Subscribe to a channel

POST https://chat.zulip.org/api/v1/users/me/subscriptions

Subscribe one or more users to one or more channels.

If any of the specified channels do not exist, they are automatically created. The initial channel settings will be determined by the optional parameters, like invite_only, detailed below.

Note that the ability to subscribe oneself and/or other users to a specified channel depends on the channel's privacy settings.

Changes: Before Zulip 8.0 (feature level 208), if a user specified by the principals parameter was a deactivated user, or did not exist, then an HTTP status code of 403 was returned with code: "UNAUTHORIZED_PRINCIPAL" in the error response. As of this feature level, an HTTP status code of 400 is returned with code: "BAD_REQUEST" in the error response for these cases.

Usage examples

#!/usr/bin/env python3

import zulip

# Pass the path to your zuliprc file here.
client = zulip.Client(config_file="~/zuliprc")

# Create and subscribe to channel "python-test".
result = client.add_subscriptions(
    streams=[
        {
            "name": "python-test",
            "description": "Channel for testing Python",
        },
    ],
)
# To subscribe other users to a channel, you may pass
# the `principals` argument, like so:
result = client.add_subscriptions(
    streams=[
        {"name": "python-test"},
    ],
    principals=[user_id],
)
print(result)

More examples and documentation can be found here.

const zulipInit = require("zulip-js");

// Pass the path to your zuliprc file here.
const config = { zuliprc: "zuliprc" };

(async () => {
    const client = await zulipInit(config);

    // Subscribe to the channels "Verona" and "Denmark"
    const meParams = {
        subscriptions: JSON.stringify([{name: "Verona"}, {name: "Denmark"}]),
    };
    console.log(await client.users.me.subscriptions.add(meParams));

    // To subscribe another user to a channel, you may pass in
    // the `principals` parameter, like so:
    const user_id = 7;
    const anotherUserParams = {
        subscriptions: JSON.stringify([{name: "Verona"}, {name: "Denmark"}]),
        principals: JSON.stringify([user_id]),
    };
    console.log(await client.users.me.subscriptions.add(anotherUserParams));
})();

curl -sSX POST https://chat.zulip.org/api/v1/users/me/subscriptions \
    -u BOT_EMAIL_ADDRESS:BOT_API_KEY \
    --data-urlencode 'subscriptions=[{"description": "Italian city", "name": "Verona"}]'

To subscribe another user to a channel, you may pass in the principals parameter, like so:

curl -sSX POST https://chat.zulip.org/api/v1/users/me/subscriptions \
    -u BOT_EMAIL_ADDRESS:BOT_API_KEY \
    --data-urlencode 'subscriptions=[{"description": "Italian city", "name": "Verona"}]' \
    --data-urlencode 'principals=["ZOE@zulip.com"]'

Parameters

subscriptions (object)[] required

Example: [{"name": "Verona", "description": "Italian city"}]

A list of dictionaries containing the key name and value specifying the name of the channel to subscribe. If the channel does not exist a new channel is created. The description of the channel created can be specified by setting the dictionary key description with an appropriate value.

subscriptions object details:

  • name: string required

    The name of the channel.

    Clients should use the max_stream_name_length returned by the POST /register endpoint to determine the maximum channel name length.

  • description: string optional

    The description to use for a new channel being created, in text/markdown format.

    Clients should use the max_stream_description_length returned by the POST /register endpoint to determine the maximum channel description length.


principals (string)[] | (integer)[] optional

Example: ["ZOE@zulip.com"]

A list of user IDs (preferred) or Zulip API email addresses of the users to be subscribed to or unsubscribed from the channels specified in the subscriptions parameter. If not provided, then the requesting user/bot is subscribed.

Changes: The integer format is new in Zulip 3.0 (feature level 9).


authorization_errors_fatal boolean optional

Example: false

A boolean specifying whether authorization errors (such as when the requesting user is not authorized to access a private channel) should be considered fatal or not. When true, an authorization error is reported as such. When set to false, the response will be a 200 and any channels where the request encountered an authorization error will be listed in the unauthorized key.

Defaults to true.


announce boolean optional

Example: true

If one of the channels specified did not exist previously and is thus created by this call, this determines whether notification bot will send an announcement about the new channel's creation.

Defaults to false.


invite_only boolean optional

Example: true

As described above, this endpoint will create a new channel if passed a channel name that doesn't already exist. This parameters and the ones that follow are used to request an initial configuration of a created channel; they are ignored for channels that already exist.

This parameter determines whether any newly created channels will be private channels.

Defaults to false.


is_web_public boolean optional

Example: true

This parameter determines whether any newly created channels will be web-public channels.

Note that creating web-public channels requires the WEB_PUBLIC_STREAMS_ENABLED server setting to be enabled on the Zulip server in question, the organization to have enabled the enable_spectator_access realm setting, and the current use to have permission under the organization's can_create_web_public_channel_group realm setting.

Changes: New in Zulip 5.0 (feature level 98).

Defaults to false.


is_default_stream boolean optional

Example: true

This parameter determines whether any newly created channels will be added as default channels for new users joining the organization.

Changes: New in Zulip 8.0 (feature level 200). Previously, default channel status could only be changed using the dedicated API endpoint.

Defaults to false.


history_public_to_subscribers boolean optional

Example: false

Whether the channel's message history should be available to newly subscribed members, or users can only access messages they actually received while subscribed to the channel.

Corresponds to the shared history option in documentation.


stream_post_policy integer optional

Example: 2

Policy for which users can post messages to the channel.

  • 1 = Any user can post.
  • 2 = Only administrators can post.
  • 3 = Only full members can post.
  • 4 = Only moderators can post.

Changes: New in Zulip 3.0 (feature level 1), replacing the previous is_announcement_only boolean.

Defaults to 1.


message_retention_days string | integer optional

Example: "20"

Number of days that messages sent to this channel will be stored before being automatically deleted by the message retention policy. Two special string format values are supported:

  • "realm_default": Return to the organization-level setting.
  • "unlimited": Retain messages forever.

Changes: Prior to Zulip 5.0 (feature level 91), retaining messages forever was encoded using "forever" instead of "unlimited".

New in Zulip 3.0 (feature level 17).


can_remove_subscribers_group integer optional

Example: 20

ID of the user group whose members are allowed to unsubscribe others from the channel. Note that a user who is a member of the specified user group must also have access to the channel in order to unsubscribe others.

This setting can currently only be set to user groups that are system groups, except for the system groups named "role:internet" and "role:owners".

Changes: Before Zulip 8.0 (feature level 197), the can_remove_subscribers_group setting was named can_remove_subscribers_group_id.

New in Zulip 7.0 (feature level 161).


Response

Return values

  • subscribed: object

    A dictionary where the key is the ID of the user and the value is a list of the names of the channels that user was subscribed to as a result of the request.

    Changes: Before Zulip 10.0 (feature level 289), the user keys were Zulip API email addresses, not user ID.

    • {id}: (string)[]

      List of the names of the channels that were subscribed to as a result of the query.

  • already_subscribed: object

    A dictionary where the key is the ID of the user and the value is a list of the names of the channels that where the user was not added as a subscriber in this request, because they were already a subscriber.

    Changes: Before Zulip 10.0 (feature level 289), the user keys were Zulip API email addresses, not user IDs.

    • {id}: (string)[]

      List of the names of the channels that the user is already subscribed to.

  • unauthorized: (string)[]

    A list of names of channels that the requesting user/bot was not authorized to subscribe to. Only present if "authorization_errors_fatal": false.

Example response(s)

Changes: As of Zulip 7.0 (feature level 167), if any parameters sent in the request are not supported by this endpoint, a successful JSON response will include an ignored_parameters_unsupported array.

A typical successful JSON response may look like:

{
    "already_subscribed": {
        "1": [
            "testing-help"
        ]
    },
    "msg": "",
    "result": "success",
    "subscribed": {
        "2": [
            "testing-help"
        ]
    }
}

An example JSON response for when the requesting user does not have access to a private channel and "authorization_errors_fatal": true:

{
    "code": "BAD_REQUEST",
    "msg": "Unable to access channel (private).",
    "result": "error"
}