sns

Lambda event

class awsmate.sns.LambdaMessageEvent(event_object: dict)

Bases: LambdaEvent

Mapping of the input event received by an AWS Lambda function triggered by AWS SNS.

Parameters:: event_object (dict) – The parameter event received by the AWS Lambda function handler.
Raises:: TypeError – If event_object is not a dict.

Examples

>>> def lambda_handler(raw_event, context):
>>>     from awsmate.sns import LambdaMessageEvent
>>>     event = LambdaMessageEvent(raw_event)

event_subscription_arn() → str

Returns the arn of the subscription that led this message to be sent.

Returns:: The arn of the SNS subscription.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this subscription arn.

Examples

>>> event.event_subscription_arn()
'arn:aws:sns:eu-west-1:123456789012:sns-lambda:aabbccdd-1122-eeff-3344-a1b2c3d4e5f6'

unsubscribe_url() → str

Returns the unsubscription URL of the subscription that led this message to be sent.

Returns:: The unsubscription URL.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this URL.

Examples

>>> event.unsubscribe_url()
'https://sns.eu-west-1.amazonaws.com/?Action=Unsubscribe&amp;SubscriptionArn=arn:aws:sns:eu-west-1:123456789012:your-lambda:aabbccdd-1122-eeff-3344-a1b2c3d4e5f6'

topic_arn() → str

Returns the arn of the topic this message belongs to.

Returns:: The arn of the SNS topic.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this topic arn.

Examples

>>> event.topic_arn()
'arn:aws:sns:eu-west-1:123456789012:sns-lambda'

signature() → str

Returns the signature of the message.

Returns:: The signature of the message.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this signature.

Examples

>>> event.signature()
'On1AdgZdIdWOHBltcSQCLuy+mE/Nozp9QHYGXSHVjhwZbXEkAi7svphPzaM='

signing_cert_url() → str

Returns the URL of the certificate that allows checking the signature of this message.

Returns:: The signature of the message.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this URL.

Examples

>>> event.signing_cert_url()
'https://sns.eu-west-1.amazonaws.com/SimpleNotificationService-aa11bb22cc33dd44ee55ff66ee55dd44.pem'

See also

signature()

message_id() → str

Returns the unique identifier of the message.

Returns:: The id of the message.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this identifier.

Examples

>>> event.message_id()
'a1b2c3d4-e5f6-aa11-bb22-f6e5d4c3b2a4'

subject() → str | None

Returns the subject of the message if any.

Returns:: The subject of the message or None if omitted.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this subject.

Examples

>>> event.message_subject()
'Some subject'

message() → str

Returns the content of the message.

Returns:: The content of the message.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this content.

Examples

>>> event.message()
'some text'

message_type() → str

Returns the type of the message.

This type is returned as transmitted by AWS SNS. No verification is performed.

Returns:: The type of the message.
Return type:: str
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving this type.

Examples

>>> event.message_type()
'Notification'

message_attributes() → dict

Returns the attributes of the message, if any.

Attributes must comply to the AWS SNS attributes specifications. Binary values are decoded from base-64 to binary strings.

Returns:: The attributes of the message, which is empty if no attribute is specified.
Return type:: dict
Raises:: awsmate.lambdafunction.AwsEventSpecificationError – If the event structure does not allow retrieving such attributes or if their do not comply to AWS SNS attributes specifications.

Examples

>>> event.message_attributes()
{'AttributeName': {'Type': 'String', 'Value': 'Some text'}, 'OtherAttributeName': {'Type': 'Binary', 'Value': b'Some decoded binary'}}