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# Setting up Messenger bridging via Mautrix Meta (optional)

The playbook can install and configure the [mautrix-meta](https://github.com/mautrix/meta) Messenger/Instagram bridge for you.

Since this bridge component can bridge to both [Messenger](https://messenger.com/) and [Instagram](https://instagram.com/) and you may wish to do both at the same time, the playbook makes it available via 2 different Ansible roles (`matrix-bridge-mautrix-meta-messenger` and `matrix-bridge-mautrix-meta-instagram`). The latter is a reconfigured copy of the first one (created by `just rebuild-mautrix-meta-instagram` and `bin/rebuild-mautrix-meta-instagram.sh`).

This documentation page only deals with the bridge's ability to bridge to Facebook Messenger. For bridging to Instagram, see [Setting up Instagram bridging via Mautrix Meta](configuring-playbook-bridge-mautrix-meta-instagram.md).

## Prerequisites

### Migrating from the old mautrix-facebook bridge

If you've been using the [mautrix-facebook](./configuring-playbook-bridge-mautrix-facebook.md) bridge, it's possible to migrate the database using [instructions from the bridge documentation](https://docs.mau.fi/bridges/go/meta/facebook-migration.html) (advanced).

Then you may wish to get rid of the Facebook bridge. To do so, send a `clean-rooms` command to the management room with the old bridge bot (`@facebookbot:example.com`). It gives you a list of portals and groups of portals you may purge. Proceed with sending commands like `clean recommended`, etc.

Then, consider disabling the old bridge in your configuration, so it won't recreate the portals when you receive new messages.

**Note**: the user ID of the new bridge bot is `@messengerbot:example.com`, not `@facebookbot:example.com`. After disabling the old bridge, its bot user will stop responding to a command.

### Enable Appservice Double Puppet (optional)

If you want to set up [Double Puppeting](https://docs.mau.fi/bridges/general/double-puppeting.html) (hint: you most likely do) for this bridge automatically, you need to have enabled [Appservice Double Puppet](configuring-playbook-appservice-double-puppet.md) service for this playbook.

For details about configuring Double Puppeting for this bridge, see the section below: [Set up Double Puppeting](#-set-up-double-puppeting)

## Adjusting the playbook configuration

To enable the bridge, add the following configuration to your `inventory/host_vars/matrix.example.com/vars.yml` file:

```yaml
matrix_mautrix_meta_messenger_enabled: true
```

Before proceeding to [re-running the playbook](./installing.md), you may wish to adjust the configuration further. See below.

### Bridge mode

As mentioned above, the [mautrix-meta](https://github.com/mautrix/meta) bridge supports multiple modes of operation.

The bridge can pull your Messenger messages via 3 different methods:

- (`facebook`) Facebook via `facebook.com`
- (`facebook-tor`) Facebook via `facebookwkhpilnemxj7asaniu7vnjjbiltxjqhye3mhbshg7kx5tfyd.onion` ([Tor](https://www.torproject.org/)) - does not currently proxy media downloads
- (default) (`messenger`) Messenger via `messenger.com` - usable even without a Facebook account

You may switch the mode via the `matrix_mautrix_meta_messenger_meta_mode` variable. The playbook defaults to the `messenger` mode, because it's most universal (every Facebook user has a Messenger account, but the opposite is not true).

Note that switching the mode (especially between `facebook*` and `messenger`) will intentionally make the bridge use another database (`matrix_mautrix_meta_facebook` or `matrix_mautrix_meta_messenger`) to isolate the 2 instances. Switching between Tor and non-Tor may be possible without dataloss, but your mileage may vary. Before switching to a new mode, you may wish to de-configure the old one (send `help` to the bridge bot and unbridge your portals, etc.).

### Bridge permissions

By default, any user on your homeserver will be able to use the bridge.

Different levels of permission can be granted to users:

- `relay` - Allowed to be relayed through the bridge, no access to commands
- `user` - Use the bridge with puppeting
- `admin` - Use and administer the bridge

The permissions are following the sequence: nothing < `relay` < `user` < `admin`.

The default permissions are set via `matrix_mautrix_meta_messenger_bridge_permissions_default` and are somewhat like this:

```yaml
matrix_mautrix_meta_messenger_bridge_permissions_default:
  '*': relay
  example.com: user
  '{{ matrix_admin }}': admin
```

If you don't define the `matrix_admin` in your configuration (e.g. `matrix_admin: @user:example.com`), then there's no admin by default.

You may redefine `matrix_mautrix_meta_messenger_bridge_permissions_default` any way you see fit, or add extra permissions using `matrix_mautrix_meta_messenger_bridge_permissions_custom` like this:

```yaml
matrix_mautrix_meta_messenger_bridge_permissions_custom:
  '@YOUR_USERNAME:example.com': admin
```

You may wish to look at `roles/custom/matrix-bridge-mautrix-meta-messenger/templates/config.yaml.j2` to find more information on the permissions settings and other options you would like to configure.

## Installing

After configuring the playbook, run it with [playbook tags](playbook-tags.md) as below:

<!-- NOTE: let this conservative command run (instead of install-all) to make it clear that failure of the command means something is clearly broken. -->
```sh
ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,ensure-matrix-users-created,start
```

**Notes**:

- The `ensure-matrix-users-created` playbook tag makes the playbook automatically create the bot's user account.

- The shortcut commands with the [`just` program](just.md) are also available: `just install-all` or `just setup-all`

  `just install-all` is useful for maintaining your setup quickly ([2x-5x faster](../CHANGELOG.md#2x-5x-performance-improvements-in-playbook-runtime) than `just setup-all`) when its components remain unchanged. If you adjust your `vars.yml` to remove other components, you'd need to run `just setup-all`, or these components will still remain installed.

## Usage

You then need to start a chat with `@messengerbot:example.com` (where `example.com` is your base domain, not the `matrix.` domain). Note that the user ID of the bridge's bot is not `@facebookbot:example.com`.

You then need to send a `login` command and follow the bridge bot's instructions.

Given that the bot is configured in `messenger` [bridge mode](#bridge-mode) by default, you will need to log in to [messenger.com](https://messenger.com/) (not `facebook.com`!) and obtain the cookies from there as per [the bridge's authentication instructions](https://docs.mau.fi/bridges/go/meta/authentication.html).

### 💡 Set up Double Puppeting

After successfully enabling bridging, you may wish to set up [Double Puppeting](https://docs.mau.fi/bridges/general/double-puppeting.html) (hint: you most likely do).

To set it up, you have 2 ways of going about it.

#### Method 1: automatically, by enabling Appservice Double Puppet

The bridge automatically performs Double Puppeting if [Appservice Double Puppet](configuring-playbook-appservice-double-puppet.md) service is configured and enabled on the server for this playbook.

This is the recommended way of setting up Double Puppeting, as it's easier to accomplish, works for all your users automatically, and has less of a chance of breaking in the future.

#### Method 2: manually, by asking each user to provide a working access token

When using this method, **each user** that wishes to enable Double Puppeting needs to follow the following steps:

- retrieve a Matrix access token for yourself. Refer to the documentation on [how to do that](obtaining-access-tokens.md).

- send the access token to the bot. Example: `login-matrix MATRIX_ACCESS_TOKEN_HERE`

- make sure you don't log out the session for which you obtained an access token some time in the future, as that would break the Double Puppeting feature
