storage-service/storage_service/views/object_view.py

#!/usr/bin/env python3
from flask import jsonify, request, abort, current_app, Response
from flask_classful import FlaskView
from minio.error import BucketAlreadyExists, BucketAlreadyOwnedByYou, ResponseError, NoSuchKey, NoSuchBucket
from marshmallow import ValidationError
from utils import storage
from schemas import DescriptionSchema
import opentracing
from utils import magic_amqp


class ObjectView(FlaskView):
    description_schema = DescriptionSchema(many=False)

    @staticmethod
    def _check_existance(tag: str) -> bool:  # ez aztán igen
        try:
            storage.connection.stat_object(current_app.config['MINIO_BUCKET_NAME'], tag)
        except NoSuchKey:
            return False
        except NoSuchBucket:
            return False

        return True

    def post(self):
        # get important data from the request
        with opentracing.tracer.start_active_span('parseAndValidate'):
            try:
                description = self.description_schema.loads(request.form.get('description'))
            except ValidationError as e:
                return abort(400, str(e))

            # get and validate file
            file = request.files['soundFile']

            if file.content_type != 'audio/wave':
                return abort(400, f"{file.content_type} is not audio/wave")

            if file.content_length <= 0:
                return abort(411, f"Content length for soundFile is not a positive integer or missing.")

        with opentracing.tracer.start_active_span('ensureBuckets'):
            # create bucket if necessary
            try:
                storage.connection.make_bucket(current_app.config['MINIO_BUCKET_NAME'])

            except BucketAlreadyOwnedByYou as err:
                pass
            except BucketAlreadyExists as err:
                pass
                # Everything else should be raised

        with opentracing.tracer.start_active_span('checkExistence'):
            # check for conflict
            if self._check_existance(description['tag']):
                return abort(409)

        with opentracing.tracer.start_active_span(
                'minio.putObject',
                tags={
                    "bucket": current_app.config['MINIO_BUCKET_NAME'],
                    "object_name": description['tag'],
                    "length": file.content_length
                }
        ):
            # poot file into bucket
            try:
                storage.connection.put_object(current_app.config['MINIO_BUCKET_NAME'], description['tag'], file,
                                              file.content_length, content_type=file.content_type)
            except ResponseError:  # TODO: Check if object already exists... somehow
                raise

        with opentracing.tracer.start_active_span('announceSampleReady'):
            magic_amqp.publish({"tag": description['tag']})  # publish sample-ready, so that cnn can start working

        return jsonify({"status": "200"}), 200  # TODO: 200 should be OK but that would be inconsistent with the errors

    def get(self, tag: str):

        # TODO: Validate tag

        try:
            data = storage.connection.get_object(current_app.config['MINIO_BUCKET_NAME'], tag)
        except NoSuchKey:
            return abort(404)

        return Response(data.stream(), mimetype=data.headers['Content-type'])

    def delete(self, tag: str):

        # TODO: Validate tag

        if not self._check_existance(tag):
            return abort(404)

        storage.connection.remove_object(current_app.config['MINIO_BUCKET_NAME'], tag)

        return jsonify({"status": "200"}), 200