使用Python的Amazon SNS
我正在尝试使用亚马逊的SNS服务。这个API非常简单，是基于REST的。我似乎在调用时遇到了签名部分的问题。API的示例是：
http://sns.us-east-1.amazonaws.com/
?Subject=My%20first%20message
&TopicArn=arn%3Aaws%3Asns%3Aus-east-1%3A698519295917%3AMy-Topic
&Message=Hello%20world%21
&Action=Publish
&SignatureVersion=2
&SignatureMethod=HmacSHA256
&Timestamp=2010-03-31T12%3A00%3A00.000Z
&AWSAccessKeyId=AKIAJHS4T6XPF7XIURNA
&Signature=9GZysQ4Jpnz%2BHklqM7VFTvEcjR2LIUtn6jW47054xxE%3D
我一直在参考关于签名的API文档，所以我尝试了：
from time import strftime,gmtime,time
import urllib2
import hmac
import hashlib
import base64
import string
def publichSNSMsg(Subject,TopicArn,Message,AWSAccessKeyId,privatekey):
#http://docs.amazonwebservices.com/AWSSimpleQueueService/2008-01-01/SQSDeveloperGuide/
amzsnshost = 'sns.us-east-1.amazonaws.com'
values = {'Subject' : Subject,
'TopicArn' : TopicArn,
'Message' :Message,
'Timestamp' : strftime("%Y-%m-%dT%H:%M:%S.000Z", gmtime(time())),
'AWSAccessKeyId' : AWSAccessKeyId,
'Action' : 'Publish',
'SignatureVersion' : '2',
'SignatureMethod' : 'HmacSHA256',
}
amazquote=lambda v: urllib2.quote(v).replace('%7E','~')
cannqs=string.join(["%s=%s"%(amazquote(key),amazquote(values[key])) for key in sorted(values.keys(),key=str.lower)],'&')
string_to_sign=string.join(["GET",amzsnshost,"/",cannqs],'\n')
sig=base64.encodestring(hmac.new(privatekey,string_to_sign,hashlib.sha1).digest())
querystring = "%s&Signature=%s"%(cannqs,amazquote(sig))
url="http://%s/?%s"%(amzsnshost,querystring)
try:
return urllib2.urlopen(url).read()
except urllib2.HTTPError, exception:
return "Error %s (%s):\n%s"%(exception.code,exception.msg,exception.read())
但是得到了：
<ErrorResponse xmlns="http://sns.amazonaws.com/doc/2010-03-31/">
<Error>
<Type>Sender</Type>
<Code>SignatureDoesNotMatch</Code>
<Message>The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details.</Message>
</Error>
<RequestId>8d6e5a41-dafb-11df-ac33-f981dc4e6c50</RequestId>
</ErrorResponse>
有没有什么建议？
3 个回答
1
我建议你使用boto3来处理SNS（简单通知服务）。你可以在这里找到相关的文档：http://boto3.readthedocs.io/en/latest/reference/services/sns.html。下面的代码片段可以用来获取签名，格式是JSON。
import boto3
from django.views.decorators.csrf import csrf_exempt
topic_arn = <your topic>
client = boto3.client('sns',region_name="us-west-2")
#Call this to publish
def sns_publish(arg1,arg2):
response = client.publish(
TopicArn=topic_arn,
Message=arg2,
Subject=arg2
)
#Function to subscribe to topic
@csrf_exempt
def sns_parse(request):
print request.body.decode('utf-8')
if request.method == "POST":
response = json.loads(request.body.decode('utf-8'))
type = response.get('Type')
if type == 'Subscription':
print(type)
return("Subscription URL: "+<Url obtained>)
elif type == 'Notification':
return HttpResponse(type.get('Signature'))
else:
return HttpResponse('Not a POST object')
这只是一个模板代码，不过，boto3确实很有帮助。
1
我觉得这个例子非常有用，所以我把它用C#重写了一遍。因为AWS没有针对WP7的SNS库，也许这对某些人会有帮助：https://gist.github.com/2705156
4