Cloud DevOps Cookbook Part 4-Explore DevOps DirectMail in Python with REST API

This time, we will explore ** Direct Mail ** of ** Alibaba Cloud DevOps ** using ** REST API ** with ** Python **.

• This blog is a translation from the English version. You can check the original from here. We use some machine translation. We would appreciate it if you could point out any translation errors. *

Alibaba Cloud Tech Share, author John Hanley. Tech Share encourages sharing of technical knowledge and best practices within the cloud community Alibaba Cloud Incentive program.

My favorite language for learning rapid prototyping and new cloud services is Python. With Python, most tasks are so simple that you can test your new API in minutes. This allows you to focus on learning without having to worry about the details of how the API works in a particular language. But I'm using C ++ for enterprise-level code that can cost millions of dollars if I make a mistake.

Alibaba's DirectMail does not support Python. PHP, Java and C # are supported. A very common use case for DirectMail is to email dynamic and static websites. Is to deliver. For dynamic websites, PHP is the best choice. For static websites, DirectMail and [Function Compute](https://www.alibabacloud.com/ Integrating product / function-compute? Spm = a2c65.11461447.0.0.38ad725bFhEjCQ) is perfect. However, Function Compute does not support PHP. This means developing in one language on the desktop and in another on the cloud.

So I came up with the idea of using DirectMail's REST API. That means you can use Python to learn how to use the REST API and especially how to create less documented signatures.

DirectMail supports three different interfaces (not all languages are supported).

1、Alibaba REST API 2、Alibaba Cloud SDK 3、Alibaba SMTP Interface In the previous article, I introduced an example of using SDK (Function Compute) in Python. This time, I will focus on the DirectMail REST API and show an example of how it works in Python.

Alibaba Cloud DirectMail REST API

There are several reasons to use the REST API.

1. Understand low-level APIs, parameters and errors. 2, the code space is small. 3, shortened loading and execution time. 4, there are few dependencies.
2. No need to install SDK library on target system. 6, SDK is not available in the target language.

REST API requirements

1. Understand HTTPS, HTTP headers, and HTTP bodies.
2. Understand the difference between HTTP HEAD, DELETE, GET, POST and PUT methods.
3. Understand how to send data for each HTTP method.
4. Understand the API parameters that each HTTP method must contain.
5. Understand how to sign HTTP requests.

Alibaba Cloud Public Parameters

This is a link to Alibaba Documentation for DirectMail Public Parameters.

Comments on the above parameters:

** SignatureNonce **: This parameter has been annoying for some time. At first I thought this was the salt value used when signing HMAC_SHA1. However, it turns out that this is a string generated by uuid.uuid4 () and contained in the header. Repeating the value of this string in a subsequent command will reject the command.

** AccessKeyId **: Creates a new RAM user with DirectMail-only permissions. In this case, you will need both an Access Key and an Access Key Secret for the REST API.

** Timestamp **: It is important that the system date and time are correct. If this time is different from Alibaba's service, the request will be rejected. If possible, use a time service such as NTP for your system.

Alibaba Cloud Direct Mail request parameters

This is a link to Alibaba documentation on DirectMail Request parameters.

Calculate the correct date

# Correctly formatted date and time
now = datetime.datetime.utcnow()

# Date used by the HTTP "Date" header
date = now.strftime("%a, %d %b %Y %H:%M:%S GMT")

# Date used by the API parameter "Timestamp"
utc = now.isoformat(timespec='seconds') + 'Z'

Hosts and endpoints in this example (Singapore-> ap-southeast-1)

# HTTP Host header
host = "dm.ap-southeast-1.aliyuncs.com"

# URL for POST
url = "https://dm.ap-southeast-1.aliyuncs.com/"

Building a parameter list of public parameters

parameters = {}

# Add the DirectMail public request parameters
parameters["Format"] = "json"
parameters["AccessKeyId"] = credentials['AccessKey']
parameters["SignatureMethod"] = "HMAC-SHA1"
parameters["SignatureType"] = ""
parameters["SignatureVersion"] = "1.0"
parameters["SignatureNonce"] = get_uuid()
parameters["Timestamp"] = utc
parameters["Version"] = "2017-06-22"
parameters["RegionId"] = "ap-southeast-1"

Building a parameter list of request parameters

# Add parameters that are always set
parameters["Action"] = "SingleSendMail"
parameters["AddressType"] = "1"
parameters["ReplyToAddress"] = "true"

# Add the DirectMail API parameters
parameters["AccountName"] = dm_account
parameters["FromAlias"] = dm_alias
parameters["ToAddress"] = to_list
parameters["Subject"] = subject
parameters["HtmlBody"] = body
parameters["textBody"] = body_text

Build request string for signature processing

def build_request_string(table):
    """ Build canonical list """
    items = sorted(iter(table.items()), key=lambda d: d[0])
    enc = my_urlencode(items)
    return enc

Precautions regarding request string

Request string parameters must be sorted first. The string is then url-encoded. This means that each key / value pair will have an & character.

The final result looks like the example below, but with a longer length.

AccessKeyId=LTAIQlgy6erobert&AccountName=test%40test.com&Action=SingleSendMail …

Create a signature from the request string

This is a link to Alibaba Documentation on DirectMail Signature.

# Build the request string for the signing process
params = build_request_string(parameters)

# Create the actual string to sign (method = "POST")
stringToSign = method + "&%2F&" + percentEncode(params)

Signature = sign(stringToSign, credentials['AccessKeySecret'])

A program that calls the DirectMail REST API to send an email

Download sendEmail.zip.

############################################################
# Version 1.00
# Date Created: 2018-05-26
# Last Update:  2018-05-27
# https://www.neoprime.io
# Copyright (c) 2018, NeoPrime, LLC
############################################################

""" Alibaba Cloud DirectMail REST API With Signing """

import base64
import datetime
import hmac
import hashlib
import urllib
import uuid
import json
import requests

# My library for processing Alibaba Cloud Services (ACS) credentials
import mycred_acs

# From the DirectMail Console
dm_account = "<enter your value here>"
dm_alias = "<enter your value here>"

debug = 0

def set_connection_logging():
    """ Enable HTTP connection logging """
    if debug is 0:
        return

    import logging
    import http.client as http_client

    http_client.HTTPConnection.debuglevel = 1

    # You must initialize logging, otherwise you'll not see debug output.
    logging.basicConfig()
    logging.getLogger().setLevel(logging.DEBUG)
    requests_log = logging.getLogger("requests.packages.urllib3")
    requests_log.setLevel(logging.DEBUG)
    requests_log.propagate = True
    return

def get_uuid():
    """ return a uuid as a signing nonce """
    return str(uuid.uuid4())

def percentEncode(path):
    """ Encode a URL """
    res = urllib.parse.quote(path)
    res = res.replace('+', '%20')
    res = res.replace('*', '%2A')
    res = res.replace('%7E', '~')
    return res

def my_urlencode(query):
    """ Encode a Query """
    res = urllib.parse.urlencode(query)
    res = res.replace('+', '%20')
    res = res.replace('*', '%2A')
    res = res.replace('%7E', '~')
    return res

def build_request_string(table):
    """ Build canonical list """
    items = sorted(iter(table.items()), key=lambda d: d[0])
    enc = my_urlencode(items)
    return enc

def sign(string, secret):
    """ Sign REST API Request """
    nsecret = secret + '&'

    h = hmac.new(
        bytes(nsecret, "utf-8"),
        bytes(string, "utf-8"),
        hashlib.sha1)

    #sig = base64.b64encode(h.digest())
    sig = str(base64.encodebytes(h.digest()).strip(), "utf-8")
    return sig

def sendEmail(credentials, subject, body, body_text, to_list):
    """ Send an email using Alibaba DirectMail """
    # HTTP Method
    method = "POST"

    # Correctly formatted date and time
    now = datetime.datetime.utcnow()
    date = now.strftime("%a, %d %b %Y %H:%M:%S GMT")
    utc = now.isoformat(timespec='seconds') + 'Z'

    # HTTP Host header
    host = "dm.ap-southeast-1.aliyuncs.com"

    # URL for POST
    url = "https://dm.ap-southeast-1.aliyuncs.com/"

    parameters = {}

    # Add the DirectMail public request parameters
    parameters["Format"] = "json"
    parameters["AccessKeyId"] = credentials['AccessKey']
    parameters["SignatureMethod"] = "HMAC-SHA1"
    parameters["SignatureType"] = ""
    parameters["SignatureVersion"] = "1.0"
    parameters["SignatureNonce"] = get_uuid()
    parameters["Timestamp"] = utc
    #parameters["Version"] = "2015-11-23"
    parameters["Version"] = "2017-06-22"
    parameters["RegionId"] = "ap-southeast-1"

    # Add parameters that are always set
    parameters["Action"] = "SingleSendMail"
    parameters["AddressType"] = "1"
    parameters["ReplyToAddress"] = "true"

    # Add the DirectMail API parameters
    parameters["AccountName"] = dm_account
    parameters["FromAlias"] = dm_alias
    parameters["ToAddress"] = to_list
    parameters["Subject"] = subject
    parameters["HtmlBody"] = body
    parameters["textBody"] = body_text

    # Build the request string for the signing process
    params = build_request_string(parameters)

    # Create the actual string to sign
    stringToSign = method + "&%2F&" + percentEncode(params)

    #print("String to Sign")
    #print(stringToSign)

    Signature = sign(stringToSign, credentials['AccessKeySecret'])
    #print("Signature", Signature)

    parameters["Signature"] = Signature

    headers = {
        'Date': date,
        'Host': host
    }

    set_connection_logging()

    print("Sending Email to", parameters["ToAddress"])
    r = requests.post(url, data=parameters, headers=headers)

    if r.status_code != 200:
        print("Error: Email Send Failed:", r.status_code)
        print(r.text)
        return 1

    #print(r.text)

    result = json.loads(r.text)
    print("Success: Request ID:", result['RequestId'])

    return 0

# Load the Alibaba Cloud Credentials (AccessKey)
cred = mycred_acs.LoadCredentials()

dm_subject = "Welcome to Alibaba Cloud DirectMail"

dm_body = "<h2>Welcome to Alibaba Cloud DirectMail<h2>You are receiving this email as part of a test program.<br /><br />Click for <a href='https://www.neoprime.io/info/alibaba/'>more information<a>.<br /><br /><a href='https://www.alibabacloud.com/'><img src='https://www.neoprime.io/info/alibaba/img/alibaba-600x263.png' alt='Alibaba' width='700'><a>"

dm_body_text = "Welcome to Alibaba Cloud DirectMail\nYou are receiving this email as part of a test program."

dm_to_list = "[email protected], [email protected]

sendEmail(cred, dm_subject, dm_body, dm_body_text, dm_to_list)

Run on Python 3.x: python sendEmail.py

Alibaba document

Alibaba DirectMail Product Page Alibaba DirectMail Documentation Alibaba DirectMail Public parameters Alibaba DirectMail Request parameters Alibaba DirectMail Signature

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