How to Import an Google Firestore Index into Terraform

Import Google Firestore Index with Terraback (recommended)

Terraback reverse-engineers your live infrastructure: it reads the Google Cloud Firestore resource with read-only credentials, generates the HCL, and produces the exact import block. Two commands take you from a live Google Firestore Index to managed Terraform.

terraback scan all gcp --project my-gcp-project

terraback gcp import --method bulk

The Terraform import block

Terraback emits a Terraform 1.5+ import block like the one below. Because the block lives in your configuration, the import is reviewable in a pull request and repeatable across environments.

import {
  to = google_firestore_index.events_by_time
  id = "projects/my-project/databases/(default)/collectionGroups/events/indexes/CICAgJ..."
}

Example google_firestore_index configuration

Here is a realistic Google Firestore Index block. Terraback generates a fuller version from your actual resource attributes; this is a minimal, valid starting point.

resource "google_firestore_index" "events_by_time" {
  project    = "my-project"
  database   = "(default)"
  collection = "events"

  fields {
    field_path = "user_id"
    order      = "ASCENDING"
  }

  fields {
    field_path = "created_at"
    order      = "DESCENDING"
  }
}

Gotchas when importing a Google Firestore Index

• The index_id in the import path is generated by Firestore, not chosen by you; read it from gcloud firestore indexes composite list or the API before importing.
• The default database name is the literal (default), parentheses included, unless you created a named database.
• Composite indexes are immutable: changing the fields, their order, or array_config forces Terraform to delete and recreate the index, which can be slow on large collections.
• fields order and content must match the existing index exactly, including any implicit __name__ ordering Firestore added.

Doing it manually with terraform import

The native approach is to write the google_firestore_index block by hand, then run terraform import google_firestore_index.example <import-id> for every resource, one at a time. That works for a handful of resources, but it does not scale: you author all the HCL yourself and repeat the command for each item. Terraback generates the HCL and the import blocks for your whole account in one pass.

Import other Google Cloud resources