Handle database configuration

Dockerfile

@@ -1,5 +1,6 @@
-FROM ubuntu:16.04
-MAINTAINER Glenn Y. Rolland <glenux@glenux.net>
+FROM debian:bullseye
+LABEL org.opencontainers.image.authors="Glenn Y. Rolland <glenux@glenux.net>"
+LABEL net.glenux.image.version="4.4.1"
 
 # Some ENV variables
 ENV PATH="/mattermost/bin:${PATH}"
@@ -9,16 +10,20 @@ ENV MM_VERSION=4.4.1
 RUN apt-get update \
     && apt-get -y --no-install-recommends install \
                curl jq netcat ca-certificates \
-    && rm -rf /var/lib/apt/lists/* /var/cache/apt/archives/*.deb /var/cache/apt/archives/partial/*.deb /var/cache/apt/*.bin
+    && rm -rf /var/lib/apt/lists/* \
+    	  /var/cache/apt/archives/*.deb \
+    	  /var/cache/apt/archives/partial/*.deb \
+    	  /var/cache/apt/*.bin
 
 # Get Mattermost
 RUN mkdir -p /mattermost/data \
     && curl https://releases.mattermost.com/$MM_VERSION/mattermost-team-$MM_VERSION-linux-amd64.tar.gz | tar -xvz \
-    ; cp /mattermost/config/config.json /config.json.save \
+    && cp /mattermost/config/config.json /config.json.save \
     && rm -rf /mattermost/config/config.json
 
 # Configure entrypoint and command
 COPY entrypoint.sh /
+COPY parseurl.py /
 ENTRYPOINT ["/entrypoint.sh"]
 WORKDIR /mattermost/bin
 CMD ["platform"]

entrypoint.sh

@@ -0,0 +1,100 @@
+#!/bin/bash
+
+set -u 
+set -e
+
+# Function to generate a random salt
+generate_salt() {
+  tr -dc 'a-zA-Z0-9' < /dev/urandom | fold -w 48 | head -n 1
+}
+
+# Update configuration file according to value 
+config_set() {
+	local value="$1"
+	local file="$2"
+
+    jq "$value" "$file" > "$file.tmp"
+    mv "$file.tmp" "$file"
+}
+
+# Parse environment variables 
+chmod +x /parseurl.py
+/parseurl.py MM_DB_
+eval "$(/parseurl.py MM_DB_)"
+
+# Read environment variables or set default values
+DB_HOST=${DB_HOST:-db}
+DB_PORT_NUMBER=${DB_PORT_NUMBER:-5432}
+MM_USERNAME=${MM_USERNAME:-mmuser}
+MM_PASSWORD=${MM_PASSWORD:-mmuser_password}
+MM_DBNAME=${MM_DBNAME:-mattermost}
+MM_CONFIG=${MM_CONFIG:-/mattermost/config/config.json}
+
+if [ "${1:0:1}" = '-' ]; then
+    set -- platform "$@"
+fi
+
+if [ "$1" = 'platform' ]; then
+  # Check CLI args for a -config option
+  for ARG in "$@";
+  do
+      case "$ARG" in
+          -config=*)
+              MM_CONFIG=${ARG#*=};;
+      esac
+  done
+
+  if [ ! -f "$MM_CONFIG" ]
+  then
+    # If there is no configuration file, create it with some default values
+    echo "No configuration file" "$MM_CONFIG"
+    echo "Creating a new one"
+    # Copy default configuration file
+    cp /config.json.save "$MM_CONFIG"
+
+    # Substitute some parameters with jq
+    config_set '.ServiceSettings.ListenAddress = ":80"' "$MM_CONFIG" 
+    config_set '.LogSettings.EnableConsole = false' "$MM_CONFIG" 
+    config_set '.LogSettings.ConsoleLevel = "INFO"' "$MM_CONFIG" 
+    config_set '.FileSettings.Directory = "/mattermost/data/"' "$MM_CONFIG"
+    config_set '.FileSettings.EnablePublicLink = true' "$MM_CONFIG" 
+    config_set ".FileSettings.PublicLinkSalt = \"$(generate_salt)\"" "$MM_CONFIG"
+    config_set '.EmailSettings.SendEmailNotifications = false' "$MM_CONFIG"
+    config_set '.EmailSettings.FeedbackEmail = ""' "$MM_CONFIG"
+    config_set '.EmailSettings.SMTPServer = ""' "$MM_CONFIG" 
+    config_set '.EmailSettings.SMTPPort = ""' "$MM_CONFIG"
+    config_set ".EmailSettings.InviteSalt = \"$(generate_salt)\"" "$MM_CONFIG"
+    config_set ".EmailSettings.PasswordResetSalt = \"$(generate_salt)\"" "$MM_CONFIG"
+    config_set '.RateLimitSettings.Enable = true' "$MM_CONFIG"
+    config_set '.SqlSettings.DriverName = "postgres"' "$MM_CONFIG"
+    config_set ".SqlSettings.AtRestEncryptKey = \"$(generate_salt)\"" "$MM_CONFIG" 
+  else
+    echo "Using existing config file" "$MM_CONFIG"
+  fi
+
+  # Configure database access
+  if [ -z "$MM_SQLSETTINGS_DATASOURCE" ]
+  then
+    echo -ne "Configure database connection..."
+    export MM_SQLSETTINGS_DATASOURCE="postgres://$MM_USERNAME:$MM_PASSWORD@$DB_HOST:$DB_PORT_NUMBER/$MM_DBNAME?sslmode=disable&connect_timeout=10"
+    echo OK
+  else
+    echo "Using existing database connection"
+  fi
+
+  # Wait for database to be reachable
+  echo "Wait until database $DB_HOST:$DB_PORT_NUMBER is ready..."
+  until nc -z "$DB_HOST" "$DB_PORT_NUMBER"
+  do
+    sleep 1
+  done
+
+  # Wait another second for the database to be properly started.
+  # Necessary to avoid "panic: Failed to open sql connection pq: the database system is starting up"
+  sleep 1
+
+  echo "Starting platform"
+fi
+
+exec "$@"
+

parseurl.py

@@ -0,0 +1,63 @@
+#!/usr/bin/env python
+
+import sys
+import os
+from urlparse import urlparse
+
+prefix = sys.argv[1]
+# print os.environ.keys
+uri_str = os.environ['DATABASE_URL']
+uri = urlparse(uri_str)
+
+db_netloc = uri.netloc 
+
+db_credential = None
+db_username = None
+db_password = None
+db_host = None
+db_port = None
+
+if db_netloc.find("@") >= 0 :
+  tmp_arr1 = db_netloc.split('@')
+  db_credential = tmp_arr1[0]
+  db_host = tmp_arr1[1]
+
+if db_credential and db_credential.find(':') >= 0 :
+  tmp_arr2 = db_credential.split(':')
+  db_username = tmp_arr2[0]
+  db_password = tmp_arr2[1]
+
+if db_host and db_host.find(':') >= 0 :
+  tmp_arr3 = db_host.split(':')
+  db_host = tmp_arr3[0]
+  db_port = tmp_arr3[1]
+
+db_path = uri.path
+db_scheme = uri.scheme 
+db_query = uri.query
+db_fragment = uri.fragment
+
+if db_scheme :
+  print(prefix + 'SCHEME=' + db_scheme)
+
+if db_username :
+  print(prefix + 'USERNAME=' + db_username)
+
+if db_password :
+  print(prefix + 'PASSWORD=' + db_password)
+
+if db_host :
+  print(prefix + 'HOST=' + db_host)
+
+if db_port :
+  print(prefix +  'PORT=' + db_port)
+
+if db_path :
+  print(prefix + 'NAME=' + db_path[1:])
+
+if db_query :
+  print(prefix + 'QUERY=' + db_query)
+
+if db_fragment :
+  print(prefix + 'FRAGMENT=' + db_fragment)
+