main.py

# Copyright 2018 Google LLC
#
# 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.

# [START gae_python37_bigquery]
import concurrent.futures

import flask
from google.cloud import bigquery


app = flask.Flask(__name__)
bigquery_client = bigquery.Client()


@app.route("/")
def main():
    query_job = bigquery_client.query(
        """
        SELECT
        CONCAT(
            'https://stackoverflow.com/questions/',
            CAST(id as STRING)) as url,
        view_count
        FROM `bigquery-public-data.stackoverflow.posts_questions`
        WHERE tags like '%google-bigquery%'
        ORDER BY view_count DESC
        LIMIT 10
    """
    )

    return flask.redirect(
        flask.url_for(
            "results",
            project_id=query_job.project,
            job_id=query_job.job_id,
            location=query_job.location,
        )
    )


@app.route("/results")
def results():
    project_id = flask.request.args.get("project_id")
    job_id = flask.request.args.get("job_id")
    location = flask.request.args.get("location")

    query_job = bigquery_client.get_job(
        job_id,
        project=project_id,
        location=location,
    )

    try:
        # Set a timeout because queries could take longer than one minute.
        results = query_job.result(timeout=30)
    except concurrent.futures.TimeoutError:
        return flask.render_template("timeout.html", job_id=query_job.job_id)

    return flask.render_template("query_result.html", results=results)


if __name__ == "__main__":
    # This is used when running locally only. When deploying to Google App
    # Engine, a webserver process such as Gunicorn will serve the app. This
    # can be configured by adding an `entrypoint` to app.yaml.
    app.run(host="127.0.0.1", port=8080, debug=True)
# [END gae_python37_bigquery]