Example: {"en":"your-awesome-changelog","de":"dein-tolles-changelog"}

  - `commentCount` (number, required)
    Number of comments
    Example: 2

  - `categories` (array, required)
    Categories the changelog belongs to

  - `categories.id` (string, required)
    Category unique identifier
    Example: "6438a1efda3640f8feb72121"

  - `categories.name` (string, required)
    Category name
    Example: "New Features"

  - `categories.roles` (array)
    Roles allowed to view this category
    Example: []

  - `organization` (string, required)
    Organization identifier
    Example: "myorg"

  - `notifications` (object, required)
    Notification settings for each locale

  - `allowedSegmentIds` (array, required)
    Segment IDs that are allowed to view this changelog
    Example: []

  - `emailSentToSubscribers` (boolean, required)
    Whether email notification was sent to subscribers
    Example: true

  - `createdAt` (string, required)
    ISO 8601 timestamp when created
    Example: "2023-12-12T00:00:00.000Z"

  - `updatedAt` (string, required)
    ISO 8601 timestamp when updated
    Example: "2023-12-13T00:00:00.000Z"

## Response 400 fields (application/json):

  - `error` (object, required)

  - `error.type` (string, required)
    The type of error returned
    Enum: "invalid_request_error"

  - `error.code` (string, required)
    Machine-readable error code
    Enum: "invalid_id"

  - `error.message` (string, required)
    Human-readable error message
    Example: "An error occurred"

  - `error.param` (string)
    The parameter that caused the error (if applicable)
    Example: "id"

  - `error.status` (number, required)
    HTTP status code
    Enum: 400

## Response 404 fields (application/json):

  - `error` (object, required)

  - `error.type` (string, required)
    The type of error returned
    Enum: "invalid_request_error"

  - `error.code` (string, required)
    Machine-readable error code
    Enum: "changelog_not_found"

  - `error.message` (string, required)
    Human-readable error message
    Example: "An error occurred"

  - `error.param` (string)
    The parameter that caused the error (if applicable)
    Example: "id"

  - `error.status` (number, required)
    HTTP status code
    Enum: 404