Cloud storage

# -*- coding: utf-8 -*-

# stdlib
import html

# xmltodict
import xmltodict

# Azure
from azure.storage.blob import BlobServiceClient

# Zato
from zato.server.service import Service

class UploadBlob(Service):
    """ Uploads a file to Azure Blob Storage.
    """
    name = 'azure.blob.upload'

    input = 'folder', 'filename', 'content'

    def handle(self) -> 'None':

        folder = self.request.input.folder
        filename = self.request.input.filename
        content = self.request.input.content

        # Credentials come from configuration ..
        account_url = self.config.azure.storage.account_url
        account_key = self.config.azure.storage.account_key
        container_name = self.config.azure.storage.container_name

        # .. the client connects to the storage account ..
        blob_service = BlobServiceClient(
            account_url=account_url,
            credential=account_key
        )

        # .. and the blob is addressed inside its container.
        container = blob_service.get_container_client(container_name)
        blob = container.get_blob_client(f'{folder}/{filename}')

        try:
            blob.upload_blob(content)

            self.response.payload = {
                'status': 'uploaded',
                'path': f'{folder}/{filename}'
            }
            self.logger.info('%s uploaded to Azure Blob Storage', filename)

        except Exception as e:

            # Azure reports errors as XML embedded in the exception's text
            error_str = html.unescape(str(e))
            xml_start = error_str.find('<?xml')
            xml_end = error_str.rfind('</Error>') + len('</Error>')

            if xml_start >= 0 and xml_end > xml_start:
                xml_content = error_str[xml_start:xml_end]
                error_response = xmltodict.parse(xml_content)
                self.logger.error('Azure error: %s', error_response['Error']['Code'])
                self.response.payload = error_response
            else:
                self.logger.error('Upload failed, e:`%s`', e)
                self.response.payload = {'error': str(e)}

# -*- coding: utf-8 -*-

# Azure
from azure.storage.blob import BlobServiceClient

# Zato
from zato.server.service import Service

class DownloadBlob(Service):
    name = 'azure.blob.download'

    input = 'folder', 'filename'

    def handle(self) -> 'None':

        folder = self.request.input.folder
        filename = self.request.input.filename

        account_url = self.config.azure.storage.account_url
        account_key = self.config.azure.storage.account_key
        container_name = self.config.azure.storage.container_name

        blob_service = BlobServiceClient(
            account_url=account_url,
            credential=account_key
        )

        container = blob_service.get_container_client(container_name)
        blob = container.get_blob_client(f'{folder}/{filename}')

        # The blob's bytes become a downloadable response
        download_stream = blob.download_blob()
        content = download_stream.readall()

        self.response.payload = content
        self.response.headers['Content-Disposition'] = f'attachment; filename={filename}'

# -*- coding: utf-8 -*-

# Azure
from azure.storage.blob import BlobServiceClient

# Zato
from zato.server.service import Service

class ListBlobs(Service):
    name = 'azure.blob.list'

    input = '-prefix'

    def handle(self) -> 'None':

        # The optional prefix narrows the listing, an empty one lists everything
        prefix = self.request.input.prefix

        account_url = self.config.azure.storage.account_url
        account_key = self.config.azure.storage.account_key
        container_name = self.config.azure.storage.container_name

        blob_service = BlobServiceClient(
            account_url=account_url,
            credential=account_key
        )

        container = blob_service.get_container_client(container_name)

        blobs = []
        for blob in container.list_blobs(name_starts_with=prefix):
            blobs.append({
                'name': blob.name,
                'size': blob.size,
                'last_modified': blob.last_modified.isoformat()
            })

        self.response.payload = {'blobs': blobs, 'count': len(blobs)}

# -*- coding: utf-8 -*-

# Boto
import boto3

# Zato
from zato.server.service import Service

class UploadToS3(Service):
    """ Uploads a file to an S3 bucket.
    """
    name = 'aws.s3.upload'

    input = 'bucket', 'key', 'content'

    def handle(self) -> 'None':

        bucket = self.request.input.bucket
        key = self.request.input.key
        content = self.request.input.content

        # Credentials come from configuration
        s3 = boto3.client(
            's3',
            aws_access_key_id=self.config.aws.access_key_id,
            aws_secret_access_key=self.config.aws.secret_access_key,
            region_name=self.config.aws.region
        )

        s3.put_object(Bucket=bucket, Key=key, Body=content)

        self.response.payload = {
            'status': 'uploaded',
            'bucket': bucket,
            'key': key
        }

# -*- coding: utf-8 -*-

# Boto
import boto3

# Zato
from zato.server.service import Service

class DownloadFromS3(Service):
    name = 'aws.s3.download'

    input = 'bucket', 'key'

    def handle(self) -> 'None':

        bucket = self.request.input.bucket
        key = self.request.input.key

        s3 = boto3.client(
            's3',
            aws_access_key_id=self.config.aws.access_key_id,
            aws_secret_access_key=self.config.aws.secret_access_key,
            region_name=self.config.aws.region
        )

        response = s3.get_object(Bucket=bucket, Key=key)
        content = response['Body'].read()

        # The object's own name becomes the download's filename
        filename = key.split('/')[-1]

        self.response.payload = content
        self.response.headers['Content-Disposition'] = f'attachment; filename={filename}'

# -*- coding: utf-8 -*-

# stdlib
import json
from datetime import datetime

# Zato
from zato.server.service import Service

class StoreWorkflowData(Service):
    """ Persists one workflow step's data as a JSON blob.
    """
    name = 'workflow.data.store'

    input = 'workflow_id', 'step', 'data'

    def handle(self) -> 'None':

        workflow_id = self.request.input.workflow_id
        step = self.request.input.step
        data = self.request.input.data

        # The blob carries the step's data with its metadata ..
        blob_content = json.dumps({
            'workflow_id': workflow_id,
            'step': step,
            'timestamp': datetime.now().isoformat(),
            'data': data
        }, ensure_ascii=False).encode('utf-8')

        # .. filed under the current date, one file per workflow step.
        folder = f'workflows/{datetime.now().date()}'
        filename = f'{workflow_id}-{step}.json'

        self.invoke('azure.blob.upload',
            folder=folder,
            filename=filename,
            content=blob_content)

        self.response.payload = {'stored': f'{folder}/{filename}'}