google cloud: downloading as an CSV

问题

I have a download button that should return a users CSV. The code for it below:

class StartCSVHandler(ThreeScaleResourceHandler):
    """ Starts generating a user's CSV file """
    allowed_methods = ('new',)
    requires_input = False
    def post(self, *args, **kwargs):
        user = self.current_user()
        if not user:
            self.abort(401, detail=ERROR_NOT_AUTHORIZED)
        task_url = '/jobs/users/%s/data/csv' % user.key()
        taskqueue.add(url=task_url, queue_name='users')
        return {}

def generate_data_from_query(query, user, format, handler, filename, mission=None):

    batch_size = 500
    cursor = None
    spottings = []
    count = 0

    mime_type = 'text/csv' if format == CSV_FORMAT else 'text/xml'

    timestamp = '%0.6f' % time.time()

    gcs_filename_template = '/{bucket}/{user}/{timestamp}/{filename}'

    from global_config import config

    gcs_filename = gcs_filename_template.format(
        bucket='project-noah-backups',
        # bucket=config['cloudstorage']['export_files_bucket'],
        user=str(user.key()),
        timestamp=timestamp,
        filename=filename
        )

    logging.debug(str(user.key()))
    f = cloudstorage.open(gcs_filename, mode='w', content_type=mime_type)

    # blobstore_file_name = files.blobstore.create(mime_type=mime_type, _blobinfo_uploaded_filename=filename.encode('utf-8'))

    while True:
        if format == CSV_FORMAT:
            writer = utils.UnicodeWriter(f)
            if count == 0:
                writer.writerow(csv_display_names)
        elif format == KML_FORMAT and count == 0:
            f.write(template.render('spotting_export_pre.kml', {}))

        if cursor:
            query.with_cursor(cursor)
        spottings = query.fetch(batch_size)

        if format == CSV_FORMAT:
            dicts = [s.as_dict() for s in spottings]
            logging.debug(dicts)
            for spotting_dict in dicts:
                writer.writerow([spotting_dict[k] for k in csv_keys])
        elif format == KML_FORMAT:
            output = template.render('spotting_export_mid.kml', {'spottings' : spottings, 'server_url' : utils.server_url(handler.request)})
            f.write(output.encode('utf-8'))

        cursor = query.cursor()
        logging.info('written spottings %d to %d' % (count, count + len(spottings)))

        count += len(spottings)
        if not mission:
            push_to_beacon_user(user, {'format':format,'progress':count})
        else:
            push_to_beacon_user_mission(user, mission, {'format':format,'progress':count})

        if len(spottings) < batch_size:
            break


    if format == KML_FORMAT:
        f.write(template.render('spotting_export_post.kml', {}))

    blob_key = BlobKey(blobstore.create_gs_key(u'/gs' + gcs_filename))
    logging.debug(blob_key)
    return blob_key


def generate_data_from_user_spottings(user, format, handler):
    filename = u'My-Spottings.%s' % format
    # query = user.mySpottings
    query = user.mySpottings
    logging.debug(query)
    return generate_data_from_query(query, user, format, handler, filename)

class GenerateUserDataHandler(NoahHandler):
    def post(self, user_key=None, format=None):
        if not user_key:
            return
        user = NoahUser.get(user_key)
        if not user:
            return
        if format not in (CSV_FORMAT, KML_FORMAT):
            return


        blob_key = generate_data_from_user_spottings(user, format, self)
        user = NoahUser.get(user_key)
        if format == CSV_FORMAT:
            if user.csv:
                user.csv.delete()
            user.csv = blob_key
            user.put()
        elif format == KML_FORMAT:
            if user.kml:
                user.kml.delete()
            user.kml = blob_key
            user.put()

        logging.debug(user.recent_spottings)
        logging.debug(str(blob_key))
        push_to_beacon_user(user, {'format': format,'url':'/data?key=%s' % str(blob_key)})


class ThreeScaleResourceHandler(ResourceHandler):


    @three_scale_authenticate
    def get(self, *args, **kwargs):
        super(ThreeScaleResourceHandler, self).get(*args, **kwargs)

    @three_scale_authenticate
    def post(self, *args, **kwargs):
        super(ThreeScaleResourceHandler, self).post(*args, **kwargs)

    @three_scale_authenticate
    def put(self, *args, **kwargs):
        super(ThreeScaleResourceHandler, self).put(*args, **kwargs)    

    @three_scale_authenticate
    def delete(self, *args, **kwargs):
        super(ThreeScaleResourceHandler, self).delete(*args, **kwargs)

This should download users data in the form of an CSV. The problem i am getting is two fold; firstly, the end point that this generates is '/api/v1/users/me/data/csv' and when visiting it, i receive the following error

{"error": {"title": "Unauthorized", "status": 401, "message": "You are not authorized to perform that action. Please use the api_key parameter with your registered key."}}

Secondly, the link it provides for the user to save cannot be found:

http://localhost:8080/data?key=encoded_gs_file:cHJvamVjdC1ub2FoLWJhY2t1cHMvYWdoa1pYWi1UbTl1WlhJVkN4SUlUbTloYUZWelpYSVlnSUNBZ0lDQWdBb00vMTU4MTAxODk3My4wODgyODEvTXktU3BvdHRpbmdzLmNzdg==

I am not entirely sure what i need to correct.

回答1:

firstly, the end point that this generates is '/api/v1/users/me/data/csv' and when visiting it, i receive the following error: {"error": {"title": "Unauthorized", "status": 401, "message": "You are not authorized to perform that action. Please use the api_key parameter with your registered key."}}

Which handler in your code snippet handles /api/v1/users/me/data/csv? Is it StartCSVHandler? Are you sure it isn't being thrown because of this line? self.abort(401, detail=ERROR_NOT_AUTHORIZED)

Secondly, the link it provides for the user to save cannot be found: http://localhost:8080/data?key=encoded_gs_file:cHJvamVjdC1ub2FoLWJhY2t1cHMvYWdoa1pYWi1UbTl1WlhJVkN4SUlUbTloYUZWelpYSVlnSUNBZ0lDQWdBb00vMTU4MTAxODk3My4wODgyODEvTXktU3BvdHRpbmdzLmNzdg==

In what way? like you are trying to find the file on your machine or this link is throwing a 404?

On your localhost, encoded_gs_file files can be found here: http://localhost:8000/blobstore

If it's a 404, then what does your handler for /data do? It doesnt look like it's in your code snippet

来源：https://stackoverflow.com/questions/60102619/google-cloud-downloading-as-an-csv