Adding Bridges code as git subtree. (#2515)

* Add instructions.

* Squashed 'bridges/' content from commit 345e84a21

git-subtree-dir: bridges
git-subtree-split: 345e84a2146b56628e9888c9f5e129cb40e868a9

* Remove bridges workspace file to avoid confusing Cargo.

* Add some bridges primitives to Polkadot workspace.

* Improve docs.

polkadot/bridges/deployments/run.sh

@@ -0,0 +1,129 @@
+#!/bin/bash
+
+# Script used for running and updating bridge deployments.
+#
+# To deploy a network you can run this script with the name of the network you want to run.
+#
+# `./run.sh poa-rialto`
+#
+# To update a deployment to use the latest images available from the Docker Hub add the `update`
+# argument after the bridge name.
+#
+# `./run.sh rialto-millau update`
+#
+# Once you've stopped having fun with your deployment you can take it down with:
+#
+# `./run.sh rialto-millau stop`
+
+set -xeu
+
+# Since the Compose commands are using relative paths we need to `cd` into the `deployments` folder.
+cd "$( dirname "${BASH_SOURCE[0]}" )"
+
+function show_help () {
+  set +x
+  echo " "
+  echo Error: $1
+  echo " "
+  echo "Usage:"
+  echo "  ./run.sh poa-rialto [stop|update]          Run PoA <> Rialto Networks & Bridge"
+  echo "  ./run.sh rialto-millau [stop|update]       Run Rialto <> Millau Networks & Bridge"
+  echo " "
+  echo "Options:"
+  echo "  --no-monitoring                            Disable monitoring"
+  exit 1
+}
+
+RIALTO=' -f ./networks/rialto.yml'
+MILLAU=' -f ./networks/millau.yml'
+ETH_POA=' -f ./networks/eth-poa.yml'
+MONITORING=' -f ./monitoring/docker-compose.yml'
+
+BRIDGE=''
+NETWORKS=''
+SUB_COMMAND='start'
+for i in "$@"
+do
+  case $i in
+    --no-monitoring)
+      MONITORING=" -f ./monitoring/disabled.yml"
+      shift
+      ;;
+    poa-rialto)
+      BRIDGE=$i
+      NETWORKS+=${RIALTO}
+      NETWORKS+=${ETH_POA}
+      shift
+      ;;
+    rialto-millau)
+      BRIDGE=$i
+      NETWORKS+=${RIALTO}
+      NETWORKS+=${MILLAU}
+      shift
+      ;;
+    start|stop|update)
+      SUB_COMMAND=$i
+      shift
+      ;;
+    *)
+      show_help "Unknown option: $i"
+      ;;
+  esac
+done
+
+if [ -z "$BRIDGE" ]; then
+  show_help "Missing bridge name."
+fi
+
+BRIDGE_PATH="./bridges/$BRIDGE"
+BRIDGE="-f $BRIDGE_PATH/docker-compose.yml"
+COMPOSE_FILES=$BRIDGE$NETWORKS$MONITORING
+
+# Compose looks for .env files in the the current directory by default, we don't want that
+COMPOSE_ARGS="--project-directory . --env-file "
+COMPOSE_ARGS+=$BRIDGE_PATH/.env
+
+# Read and source variables from .env file so we can use them here
+grep -e MATRIX_ACCESS_TOKEN -e WITH_PROXY $BRIDGE_PATH/.env > .env2 && . ./.env2 && rm .env2
+
+if [ ! -z ${MATRIX_ACCESS_TOKEN+x} ]; then
+  sed -i "s/access_token.*/access_token: \"$MATRIX_ACCESS_TOKEN\"/" ./monitoring/grafana-matrix/config.yml
+fi
+
+# Check the sub-command, perhaps we just mean to stop the network instead of starting it.
+if [ "$SUB_COMMAND" == "stop" ]; then
+
+  if [ ! -z ${WITH_PROXY+x} ]; then
+    cd ./reverse-proxy
+    docker-compose down
+    cd -
+  fi
+
+  docker-compose $COMPOSE_ARGS $COMPOSE_FILES down
+
+  exit 0
+fi
+
+# See if we want to update the docker images before starting the network.
+if [ "$SUB_COMMAND" == "update" ]; then
+
+  # Stop the proxy cause otherwise the network can't be stopped
+  if [ ! -z ${WITH_PROXY+x} ]; then
+    cd ./reverse-proxy
+    docker-compose down
+    cd -
+  fi
+
+
+  docker-compose $COMPOSE_ARGS $COMPOSE_FILES pull
+  docker-compose $COMPOSE_ARGS $COMPOSE_FILES down
+  docker-compose $COMPOSE_ARGS $COMPOSE_FILES build
+fi
+
+docker-compose $COMPOSE_ARGS $COMPOSE_FILES up -d
+
+# Start the proxy if needed
+if [ ! -z ${WITH_PROXY+x} ]; then
+  cd ./reverse-proxy
+  docker-compose up -d
+fi