:plugin: google_pubsub :type: input :default_codec: plain /////////////////////////////////////////// START - GENERATED VARIABLES, DO NOT EDIT! /////////////////////////////////////////// :version: %VERSION% :release_date: %RELEASE_DATE% :changelog_url: %CHANGELOG_URL% :include_path: ../../../../logstash/docs/include /////////////////////////////////////////// END - GENERATED VARIABLES, DO NOT EDIT! /////////////////////////////////////////// [id="plugins-{type}s-{plugin}"] === Google_pubsub input plugin include::{include_path}/plugin_header.asciidoc[] ==== Description Author: Eric Johnson Date: 2016-06-01 Copyright 2016 Google Inc. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. Google deps This is a https://github.com/elastic/logstash[Logstash] input plugin for https://cloud.google.com/pubsub/[Google Pub/Sub]. The plugin can subscribe to a topic and ingest messages. The main motivation behind the development of this plugin was to ingest https://cloud.google.com/logging/[Stackdriver Logging] messages via the https://cloud.google.com/logging/docs/export/using_exported_logs[Exported Logs] feature of Stackdriver Logging. ==== Prerequisites You must first create a Google Cloud Platform project and enable the Google Pub/Sub API. If you intend to use the plugin ingest Stackdriver Logging messages, you must also enable the Stackdriver Logging API and configure log exporting to Pub/Sub. There is plentiful information on https://cloud.google.com/ to get started: - Google Cloud Platform Projects and https://cloud.google.com/docs/overview/[Overview] - Google Cloud Pub/Sub https://cloud.google.com/pubsub/[documentation] - Stackdriver Logging https://cloud.google.com/logging/[documentation] ==== Cloud Pub/Sub Currently, this module requires you to create a `topic` manually and specify it in the logstash config file. You must also specify a `subscription`, but the plugin will attempt to create the pull-based `subscription` on its own. All messages received from Pub/Sub will be converted to a logstash `event` and added to the processing pipeline queue. All Pub/Sub messages will be `acknowledged` and removed from the Pub/Sub `topic` (please see more about https://cloud.google.com/pubsub/overview#concepts)[Pub/Sub concepts]. It is generally assumed that incoming messages will be in JSON and added to the logstash `event` as-is. However, if a plain text message is received, the plugin will return the raw text in as `raw_message` in the logstash `event`. ==== Authentication You have two options for authentication depending on where you run Logstash. 1. If you are running Logstash outside of Google Cloud Platform, then you will path to the JSON private key file in your config in `json_key_file` setting. If you don't want to upload the file and use its content as a string, then add the content of JSON private key in `json_key_file_content` setting. You must assign sufficient roles to the Service Account to create a subscription and to pull messages from the subscription. Learn more about GCP Service Accounts and IAM roles here: - Google Cloud Platform IAM https://cloud.google.com/iam/[overview] - Creating Service Accounts https://cloud.google.com/iam/docs/creating-managing-service-accounts[overview] - Granting Roles https://cloud.google.com/iam/docs/granting-roles-to-service-accounts[overview] 2. If you are running Logstash on a Google Compute Engine instance, you may opt to use Application Default Credentials. In this case, you will not need to specify a JSON private key file in your config. ==== Stackdriver Logging (optional) If you intend to use the logstash plugin for Stackdriver Logging message ingestion, you must first manually set up the Export option to Cloud Pub/Sub and the manually create the `topic`. Please see the more detailed instructions at, https://cloud.google.com/logging/docs/export/using_exported_logs [Exported Logs] and ensure that the https://cloud.google.com/logging/docs/export/configure_export#manual-access-pubsub[necessary permissions] have also been manually configured. Logging messages from Stackdriver Logging exported to Pub/Sub are received as JSON and converted to a logstash `event` as-is in https://cloud.google.com/logging/docs/export/using_exported_logs#log_entries_in_google_pubsub_topics[this format]. ==== Sample Configuration Below is a copy of the included `example.conf-tmpl` file that shows a basic configuration for this plugin. [source,ruby] ---------------------------------- input { google_pubsub { # Your GCP project id (name) project_id => "my-project-1234" # The topic name below is currently hard-coded in the plugin. You # must first create this topic by hand and ensure you are exporting # logging to this pubsub topic. topic => "logstash-input-dev" # The subscription name is customizeable. The plugin will attempt to # create the subscription (but use the hard-coded topic name above). subscription => "logstash-sub" # If you are running logstash within GCE, it will use # Application Default Credentials and use GCE's metadata # service to fetch tokens. However, if you are running logstash # outside of GCE, you will need to specify the service account's # JSON key file below. #json_key_file => "/home/erjohnso/pkey.json" # Should the plugin attempt to create the subscription on startup? # This is not recommended for security reasons but may be useful in # some cases. #create_subscription => false } } output { stdout { codec => rubydebug } } ---------------------------------- ==== Metadata and Attributes The original Pub/Sub message is preserved in the special Logstash `[@metadata][pubsub_message]` field so you can fetch: * Message attributes * The origiginal base64 data * Pub/Sub message ID for de-duplication * Publish time You MUST extract any fields you want in a filter prior to the data being sent to an output because Logstash deletes `@metadata` fields otherwise. See the PubsubMessage https://cloud.google.com/pubsub/docs/reference/rest/v1/PubsubMessage[documentation] for a full description of the fields. Example to get the message ID: [source,ruby] ---------------------------------- input {google_pubsub {...}} filter { mutate { add_field => { "messageId" => "%{[@metadata][pubsub_message][messageId]}" } } } output {...} ---------------------------------- [id="plugins-{type}s-{plugin}-options"] ==== Google_pubsub Input Configuration Options This plugin supports the following configuration options plus the <> described later. [cols="<,<,<",options="header",] |======================================================================= |Setting |Input type|Required | <> |a valid filesystem path|No | <> |<>|Yes | <> |<>|Yes | <> |<>|Yes | <> |<>|Yes | <> |<>|No | <> |<>|No |======================================================================= Also see <> for a list of options supported by all input plugins.   [id="plugins-{type}s-{plugin}-json_key_file"] ===== `json_key_file` * Value type is <> * There is no default value for this setting. If logstash is running within Google Compute Engine, the plugin will use GCE's Application Default Credentials. Outside of GCE, you will need to specify a Service Account JSON key file. [id="plugins-{type}s-{plugin}-max_messages"] ===== `max_messages` * This is a required setting. * Value type is <> * Default value is `5` The maximum number of messages returned per request. The Pub/Sub system may return fewer than the number specified. [id="plugins-{type}s-{plugin}-project_id"] ===== `project_id` * This is a required setting. * Value type is <> * There is no default value for this setting. Google Cloud Project ID (name, not number). [id="plugins-{type}s-{plugin}-subscription"] ===== `subscription` * This is a required setting. * Value type is <> * There is no default value for this setting. [id="plugins-{type}s-{plugin}-topic"] ===== `topic` * This is a required setting. * Value type is <> * There is no default value for this setting. Google Cloud Pub/Sub Topic and Subscription. Note that the topic must be created manually with Cloud Logging pre-configured export to PubSub configured to use the defined topic. The subscription will be created automatically by the plugin. [id="plugins-{type}s-{plugin}-include_metadata"] ===== `include_metadata` * Value type is <> * Default value is `false`. If set true, will include the full message data in the `[@metadata][pubsub_message]` field. [id="plugins-{type}s-{plugin}-create_subscription"] ===== `create_subscription` added[1.2.0] * Value type is <> * Default value is `false`. If true, the plugin will try to create the subscription before publishing. Note: this requires additional permissions to be granted to the client and is _not_ recommended for most use-cases. [id="plugins-{type}s-{plugin}-common-options"] include::{include_path}/{type}.asciidoc[] :default_codec!: