feat: add the ability to constrain memory on service start/clone

Refs dokku/dokku-redis#86

README.md

@@ -68,6 +68,7 @@ flags:
 - `-C|--custom-env "USER=alpha;HOST=beta"`: semi-colon delimited environment variables to start the service with
 - `-i|--image IMAGE`: the image name to start the service with
 - `-I|--image-version IMAGE_VERSION`: the image version to start the service with
+- `-m|--memory MEMORY`: container memory limit (default: unlimited)
 - `-p|--password PASSWORD`: override the user-level service password
 - `-r|--root-password PASSWORD`: override the root-level service password
 
@@ -425,6 +426,7 @@ flags:
 - `-C|--custom-env "USER=alpha;HOST=beta"`: semi-colon delimited environment variables to start the service with
 - `-i|--image IMAGE`: the image name to start the service with
 - `-I|--image-version IMAGE_VERSION`: the image version to start the service with
+- `-m|--memory MEMORY`: container memory limit (default: unlimited)
 - `-p|--password PASSWORD`: override the user-level service password
 - `-r|--root-password PASSWORD`: override the root-level service password
 

functions

@@ -60,6 +60,10 @@ service_create() {
     echo "" >"$SERVICE_ROOT/ENV"
   fi
 
+  if [[ -n "$SERVICE_MEMORY" ]]; then
+    echo "$SERVICE_MEMORY" >"$SERVICE_ROOT/SERVICE_MEMORY"
+  fi
+
   write_database_name "$SERVICE"
   plugn trigger service-action post-create "$SERVICE"
   service_create_container "$SERVICE"
@@ -75,7 +79,13 @@ service_create_container() {
   local DATABASE_NAME="$(get_database_name "$SERVICE")"
   local PREVIOUS_ID
 
-  ID=$(docker run --name "$SERVICE_NAME" -v "$SERVICE_HOST_ROOT/data:/var/lib/postgresql/data" -e "POSTGRES_PASSWORD=$PASSWORD" --env-file="$SERVICE_ROOT/ENV" -d --restart always --label dokku=service --label dokku.service=postgres "$PLUGIN_IMAGE:$PLUGIN_IMAGE_VERSION")
+  [[ -f "$SERVICE_ROOT/SERVICE_MEMORY" ]] && SERVICE_MEMORY="$(cat "$SERVICE_ROOT/SERVICE_MEMORY")"
+  if [[ -n "$SERVICE_MEMORY" ]]; then
+    MEMORY_LIMIT="--memory=${SERVICE_MEMORY}m"
+  fi
+
+  # shellcheck disable=SC2086
+  ID=$(docker run --name "$SERVICE_NAME" $MEMORY_LIMIT -v "$SERVICE_HOST_ROOT/data:/var/lib/postgresql/data" -e "POSTGRES_PASSWORD=$PASSWORD" --env-file="$SERVICE_ROOT/ENV" -d --restart always --label dokku=service --label dokku.service=postgres "$PLUGIN_IMAGE:$PLUGIN_IMAGE_VERSION")
   echo "$ID" >"$SERVICE_ROOT/ID"
 
   dokku_log_verbose_quiet "Waiting for container to be ready"

subcommands/clone

@@ -13,6 +13,7 @@ service-clone-cmd() {
   #F -C|--custom-env "USER=alpha;HOST=beta", semi-colon delimited environment variables to start the service with
   #F -i|--image IMAGE, the image name to start the service with
   #F -I|--image-version IMAGE_VERSION, the image version to start the service with
+  #F -m|--memory MEMORY, container memory limit (default: unlimited)
   #F -p|--password PASSWORD, override the user-level service password
   #F -r|--root-password PASSWORD, override the root-level service password
   declare desc="create container <new-name> then copy data from <name> into <new-name>"

subcommands/create

@@ -21,6 +21,7 @@ service-create-cmd() {
   #F -C|--custom-env "USER=alpha;HOST=beta", semi-colon delimited environment variables to start the service with
   #F -i|--image IMAGE, the image name to start the service with
   #F -I|--image-version IMAGE_VERSION, the image version to start the service with
+  #F -m|--memory MEMORY, container memory limit (default: unlimited)
   #F -p|--password PASSWORD, override the user-level service password
   #F -r|--root-password PASSWORD, override the root-level service password
   declare desc="create a $PLUGIN_SERVICE service"