How to use GCP's ResourceManager Python client library to get all child Projects under a Folder?

v3 of the Cloud ResourceManager Python API has a list_projects method, but it only returns Projects that are direct children of the given Folder.

For example, you could have sub-folders of that main folder with their own projects and sub-folders and so on.

How can one programmatically get all of the child projects underneath a given folder?

I believe I've solved this using a recursive function, but would appreciate any and all input to improve/refine this. Of course, this is just sample code, and is littered with print statements for verification & debugging, so you will need to modify to suit your needs.

It gets all of the project names and sticks them into a list. For a large organization, you will probably need a better data, file or other structure.

#!/usr/bin/env python3

from google.cloud.resourcemanager_v3 import ProjectsClient, FoldersClient

all_projects = []


def get_folders_and_projects(folder_id):
    """
    Get a list of projects and folders, given a folder ID.
    """
    client = ProjectsClient()
    list_of_projects = client.list_projects(parent=f'folders/{folder_id}')
    print(f"Projects in Folder `{folder_id}`:")
    for project in list_of_projects:
        print(project.project_id)
        all_projects.append(project.project_id)  # Add the project names to a list

    print("")

    client = FoldersClient()
    list_of_folders = client.list_folders(parent=f'folders/{folder_id}')
    for folder in list_of_folders:
        print(f"Folder Name: {folder.display_name}, Folder ID: {folder.name}")
        folder_id = folder.name.strip('folders/')

        # Call the same f'n again to get child projects & folders:
        get_folders_and_projects(folder_id) 


get_folders_and_projects('123456789012')
print(all_projects)

One caveat: this code does not have the ability to start with an organization ID, since that requires a different format to the parent argument, i.e. organizations/org_id

Addition, 25 May 2022: Inspired by @Alssanro's answer that I did not know about prior, I developed some code to use the Cloud Asset API to search for Active projects within a parent.

from google.cloud.asset_v1 import AssetServiceClient, SearchAllResourcesRequest

# The starting parent can be any of the following:
parent = "projects/123456789012"
# parent = "projects/project-name-id"
# parent = "folders/123456789012"
# parent = "organizations/123456789012"

client = AssetServiceClient()

# Construct the request argument
request = SearchAllResourcesRequest(
    scope=parent,
    asset_types=[
        "cloudresourcemanager.googleapis.com/Project",
    ],
    query="state:ACTIVE",
)

# Make the request
paged_results = client.search_all_resources(request=request)

# Handle the response
for response in paged_results:
    project_id = response.name.split("/")[4]
    print(
        f"Project Name: {response.display_name}, Project ID: {project_id}, State: {response.state}, "
    )

Note that I did not use the Resource Manager API as I could not find an easy way to search for/return projects that started at a specific parent AND are active.