channels.mark

Sets the read cursor in a channel.

Facts

Method URL: https://slack.com/api/channels.mark

Preferred HTTP method: POST

Accepted content types: application/x-www-form-urlencoded, application/json

Rate limiting: Tier 3

Works with:

Token type	Required scope(s)
bot	`bot`
user	`channels:write` `post`

This method moves the read cursor in a channel.

Arguments

Argument	Example	Required	Description
`token`	`xxxx-xxxxxxxxx-xxxx`	Required	Authentication token bearing required scopes.
`channel`	`C1234567890`	Required	Channel to set reading cursor in.
`ts`	`1234567890.123456`	Required	Timestamp of the most recently seen message.

This method supports application/json via HTTP POST. Present your token in your request's Authorization header. Learn more.

Response

Typical success response

{
    "ok": true
}

Typical error response

{
    "ok": false,
    "error": "invalid_auth"
}

After making this call, the mark is saved to the database and broadcast via the message server to all open connections for the calling user.

Clients should try to avoid making this call too often. When needing to mark a read position, a client should set a timer before making the call. In this way, any further updates needed during the timeout will not generate extra calls (just one per channel). This is useful for when reading scroll-back history, or following a busy live channel. A timeout of 5 seconds is a good starting point. Be sure to flush these calls on shutdown/logout.

Errors

This table lists the expected errors that this method could return. However, other errors can be returned in the case where the service is down or other unexpected factors affect processing. Callers should always check the value of the ok params in the response.

Error	Description
`channel_not_found`	Value passed for `channel` was invalid.
`invalid_timestamp`	Value passed for `timestamp` was invalid.
`not_in_channel`	Caller is not a member of the channel.
`not_authed`	No authentication token provided.
`invalid_auth`	Some aspect of authentication cannot be validated. Either the provided token is invalid or the request originates from an IP address disallowed from making the request.
`account_inactive`	Authentication token is for a deleted user or workspace.
`token_revoked`	Authentication token is for a deleted user or workspace or the app has been removed.
`no_permission`	The workspace token used in this request does not have the permissions necessary to complete the request.
`org_login_required`	The workspace is undergoing an enterprise migration and will not be available until migration is complete.
`invalid_arg_name`	The method was passed an argument whose name falls outside the bounds of accepted or expected values. This includes very long names and names with non-alphanumeric characters other than `_`. If you get this error, it is typically an indication that you have made a very malformed API call.
`invalid_array_arg`	The method was passed a PHP-style array argument (e.g. with a name like `foo[7]`). These are never valid with the Slack API.
`invalid_charset`	The method was called via a `POST` request, but the `charset` specified in the `Content-Type` header was invalid. Valid charset names are: `utf-8` `iso-8859-1`.
`invalid_form_data`	The method was called via a `POST` request with `Content-Type` `application/x-www-form-urlencoded` or `multipart/form-data`, but the form data was either missing or syntactically invalid.
`invalid_post_type`	The method was called via a `POST` request, but the specified `Content-Type` was invalid. Valid types are: `application/x-www-form-urlencoded` `multipart/form-data` `text/plain`.
`missing_post_type`	The method was called via a `POST` request and included a data payload, but the request did not include a `Content-Type` header.
`team_added_to_org`	The workspace associated with your request is currently undergoing migration to an Enterprise Organization. Web API and other platform operations will be intermittently unavailable until the transition is complete.
`request_timeout`	The method was called via a `POST` request, but the `POST` data was either missing or truncated.
`fatal_error`	The server could not complete your operation(s) without encountering a catastrophic error. It's possible some aspect of the operation succeeded before the error was raised.

Warnings

This table lists the expected warnings that this method will return. However, other warnings can be returned in the case where the service is experiencing unexpected trouble.

Warning	Description
`missing_charset`	The method was called via a `POST` request, and recommended practice for the specified `Content-Type` is to include a `charset` parameter. However, no `charset` was present. Specifically, non-form-data content types (e.g. `text/plain`) are the ones for which `charset` is recommended.
`superfluous_charset`	The method was called via a `POST` request, and the specified `Content-Type` is not defined to understand the `charset` parameter. However, `charset` was in fact present. Specifically, form-data content types (e.g. `multipart/form-data`) are the ones for which `charset` is superfluous.