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dialog.open method

Facts​

DescriptionOpen a dialog with a user
Method Access
POST https://slack.com/api/dialog.open
ScopesNo scopes required
Content types
application/x-www-form-urlencoded
application/json
Rate LimitsTier 4: 100+ per minute

Arguments​

Required arguments

tokenstringRequired

Authentication token bearing required scopes. Tokens should be passed as an HTTP Authorization header or alternatively, as a POST parameter.

Example: xxxx-xxxxxxxxx-xxxx
dialogstringRequired

The dialog definition. This must be a JSON-encoded string.

trigger_idstringRequired

Exchange a trigger to post to the user.

Example: 12345.98765.abcd2358fdea

Usage info​

Dialogs are outmoded and are being replaced with modals.

If you are still using dialogs, we recommend upgrading them to modals using Block Kit.

Open a dialog with a user by exchanging a trigger_id received from another interaction. See the legacy dialogs documentation to learn how to obtain triggers define form elements.

As with all of our Web API methods, dialog.open primarily takes URL-encoded parameters as arguments. Similar to chat.postMessage, chat.unfurl, and chat.update this method also includes a parameter that expects a JSON object encoded with application/x-www-form-urlencoded.

A simple form you might create could be modeled in JSON as:

{
  "callback_id": "ryde-46e2b0",
  "title": "Request a Ride",
  "submit_label": "Request",
  "state": "Limo",
  "elements": [
    {
      "type": "text",
      "label": "Pickup Location",
      "name": "loc_origin"
    },
    {
      "type": "text",
      "label": "Dropoff Location",
      "name": "loc_destination"
    }
  ]
}

To prepare that as a HTTP POST to dialog.open, you'd optionally minify and then URL encode that JSON to a single string, displayed below as the value for the dialog POST body parameter.

POST /api/dialog.open
token=xoxb-such-and-such
&trigger_id=13345224609.738474920.8088930838d88f008e0
&dialog=%7B%22callback_id%22%3A%22ryde-46e2b0%22%2C%22title%22%3A%22Request%20a%20Ride%22%2C%22submit_label%22%3A%22Request%22%2C%22state%22%3A%22Limo%22%2C%22elements%22%3A%5B%7B%22type%22%3A%22text%22%2C%22label%22%3A%22Pickup%20Location%22%2C%22name%22%3A%22loc_origin%22%7D%2C%7B%22type%22%3A%22text%22%2C%22label%22%3A%22Dropoff%20Location%22%2C%22name%22%3A%22loc_destination%22%7D%5D%7D

You can avoid this nonsense by posting JSON instead.

Response​

Typical success response is quite minimal.

{
  "ok": true
}

Typical error response, before getting to any possible validation errors.

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

The impossibility of all possible errors expressed in a single response:

{
  "ok": false,
  "error": "validation_errors",
  "response_metadata": {
    "messages": [
      "The field `title` is required",
      "The field `callback_id` is required",
      "The field `elements` is required",
      "The field `title` cannot be longer than 24 characters",
      "The field `submit_button` cannot be longer than 24 characters",
      "The field `submit_button` can only be one word",
      "The field `callback_id` cannot be longer than 255 characters",
      "The field `state` cannot be longer than 3000 characters",
      "The field `elements` must be a list",
      "The field `elements` has to include at least one element",
      "The field `elements` cannot include more than ten elements",
      "Element 0 must be an object",
      "Element 1 is missing required field `type`",
      "Element 2 has an invalid `type`",
      "Element 3 is missing required field `name`",
      "Element 4 is missing required field `label`",
      "Element 5 has a repeated name",
      "Element 6 field `name` cannot be longer than 300 characters",
      "Element 7 field `hint` cannot be longer than 150 characters",
      "Element 8 field `label` cannot be longer than 48 characters",
      "Element 9 has an invalid `subtype`",
      "Element 10 field `min_length` must be between 0 and 150 (inclusive)",
      "Element 11 field `max_length` must be between 1 and 150 (inclusive)",
      "Element 12 field `value` cannot be longer than 150 characters",
      "Element 13 field `placeholder` cannot be longer than 150 characters",
      "Element 14 field `min_length` must be between 0 and 500 (inclusive)",
      "Element 14 field `max_length` must be between 1 and 500 (inclusive)",
      "Element 15 field `value` cannot be longer than 500 characters",
      "Element 16 field `placeholder` cannot be longer than 150 characters",
      "Element 17 field `placeholder` cannot be longer than 150 characters",
      "Element 18 field `options` must be a list",
      "Element 19 field `options` must have at least one option",
      "Element 20 field `options` must have fewer than 100 options",
      "Element 21 `options` item is missing required field `label`",
      "Element 22 `options` item is missing required field `value`",
      "Element 23 `options` item `label` field cannot exceed 75 characters",
      "Element 24 `options` item `value` field cannot exceed 75 characters"
    ]
  }
}

Assuming your submitted dialog elements were properly formatted, valid, and the trigger_id was viable, you will receive a minimal success response. If your form was invalid, Slack will try to provide a detailed accounting of why and provide the validation_errors error. Look for the response_metadata node and the messages array contained within for human-readable validation errors.

When we encounter an error with a specific form element, we'll indicate which element by a zero-indexed integer: 0 indicates the first provided element, 1 the second, and so on.

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 parameter in the response.

Error
Description
access_denied

Access to a resource specified in the request is denied.

accesslimited

Access to this method is limited on the current network

account_inactive

Authentication token is for a deleted user or workspace when using a bot token.

app_missing_action_url

The app associated with the used token doesn't have a Action URL configured in its interactive components settings.

cannot_create_dialog

Something exceptional occurred and the dialog could not be created.

deprecated_endpoint

The endpoint has been deprecated.

ekm_access_denied

Administrators have suspended the ability to post a message.

enterprise_is_restricted

The method cannot be called from an Enterprise.

failed_sending_dialog

Something exceptional occurred and the dialog could not be sent.

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.

internal_error

The server could not complete your operation(s) without encountering an error, likely due to a transient issue on our end. It's possible some aspect of the operation succeeded before the error was raised.

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_arguments

The method was called with invalid arguments.

invalid_array_arg

The method was passed an array as an argument. Please only input valid strings.

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.

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/json application/x-www-form-urlencoded multipart/form-data text/plain.

invalid_trigger

The provided trigger_id is invalid or cannot be used by this token.

method_deprecated

The method has been deprecated.

missing_dialog

No dialog argument was presented.

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.

missing_scope

The token used is not granted the specific scope permissions required to complete this request.

missing_trigger

No trigger_id argument was presented.

no_permission

The workspace token used in this request does not have the permissions necessary to complete the request. Make sure your app is a member of the conversation it's attempting to post a message to.

not_allowed_token_type

The token type used in this request is not allowed.

not_authed

No authentication token provided.

org_login_required

The workspace is undergoing an enterprise migration and will not be available until migration is complete.

ratelimited

The request has been ratelimited. Refer to the Retry-After header for when to retry the request.

request_timeout

The method was called via a POST request, but the POST data was either missing or truncated.

service_unavailable

The service is temporarily unavailable

team_access_not_granted

The token used is not granted the specific workspace access required to complete this request.

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.

token_expired

Authentication token has expired

token_revoked

Authentication token is for a deleted user or workspace or the app has been removed when using a user token.

trigger_exchanged

The provided trigger_id has already been exchanged.

trigger_expired

The provided trigger_id was presented after the 3 second limit.

two_factor_setup_required

Two factor setup is required.

validation_errors

The provided dialog could not be validated.