new: [nextcloud] add compatibility with mysql database

nextcloud/hooks/mysql_database-relation-joined

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+. lib/common
+
+set -e
+
+PASSWORD="$(relation-get password)"
+USER="$(relation-get user)"
+DBNAME="$(relation-get dbname)"
+
+
+## This check adds purely arbitrary limits to what could be a password
+## if we need to open that more, just consider the next script where we'll
+## need to write in a PHP structure, or in YAML structure.
+
+## Note that here, "[]" chars are not accepted just because it doesn't seem evident
+## to test for those in bash.
+if ! [[ "$PASSWORD" =~ ^[a-zA-Z0-9~\`\&+=@\#^\*/\\_%\$:\;\!?.,\<\>{}()\"\'|-]*$ ]]; then
+     err "Invalid password chosen for mysql database."
+     exit 1
+fi
+
+## if config is not existent
+if [ -e "$CONFIGFILE" ] && grep "^  'dbuser' => '" "$CONFIGFILE" >/dev/null; then
+
+    ## 'occ' can't be used as it will try to connect to mysql before running and
+    ## will fail if user/password is not correct
+
+    ## We need to get through bash, and sed interpretation, then PHP single quoted strings.
+    quoted_user="${USER//\\/\\\\\\\\\\}"
+    quoted_user="${quoted_user//\'/\\\\\'}"
+    quoted_password="${PASSWORD//\\/\\\\\\\\\\}"
+    quoted_password="${quoted_password//\'/\\\\\'}"
+    sed -ri "s/^(  'dbuser' => ')(.*)(',)$/\1${quoted_user}\3/g;\
+             s/^(  'dbpassword' => ')(.*)(',)$/\1${quoted_password}\3/g;" "$CONFIGFILE"
+else
+
+    ## These variable are not used by current docker image after first install
+
+    config-add "\
+services:
+  $MASTER_BASE_SERVICE_NAME:
+    environment:
+      MYSQL_HOST: $MASTER_TARGET_SERVICE_NAME
+      MYSQL_DATABASE: $DBNAME
+      MYSQL_PASSWORD: $PASSWORD
+      MYSQL_USER: $USER
+"
+fi
+
+info "Configured $SERVICE_NAME code for $TARGET_SERVICE_NAME access."

nextcloud/metadata.yml

@@ -14,6 +14,13 @@ uses:
     auto: summon
     solves:
       database: "main storage"
+  mysql-database:
+    #constraint: required | recommended | optional
+    #auto: pair | summon | none ## default: pair
+    constraint: optional
+    auto: pair
+    solves:
+      database: "main storage"
   web-proxy:
     #constraint: required | recommended | optional
     #auto: pair | summon | none ## default: pair