zulip/templates/zerver/help/stream-permissions.md

# Stream privacy settings

Streams are similar to chatrooms, IRC channels, or email lists in that they
determine who receives a message. There are three types of streams in Zulip.

* **Public**: Anyone other than guests can join, and anyone (other
  than guests) can view the complete message history without joining.

* **Private, shared history**: You must be added by a member of the stream. The
  complete message history is available as soon as you are added.

* **Private, protected history**: You must be added by a member of the
  stream. You only have access to the messages that are sent after you are added.

## Privacy model for private streams

At a high level:

* Organization admins can see and modify most aspects of a private stream,
  including the membership and estimated traffic. Admins generally cannot see stream
  messages or do things that would indirectly give them access to stream
  messages, like adding members or changing the stream privacy settings.

* Non-admin members cannot easily see which private streams exist, or interact with
  them in any way until they are added. Given a stream name, they can figure
  out whether a stream with that name exists, but cannot see any other
  details about the stream.

* From the perspective of a guest, all streams are private streams, and they
  additionally can't add other members to the streams they are subscribed to.

There are two situations in which an organization administrator can access
private stream messages:

* Via some types of [data export](/help/export-your-organization).

* Administrators can change the ownership of a bot. If a bot is subscribed
  to a private stream, then an administrator can get access to that stream by
  taking control of the bot, though the access will be limited to what the
  bot can do. (E.g. incoming webhook bots cannot read messages.)

## Detailed permissions

### Public streams

|                       | Org admins | Members   | Guests
|---                    |---         |---        |---
| Join                  | &#10004;   | &#10004;  |
| Unsubscribe           | &#9726;    | &#9726;   | &#9726;
| Add others            | &#10004;   | &#10004;  |
| See subscriber list   | &#10004;   | &#10004;  | &#9726;
| See full history      | &#10004;   | &#10004;  | &#9726;
| See estimated traffic | &#10004;   | &#10004;  | &#9726;
| Post                  | &#10004;   | &#10038;  | &#10038;
| Change the privacy    | &#10004;   |           |
| Rename                | &#10004;   |           |
| Edit the description  | &#10004;   |           |
| Remove others         | &#10004;   |           |
| Delete                | &#10004;   |           |

&#10004; Always

&#9726; &nbsp; If subscribed to the stream

&#10038; [Configurable](/help/stream-sending-policy).  Org admins and
Members can, by default, post to any public stream, and Guests can
only post to public streams if they are subscribed.

### Private streams


|                       | Org admins | Members   | Guests
|---                    |---         |---        |---
| Join                  |            |           |
| Unsubscribe           | &#9726;    | &#9726;   | &#9726;
| Add others            | &#9726;    | &#9726;   |
| See subscriber list   | &#10004;   | &#9726;   | &#9726;
| See full history      | &#10038;   | &#10038;  | &#10038;
| See estimated traffic | &#10004;   | &#9726;   | &#9726;
| Post                  | &#9726;    | &#10038;  | &#10038;
| Change the privacy    | &#9726;    |           |
| Rename                | &#10004;   |           |
| Edit the description  | &#10004;   |           |
| Remove others         | &#10004;   |           |
| Delete                | &#10004;   |           |

&#10004; Always

&#9726; &nbsp; If subscribed to the stream

&#10038; [Configurable](/help/stream-sending-policy), but at minimum
must be subscribed to the stream.
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00			`# Stream privacy settings`

user docs: Explain streams are similar to channels in stream-permissions. 2018-07-27 03:49:26 +02:00			`Streams are similar to chatrooms, IRC channels, or email lists in that they`
			`determine who receives a message. There are three types of streams in Zulip.`
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00
settings: Migrate to stream_post_policy structure. This commit includes a new `stream_post_policy` setting, by replacing the `is_announcement_only` field from the Stream model, which is done by mirroring the structure of the existing `create_stream_policy`. It includes the necessary schema and database migrations to migrate the is_announcement_only boolean field to stream_post_policy, a smallPositiveInteger field similar to many other settings. This change is done to allow organization administrators to restrict new members from creating and posting to a stream. However, this does not affect admins who are new members. With many tweaks by tabbott to documentation under /help, etc. Fixes #13616. 2020-02-04 21:50:55 +01:00			`* Public: Anyone other than guests can join, and anyone (other`
			`than guests) can view the complete message history without joining.`
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00
			`* Private, shared history: You must be added by a member of the stream. The`
			`complete message history is available as soon as you are added.`

			`* Private, protected history: You must be added by a member of the`
			`stream. You only have access to the messages that are sent after you are added.`

			`## Privacy model for private streams`

			`At a high level:`

			`* Organization admins can see and modify most aspects of a private stream,`
user docs: Update stream-permissions to note message access via bots. 2018-10-20 00:33:09 +02:00			`including the membership and estimated traffic. Admins generally cannot see stream`
			`messages or do things that would indirectly give them access to stream`
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00			`messages, like adding members or changing the stream privacy settings.`

user docs: Update docs to reflect new guests feature. 2018-10-30 06:40:33 +01:00			`* Non-admin members cannot easily see which private streams exist, or interact with`
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00			`them in any way until they are added. Given a stream name, they can figure`
			`out whether a stream with that name exists, but cannot see any other`
			`details about the stream.`

user docs: Update docs to reflect new guests feature. 2018-10-30 06:40:33 +01:00			`* From the perspective of a guest, all streams are private streams, and they`
			`additionally can't add other members to the streams they are subscribed to.`

user docs: Update stream-permissions to note message access via bots. 2018-10-20 00:33:09 +02:00			`There are two situations in which an organization administrator can access`
			`private stream messages:`

			`* Via some types of [data export](/help/export-your-organization).`

			`* Administrators can change the ownership of a bot. If a bot is subscribed`
			`to a private stream, then an administrator can get access to that stream by`
			`taking control of the bot, though the access will be limited to what the`
			`bot can do. (E.g. incoming webhook bots cannot read messages.)`

user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00			`## Detailed permissions`

			`### Public streams`

help: Reorganize stream-permissions table. 2019-03-02 01:02:16 +01:00			`\| \| Org admins \| Members \| Guests`
			`\|--- \|--- \|--- \|---`
			`\| Join \| ✔ \| ✔ \|`
			`\| Unsubscribe \| ◾ \| ◾ \| ◾`
			`\| Add others \| ✔ \| ✔ \|`
			`\| See subscriber list \| ✔ \| ✔ \| ◾`
			`\| See full history \| ✔ \| ✔ \| ◾`
			`\| See estimated traffic \| ✔ \| ✔ \| ◾`
			`\| Post \| ✔ \| ✶ \| ✶`
			`\| Change the privacy \| ✔ \| \|`
			`\| Rename \| ✔ \| \|`
			`\| Edit the description \| ✔ \| \|`
			`\| Remove others \| ✔ \| \|`
			`\| Delete \| ✔ \| \|`

			`✔ Always`

			`◾   If subscribed to the stream`

settings: Migrate to stream_post_policy structure. This commit includes a new `stream_post_policy` setting, by replacing the `is_announcement_only` field from the Stream model, which is done by mirroring the structure of the existing `create_stream_policy`. It includes the necessary schema and database migrations to migrate the is_announcement_only boolean field to stream_post_policy, a smallPositiveInteger field similar to many other settings. This change is done to allow organization administrators to restrict new members from creating and posting to a stream. However, this does not affect admins who are new members. With many tweaks by tabbott to documentation under /help, etc. Fixes #13616. 2020-02-04 21:50:55 +01:00			`✶ [Configurable](/help/stream-sending-policy). Org admins and`
			`Members can, by default, post to any public stream, and Guests can`
			`only post to public streams if they are subscribed.`
user docs: Document admin-only posting in stream-permissions.md. 2018-05-31 22:25:52 +02:00
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00			`### Private streams`


help: Reorganize stream-permissions table. 2019-03-02 01:02:16 +01:00			`\| \| Org admins \| Members \| Guests`
			`\|--- \|--- \|--- \|---`
			`\| Join \| \| \|`
			`\| Unsubscribe \| ◾ \| ◾ \| ◾`
			`\| Add others \| ◾ \| ◾ \|`
			`\| See subscriber list \| ✔ \| ◾ \| ◾`
			`\| See full history \| ✶ \| ✶ \| ✶`
			`\| See estimated traffic \| ✔ \| ◾ \| ◾`
			`\| Post \| ◾ \| ✶ \| ✶`
			`\| Change the privacy \| ◾ \| \|`
			`\| Rename \| ✔ \| \|`
			`\| Edit the description \| ✔ \| \|`
			`\| Remove others \| ✔ \| \|`
			`\| Delete \| ✔ \| \|`
user docs: Update docs to reflect new guests feature. 2018-10-30 06:40:33 +01:00
help: Reorganize stream-permissions table. 2019-03-02 01:02:16 +01:00			`✔ Always`
user docs: Document admin-only posting in stream-permissions.md. 2018-05-31 22:25:52 +02:00
help: Reorganize stream-permissions table. 2019-03-02 01:02:16 +01:00			`◾   If subscribed to the stream`
user docs: Add doc for stream privacy settings. 2018-05-22 19:34:42 +02:00
settings: Migrate to stream_post_policy structure. This commit includes a new `stream_post_policy` setting, by replacing the `is_announcement_only` field from the Stream model, which is done by mirroring the structure of the existing `create_stream_policy`. It includes the necessary schema and database migrations to migrate the is_announcement_only boolean field to stream_post_policy, a smallPositiveInteger field similar to many other settings. This change is done to allow organization administrators to restrict new members from creating and posting to a stream. However, this does not affect admins who are new members. With many tweaks by tabbott to documentation under /help, etc. Fixes #13616. 2020-02-04 21:50:55 +01:00			`✶ [Configurable](/help/stream-sending-policy), but at minimum`
			`must be subscribed to the stream.`