ZEzenzap
Topics (group chats/channels/conversations)

Set or update a topic cover image

Upload a cover image for an existing topic. Send the image as multipart/form-data with a filePart (the image).

Authorization: Your API key bot must be a member of the topic (returns 404 if not).

Cover image requirements:

  • must be a valid image (JPEG or PNG); undecodable images return 400
  • non-square images are automatically center-cropped to a square
  • max dimension 4096×4096; larger images return 400
  • max size 8 MB; converted to JPEG automatically

Behavior: The image is uploaded first; the topic's cover is only updated once the upload succeeds, so a topic never references a missing image.

patch/v2/topics/{topicId}/cover-image

Request

Path parameters

topicIdstring uuid required

The ID of the topic to set the cover image for

Headers

X-Signaturestring
Example:a3d5f8e7c2b1d4f6a8e9c7b5d3f1a2e4b6c8d0f2e4a6b8c0d2e4f6a8b0c2d4e6

HMAC signature of the request for authentication and replay protection.

Required only when authenticating with a static API key. If you are using an OAuth access token (issued by POST /oauth/token), omit this header — the JWT carries all the authentication and integrity guarantees.

Replay Protection: The signature includes a timestamp to prevent replay attacks. Requests with timestamps older than 5 minutes are rejected.

The signature payload differs by HTTP method:

  • POST/PUT/PATCH/DELETE: HMAC-SHA256 of {timestamp}.{body}
  • GET: HMAC-SHA256 of {timestamp}.{uri}

The signature is calculated as:

  1. Get the current Unix timestamp in milliseconds
  2. Determine the payload:
    • For POST/PUT/PATCH/DELETE: Use {timestamp}.{body} where body is the request body
    • For GET: Use {timestamp}.{uri} where uri is the full request URI (e.g., /v2/members?limit=10)
  3. Calculate HMAC-SHA256 of the combined payload using your API secret
  4. Hex-encode the output
  5. Include the timestamp in the X-Timestamp header

Example for GET request to /v2/members?limit=10:

timestamp = 1699564800000
payload = "1699564800000./v2/members?limit=10"
signature = HMAC-SHA256(secret, payload)
X-Signature: hex(signature)
X-Timestamp: 1699564800000

Example for POST request with body {"topicId":"123","text":"Hello"}:

timestamp = 1699564800000
payload = '1699564800000.{"topicId":"123","text":"Hello"}'
signature = HMAC-SHA256(secret, payload)
X-Signature: hex(signature)
X-Timestamp: 1699564800000

For multipart/form-data requests, sign the exact raw request body bytes (including boundaries and file bytes) as transmitted.

X-Timestampinteger
Example:1699564800000

Unix timestamp in milliseconds when the request was created. Used for replay protection — requests older than 5 minutes are rejected.

Required only when authenticating with a static API key. Omit when using an OAuth access token.

Request body multipart/form-data

filePartstring binary required

Cover image file. Must be a valid image (JPEG or PNG), max 4096×4096 and 8 MB. Automatically converted to JPEG and center-cropped to a square. Oversized or invalid images return 400.

Response

Cover image updated successfully

idstring uuid

The topic ID

updatedAtinteger

Unix timestamp in milliseconds when the topic was updated

Example response

{
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "updatedAt": 1699564800000
}

Changes

No recorded changes to this operation across all 1 revision of this API.