Pubsub2Inbox is a versatile, multi-purpose tool to handle Pub/Sub messages and turn them into email, API calls, CS objects, files or almost anything. It's based on an extendable framework consisting of input and output processors. Input processors can enrich the incoming messages with details (for example, fetching the budget from Cloud Billing Budgets API, calling different GCP API or third party services). Multiple input and output processors can be chained together in a pipeline.

Pubsub2Inbox is written in Python 3.8 and can be deployed as a Cloud Function v1/v2 or as a Cloud Run function easily. To guard credentials and other sensitive information, the tool can fetch its YAML configuration from Google Cloud Secret Manager.

The tool also supports templating of emails, messages and other parameters through Jinja2 templating, with additional filters and functions added.

Please note: You cannot connect to SMTP port 25 from GCP. Use alternative ports 465 or 587, or connect via Serverless VPC Connector to your own mailservers.

Also check out Json2Pubsub, a complementary any-webhook-to-Pub/Sub tool!

Out of the box, you'll have the following functionality available as examples:

Available input processors are:

• budget.py: retrieves details from Cloud Billing Budgets API and presents.
• scc.py: enriches Cloud Security Command Center findings notifications.
• bigquery.py: queries from BigQuery datasets.
• genericjson.py: Parses message data as JSON and presents it to output processors.
• recommendations.py: Retrieves recommendations and insights from the Recommender API.
• groups.py: Retrieves Cloud Identity Groups
• directory.py: Retrieves users, groups, group members and group settings
• monitoring.py: Retrieves time series data from Cloud Ops Monitoring
• projects.py: Searches or gets GCP project details
• cai.py: Fetch assets from Cloud Asset Inventory
• shellscript.py: Run any binary or shell script and parse the output (JSON, YAML, CSV, TSV, ...)
• transcode.py: Transcode media using Transcoder API.
• dns.py: Issue change requests to Cloud DNS.
• secret.py: Fetches (additional) secrets from Secret Manager.
• github.py: List, get or create issues and comments in GitHub.
• download.py: Download files using HTTP, FTP and SFTP.
• git.py: Clone repositories via HTTP or SSH.
• clouddeploy.py: Work with releases and rollouts on Cloud Deploy.
• setvariable.py: Set global variables.
• computeengine.py: Manipulate Compute Engine resources.
• loadbalancing.py: Change load balancer settings.
• cloudrun.py: Query Cloud Run things (like jobs).
• logging.py: List entries from Cloud Logging.
• opsgenie.py: OpsGenie alert and incident management.
• docker.py: Push, pull and delete Docker images from a Docker registry.

For full documentation of permissions, processor input and output parameters, see PROCESSORS.md.

Please note that the input processors have some IAM requirements to be able to pull information from GCP:

• Resend mechanism and concurrency control (see below)
  • Storage Object Admin (roles/storage.objectAdmin)
• Signed URL generation (see filters/strings.py:generate_signed_url)
  • Storage Admin on the bucket (roles/storage.admin)

Available output processors are:

• mail.py: can send HTML and/or text emails via SMTP gateways, SendGrid or MS Graph API (Graph API implementation lacks attachment support)
• gcs.py: can create objects on GCS from any inputs.
• webhook.py: can send arbitrary HTTP requests, optionally with added OAuth2 bearer token from GCP.
• gcscopy.py: copies files between buckets.
• logger.py: Logs message in Cloud Logging.
• pubsub.py: Sends one or more Pub/Sub messages.
• bigquery.py: Sends output to a BigQuery table via a load job.
• scc.py: Sends findings to Cloud Security Command Center.
• twilio.py: Sends SMS messages via Twilio API.
• groupssettings.py: Updates Google Groups settings.
• chat.py: Send messages to Google Chat.
• slack.py: Send messages (and other things) to Slack API.
• delay.py: Delay processing by pausing execution for specified time.

Please note that the output processors have some IAM requirements to be able to pull information from GCP:

• mail.py
  • Group membership expansion requires following the instructions at Groups API: Authenticating as a service account without domain-wide delegation to grant permissions to the service account the function is running under.
  • In addition, the service account that the script runs under will need to have roles/iam.serviceAccountTokenCreator on itself when running in Cloud Function/Cloud Run (for Directory API scoped tokens).

For more documentation, see output.md.

Pubsub2Inbox is configured through a YAML file (for examples, see the examples/ directory).

The YAML file is structured of the following top level keys:

• pipeline: a list of processors and/or outputs to run in sequence.
  • type: what processor or output to run (eg. processor.genericjson or output.logger)
  • variables: Additional variables to set before invoking this processor/output.
  • description: A description that gets printed in the logs.
  • config: configuration of the processor or output
  • runIf: if this evaluates to empty, the processor/output is not run
  • stopIf: if this evalues to non-empty, the processing is stopped immediately (before the processor/output is run)
  • ignoreOn: (deprecated) skips reprocessing of messages, see below:
    • bucket: Cloud Storage bucket to store reprocessing markers (zero-length files), has to exist
    • period: textual presentation of the period after which a message can be reprocessed (eg. 2 days)
    • key: the object reprocessing marker name (filename), if not set, it is the message and its properties hashed, otherwise you can specify a Jinja expression
  • canFail: if set to true, the task can fail but processing will still continue
  • output: the output variable for processors (some processors accept a single string, some a list of keys and values)
• onError: allows you to call one output if any of the pipeline tasks fail fatally
• canFail: any task in the pipeline can fail fatally, but the message will still be marked processed
• maximumMessageAge: a textual representation of maximum age of a message that can be processed (set to skip to ignore)
• globals: a dictionary of variables that is evaluated before starting the pipeline, useful for things like localization, or other configuration parameters that get repeatedly used in the pipeline configuration
• macros: a list of Jinja macros to be made available in the pipeline (see example)
• ignoreOn: skips reprocessing of messages, see below:
  • bucket: Cloud Storage bucket to store reprocessing markers (zero-length files), has to exist
  • period: textual presentation of the period after which a message can be reprocessed (eg. 2 days)
  • key: the object reprocessing marker name (filename), if not set, it is the message and its properties hashed, otherwise you can specify a Jinja expression
• concurrency: skips processing of messages by limiting concurrent instances of the function, see below:
  • bucket: Cloud Storage bucket to store zero-length concurrency lock file
  • period: textual presentation of the period after which the lock is considered invalid (eg. 2 days, leave unset if no period)
  • file: the concurrency lock file name (defaults to pubsub2inbox.lock)
  • defer: allow Pub/Sub to retry the message (defaults to false)

For example of a modern pipeline, see shell script example or test configs.

For legacy configuration details, see LEGACY.

Sample Terraform module is provided in main.tf, variables.tf and outputs.tf. Pass the following parameters in when using as a module:

• project_id (string): where to deploy the function
• organization_id (number): organization ID (for organization level permissions)
• function_name (string): name for the Cloud Function
• function_roles (list(string)): list of curated permissions roles for the function (eg. scc, budgets, bigquery_reader, bigquery_writer, cai, recommender, monitoring)
• pubsub_topic (string): Pub/Sub topic in the format of projects/project-id/topics/topic-id which the Cloud Function should be triggered on
• region (string, optional): region where to deploy the function
• secret_id (string, optional): name for the Cloud Secrets Manager secrets (defaults to function_name)
• config_file (string, optional): function configuration YAML file location (defaults to config.yaml)
• service_account (string, optional): service account name for the function (defaults to function_name)
• bucket_name (string, optional): bucket where to host the Cloud Function archive (defaults to cf-pubsub2inbox)
• bucket_location (string, optional): location of the bucket for Cloud Function archive (defaults to EU)
• helper_bucket_name (string, optional): specify an additional Cloud Storage bucket where the service account is granted storage.objectAdmin on
• function_timeout (number, optional): a timeout for the Cloud Function (defaults to 240 seconds)
• retry_minimum_backoff (string, optional): minimum backoff time for exponential backoff retries in Cloud Run. Defaults to 10s.
• retry_maximum_backoff (string, optional): maximum backoff time for exponential backoff retries in Cloud Run. Defaults to 600s.
• vpc_connector (string, optional): ID of the serverless VPC Connector for the Cloud Function
• cloud_run (boolean, optional): deploy via Cloud Run instead of Cloud Function. Defaults to false. If set to true, also specify cloud_run_container.
• cloud_run_container (string, optional): container image to deploy on Cloud Run. See previous parameter.
• cloud_functions_v2 (boolean, optional): deploy using Cloud Functions V2. Defaults to false. Recommended to set true.
• use_local_files (boolean, optional): use local files when deploying. Defaults to true.
• local_files_path (str, optional): sets the path where to fetch the function files.
• log_level (int, optional): set log level, defaults to 10 (debug).

For manual deployment option, see LEGACY.

A prebuilt container image is available on this page. The container is signed and the signature can be verified with cosign for example:

cosign verify --key container-signature.pub ghcr.io/googlecloudplatform/pubsub2inbox:latest

A Dockerfile has been provided for building the container. You can build the image locally and push it to for example Artifact Registry.

docker build -t europe-west4-docker.pkg.dev/$PROJECT_ID/pubsub2inbox/pubsub2inbox . 
docker push europe-west4-docker.pkg.dev/$PROJECT_ID/pubsub2inbox/pubsub2inbox

The provided Terraform scripts can deploy the code as a Cloud Function or Cloud Run. To enable Cloud Run deployment, build and push the image and set cloud_run and cloud_run_container parameters (see the parameter descriptions above).

This is a simple example of deploying the function straight from the repository:

locals {
  project_id    = <YOUR-PROJECT-ID>
  region        = "europe-west1"
  helper_bucket = true
}

module "pubsub-topic" {
  source     = "github.com/GoogleCloudPlatform/cloud-foundation-fabric//modules/pubsub"
  project_id = local.project_id
  name       = "pubsub-example-1"
  iam = {}
}

# This optional helper bucket is used to store resend objects for example
module "helper-bucket" {
  count      = local.helper_bucket ? 1 : 0
  source     = "github.com/GoogleCloudPlatform/cloud-foundation-fabric//modules/gcs"
  project_id = local.project_id
  name       = format("pubsub2inbox-helper-%s", module.pubsub2inbox.name)
}

module "pubsub2inbox" {
  source = "github.com/GoogleCloudPlatform/pubsub2inbox"

  project_id = local.project_id
  region     = local.region

  function_name = "function-example-1"
  pubsub_topic  = module.pubsub-topic.id

  config_file     = "<YOUR-CONFIGURATION-FILE>.yaml"
  # Downloads the release from Github
  use_local_files = false

  bucket_name        = format("pubsub2inbox-source-%s", module.pubsub2inbox.name)
  bucket_location    = local.region
  helper_bucket_name = local.helper_bucket ? module.helper-bucket.0.bucket.name : ""

  cloud_functions_v2 = true

  # Add additional permissions for the service account here
  function_roles = []
}

Run the command:

# make docs

Run the command:

# make test

To test against a real cloud project, set PROJECT_ID environment variable.