# Installing Dendrite

Dendrite can be run in one of two configurations:

 * A cluster of individual components, dealing with different aspects of the
   Matrix protocol (see [WIRING.md](./WIRING.md)). Components communicate with
   one another via [Apache Kafka](https://kafka.apache.org).

 * A monolith server, in which all components run in the same process. In this
   configuration, Kafka can be replaced with an in-process implementation
   called [naffka](https://github.com/matrix-org/naffka).

## Requirements

 - Go 1.11+
 - Postgres 9.5+
 - For Kafka (optional if using the monolith server):
   - Unix-based system (https://kafka.apache.org/documentation/#os)
   - JDK 1.8+ / OpenJDK 1.8+
   - Apache Kafka 0.10.2+ (see [scripts/install-local-kafka.sh](scripts/install-local-kafka.sh) for up-to-date version numbers)


## Setting up a development environment

Assumes Go 1.10+ and JDK 1.8+ are already installed and are on PATH.

```bash
# Get the code
git clone https://github.com/matrix-org/dendrite
cd dendrite

# Build it
./build.sh
```

If using Kafka, install and start it (c.f. [scripts/install-local-kafka.sh](scripts/install-local-kafka.sh)):
```bash
MIRROR=http://apache.mirror.anlx.net/kafka/0.10.2.0/kafka_2.11-0.10.2.0.tgz

# Only download the kafka if it isn't already downloaded.
test -f kafka.tgz || wget $MIRROR -O kafka.tgz
# Unpack the kafka over the top of any existing installation
mkdir -p kafka && tar xzf kafka.tgz -C kafka --strip-components 1

# Start the zookeeper running in the background.
# By default the zookeeper listens on localhost:2181
kafka/bin/zookeeper-server-start.sh -daemon kafka/config/zookeeper.properties

# Start the kafka server running in the background.
# By default the kafka listens on localhost:9092
kafka/bin/kafka-server-start.sh -daemon kafka/config/server.properties
```

On MacOS, you can use [homebrew](https://brew.sh/) for easier setup of kafka

```bash
brew install kafka
brew services start zookeeper
brew services start kafka
```

## Configuration

### Postgres database setup

Dendrite requires a postgres database engine, version 9.5 or later.

* Create role:
  ```bash
  sudo -u postgres createuser -P dendrite     # prompts for password
  ```
* Create databases:
  ```bash
  for i in account device mediaapi syncapi roomserver serverkey federationsender publicroomsapi appservice naffka; do
      sudo -u postgres createdb -O dendrite dendrite_$i
  done
  ```

(On macOS, omit `sudo -u postgres` from the above commands.)

### Crypto key generation

Generate the keys:

```bash
# Generate a self-signed SSL cert for federation:
test -f server.key || openssl req -x509 -newkey rsa:4096 -keyout server.key -out server.crt -days 3650 -nodes -subj /CN=localhost

# generate ed25519 signing key
test -f matrix_key.pem || ./bin/generate-keys -private-key matrix_key.pem
```

### Configuration

Create config file, based on `dendrite-config.yaml`. Call it `dendrite.yaml`. Things that will need editing include *at least*:
* `server_name`
* `database/*` (All lines in the database section must have the username and password of the user created with the `createuser` command above. eg:`dendrite:password@localhost`)


## Starting a monolith server

It is possible to use 'naffka' as an in-process replacement to Kafka when using
the monolith server. To do this, set `use_naffka: true` in `dendrite.yaml` and uncomment
the necessary line related to naffka in the `database` section. Be sure to update the 
database username and password if needed.

The monolith server can be started as shown below. By default it listens for
HTTP connections on port 8008, so point your client at
`http://localhost:8008`. If you set `--tls-cert` and `--tls-key` as shown
below, it will also listen for HTTPS connections on port 8448.

```bash
./bin/dendrite-monolith-server --tls-cert=server.crt --tls-key=server.key
```

## Starting a multiprocess server

The following contains scripts which will run all the required processes in order to point a Matrix client at Dendrite. Conceptually, you are wiring together to form the following diagram:

```

                                         /media   +---------------------------+
                      +----------->+------------->| dendrite-media-api-server |
                      ^            ^              +---------------------------+
                      |            |            :7774
                      |            |
                      |            |
                      |            |   /directory +----------------------------------+
                      |            |   +--------->| dendrite-public-rooms-api-server |<========++
                      |            |   |          +----------------------------------+         ||
                      |            |   |        :7775    |                                     ||
                      |            |   |    +<-----------+                                     ||
                      |            |   |    |                                                  ||
                      |            |   | /sync    +--------------------------+                 ||
                      |            |   +--------->| dendrite-sync-api-server |<================++
                      |            |   |    |     +--------------------------+                 ||
                      |            |   |    |   :7773    |         ^^                          ||
Matrix      +------------------+   |   |    |            |         ||    client_data           ||
Clients --->| client-api-proxy |-------+    +<-----------+         ++=============++           ||
            +------------------+   |   |    |                                     ||           ||
          :8008                    |   | CS API   +----------------------------+  ||           ||
                                   |   +--------->| dendrite-client-api-server |==++           ||
                                   |        |     +----------------------------+               ||
                                   |        |   :7771    |                                     ||
                                   |        |            |                                     ||
                                   |        +<-----------+                                     ||
                                   |        |                                                  ||
                                   |        |                                                  ||
                                   |        |           +----------------------+    room_event ||
                                   |        +---------->| dendrite-room-server |===============++
                                   |        |           +----------------------+               ||
                                   |        |         :7770                                    ||
                                   |        |                      ++==========================++
                                   |        +<------------+        ||
                                   |        |             |        VV
                                   |        |     +-----------------------------------+              Matrix
                                   |        |     | dendrite-federation-sender-server |------------> Servers
                                   |        |     +-----------------------------------+
                                   |        |   :7776
                                   |        |
                       +---------->+        +<-----------+
                       |                                 |
Matrix      +----------------------+  SS API  +--------------------------------+
Servers --->| federation-api-proxy |--------->| dendrite-federation-api-server |
            +----------------------+          +--------------------------------+
          :8448                             :7772


   A --> B  = HTTP requests (A = client, B = server)
   A ==> B  = Kafka (A = producer, B = consumer)
```

### Run a client api proxy

This is what Matrix clients will talk to. If you use the script below, point your client at `http://localhost:8008`.

```bash
./bin/client-api-proxy \
--bind-address ":8008" \
--client-api-server-url "http://localhost:7771" \
--sync-api-server-url "http://localhost:7773" \
--media-api-server-url "http://localhost:7774" \
--public-rooms-api-server-url "http://localhost:7775" \
```

### Run a client api

This is what implements message sending. Clients talk to this via the proxy in order to send messages.

```bash
./bin/dendrite-client-api-server --config=dendrite.yaml
```

(If this fails with `pq: syntax error at or near "ON"`, check you are using at least postgres 9.5.)

### Run a room server

This is what implements the room DAG. Clients do not talk to this.

```bash
./bin/dendrite-room-server --config=dendrite.yaml
```

### Run a sync server

This is what implements `/sync` requests. Clients talk to this via the proxy in order to receive messages.

```bash
./bin/dendrite-sync-api-server --config dendrite.yaml
```

### Run a media server

This implements `/media` requests. Clients talk to this via the proxy in order to upload and retrieve media.

```bash
./bin/dendrite-media-api-server --config dendrite.yaml
```

### Run public room server

This implements `/directory` requests. Clients talk to this via the proxy in order to retrieve room directory listings.

```bash
./bin/dendrite-public-rooms-api-server --config dendrite.yaml
```

### Run a federation api proxy

This is what Matrix servers will talk to. This is only required if you want to support federation.

```bash
./bin/federation-api-proxy \
--bind-address ":8448" \
--federation-api-url "http://localhost:7772" \
--media-api-server-url "http://localhost:7774" \
```

### Run a federation api server

This implements federation requests. Servers talk to this via the proxy in
order to send transactions.  This is only required if you want to support
federation.

```bash
./bin/dendrite-federation-api-server --config dendrite.yaml
```

### Run a federation sender server

This sends events from our users to other servers.  This is only required if
you want to support federation.

```bash
./bin/dendrite-federation-sender-server --config dendrite.yaml
```

### Run an appservice server 

This sends events from the network to [application
services](https://matrix.org/docs/spec/application_service/unstable.html)
running locally.  This is only required if you want to support running
application services on your homeserver.

```bash
./bin/dendrite-appservice-server --config dendrite.yaml
```
