feat: add Python example for downloading a dashboard as CSV (#1389)

Adds a Python example using QueryTasks to download each of the elements
of a dashboard as CSV inside a folder. Pulling the query status for each
task.

Fixes #1363

examples/python/README.md

@@ -28,6 +28,9 @@ The full details of all Looker API 4.0 endpoints are listed in [Looker Docs](htt
 
 - [Kill all running queries](kill_queries.py)
 
+## QueryTask : Manage Query Tasks
+- [Download dashboard tiles as CSVs][download_dashboard_csv.py]
+
 ## RenderTask : Manage Render Tasks
 
 - [Download dashboard tile in specified format](download_tile.py)

examples/python/download_dashboard_csv.py

@@ -0,0 +1,115 @@
+""" Given a dashboard id, download each of its tiles as csv files
+
+    $ python download_dashboard_csv.py <dashboard_id>
+    Note: dashboard_id is required
+
+Example:
+    $ python download_dashboard_csv.py 1234
+"""
+
+import os
+import time
+import sys
+import textwrap
+from typing import Sequence
+from looker_sdk.sdk.api40.models import (
+    DashboardElement,
+    WriteCreateQueryTask,
+    ResultFormat,
+)
+
+import looker_sdk
+
+sdk = looker_sdk.init40("../../looker.ini")
+
+
+def main():
+    dashboard_id = sys.argv[1] if len(sys.argv) > 1 else ""
+
+    if not dashboard_id:
+        raise Exception(
+            textwrap.dedent(
+                """
+                Please provide: <dashboard_id>"""
+            )
+        )
+
+    download_dashboard_csv(dashboard_id)
+
+
+def get_all_dashboard_elements(dashboard_id: str) -> Sequence[DashboardElement]:
+    """Get all dashboard elements by dashboard id."""
+    elements = sdk.dashboard_dashboard_elements(dashboard_id, fields="query")
+    if len(elements) == 0:
+        raise Exception(f'Dashboard "{dashboard_id}" not found')
+    return elements
+
+
+def save_data_to_csv(data: str, folder: str, filename: str):
+    with open(os.path.join(folder, f"{filename}.csv"), "w") as f:
+        f.write(data)
+
+
+def create_folder(folder_name):
+    if not os.path.exists(folder_name):
+        os.mkdir(folder_name)
+    return os.path.join(os.getcwd(), folder_name)
+
+
+def download_dashboard_csv(dashboard_id: str):
+    elements = sdk.dashboard_dashboard_elements(dashboard_id, fields="query")
+
+    query_tasks_ids = []
+
+    # Create Async Query Task for each element of the dashboard
+    for element in elements:
+        if not element.query or not element.query.id:
+            continue
+
+        query_id = element.query.id
+        body = WriteCreateQueryTask(
+            query_id=query_id, result_format=ResultFormat("csv")
+        )
+
+        query_task = sdk.create_query_task(
+            body=body,
+        )
+
+        if query_task.id:
+            query_tasks_ids.append(query_task.id)
+
+    completed_async_tasks = []
+
+    create_folder(dashboard_id)
+
+    # Do a polling for completed Query Tasks
+    # Any Query Task that completes is downloaded and saved to CSV
+    # Polling will be triggered every second. Will stop after 1 min
+    retries = 60
+    while (len(query_tasks_ids) > 0 or len(completed_async_tasks) > 0) and retries > 0:
+        # Get status for each task_id and move to completed list if "complete"
+        for task_id in query_tasks_ids.copy():
+            query_task_info = sdk.query_task(task_id)
+            status = query_task_info.status
+
+            if status == "complete":
+                completed_async_tasks.append(task_id)
+                query_tasks_ids.remove(task_id)
+            elif status == "error":
+                print(f"Query Task {task_id} failed with an error")
+                return
+
+        # Download results for all completed pending tasks and write to csv per task
+        for completed_task_id in completed_async_tasks.copy():
+            results = sdk.query_task_results(completed_task_id)
+            save_data_to_csv(results, dashboard_id, completed_task_id)
+            completed_async_tasks.remove(completed_task_id)
+
+        if len(query_tasks_ids) > 0 or len(completed_async_tasks) > 0:
+            retries -= 1
+            time.sleep(1)
+
+    print("Process complete")
+
+
+main()