Update Readme for newer library version (#22)

* Update the code sample in Readme

* Update Readme for newer library version

Author: mit-aws

README.md

@@ -21,7 +21,7 @@ sns-extended-client allows for publishing large messages through SNS via S3. Thi
 * use_legacy_attribute -- if `True`, then all published messages use the Legacy reserved message attribute (SQSLargePayloadSize) instead of the current reserved message attribute (ExtendedPayloadSize).
 * message_size_threshold -- the threshold for storing the message in the large messages bucket. Cannot be less than `0` or greater than `262144`. Defaults to `262144`.
 * always_through_s3 -- if `True`, then all messages will be serialized to S3. Defaults to `False`
-* s3 -- the boto3 S3 `resource` object to use to store objects to S3. Use this if you want to control the S3 resource (for example, custom S3 config or credentials). Defaults to `boto3.resource("s3")` on first use if not previously set.
+* s3_client -- the boto3 S3 `client` object to use to store objects to S3. Use this if you want to control the S3 client (for example, custom S3 config or credentials). Defaults to `boto3.client("s3")` on first use if not previously set.
 
 ## Usage
 
@@ -108,25 +108,27 @@ platform_endpoint = resource.PlatformEndpoint('endpoint-arn')
 platform_endpoint.large_payload_support = 'my-bucket-name'
 platform_endpoint.always_through_s3 = True
 ```
-### Setting a custom S3 resource
+### Setting a custom S3 config
 ```python
 import boto3
 from botocore.config import Config
 import sns_extended_client
 
-# Low level client
-sns = boto3.client('sns')
-sns.large_payload_support = 'my-bucket-name'
-sns.s3 = boto3.resource(
-  's3', 
-  config=Config(
-    signature_version='s3v4',
+# Define Configuration for boto3's S3 Client 
+# NOTE - The boto3 version from 1.36.0 to 1.36.6 will throw an error if you enable accelerate_endpoint.
+s3_client_config = Config(
+    region_name = 'us-east-1',
+    signature_version = 's3v4',
     s3={
-      "use_accelerate_endpoint": True
+        "use_accelerate_endpoint":True
     }
-  )
 )
 
+# Low level client
+sns = boto3.client('sns')
+sns.large_payload_support = 'my-bucket-name'
+sns.s3_client = boto3.client("s3", config=s3_client_config)
+
 # boto SNS.Topic resource
 resource = boto3.resource('sns')
 topic = resource.Topic('topic-arn')
@@ -135,30 +137,14 @@ topic = resource.Topic('topic-arn')
 topic = resource.topic(Name='topic-name')
 
 topic.large_payload_support = 'my-bucket-name'
-topic.s3 = boto3.resource(
-  's3', 
-  config=Config(
-    signature_version='s3v4',
-    s3={
-      "use_accelerate_endpoint": True
-    }
-  )
-)
+topic.s3_client = boto3.client("s3", config=s3_client_config)
 
 # boto SNS.PlatformEndpoint resource
 resource = boto3.resource('sns')
 platform_endpoint = resource.PlatformEndpoint('endpoint-arn')
 
 platform_endpoint.large_payload_support = 'my-bucket-name'
-platform_endpoint.s3 = boto3.resource(
-  's3', 
-  config=Config(
-    signature_version='s3v4',
-    s3={
-      "use_accelerate_endpoint": True
-    }
-  )
-)
+platform_endpoint.s3_client = boto3.client("s3", config=s3_client_config)
 ```
 
 ### Setting a custom S3 Key
@@ -230,71 +216,123 @@ s3_extended_payload_bucket = "extended-client-bucket-store"  # S3 bucket with th
 TOPIC_NAME = "---TOPIC-NAME---"
 QUEUE_NAME = "---QUEUE-NAME---"
 
-def get_msg_from_s3(body):
+def allow_sns_to_write_to_sqs(topicarn, queuearn):
+    policy_document = """{{
+        "Version":"2012-10-17",
+        "Statement":[
+            {{
+            "Sid":"MyPolicy",
+            "Effect":"Allow",
+            "Principal" : {{"AWS" : "*"}},
+            "Action":"SQS:SendMessage",
+            "Resource": "{}",
+            "Condition":{{
+                "ArnEquals":{{
+                "aws:SourceArn": "{}"
+                }}
+            }}
+            }}
+        ]
+        }}""".format(queuearn, topicarn)
+
+    return policy_document
+
+def get_msg_from_s3(body,sns_extended_client):
     """Handy Helper to fetch message from S3"""
     json_msg = loads(body)
-    s3_client = boto3.client("s3")
-    s3_object = s3_client.get_object(
+    s3_object = sns_extended_client.s3_client.get_object(
         Bucket=json_msg[1].get("s3BucketName"), Key=json_msg[1].get("s3Key")
     )
     msg = s3_object.get("Body").read().decode()
     return msg
 
 
-def fetch_and_print_from_sqs(sqs, queue_url):
-    message = sqs.receive_message(
-        QueueUrl=queue_url, MessageAttributeNames=["All"], MaxNumberOfMessages=1
+def fetch_and_print_from_sqs(sqs, queue_url,sns_extended_client):
+    sqs_msg = sqs.receive_message(
+        QueueUrl=queue_url,
+        AttributeNames=['All'],
+        MessageAttributeNames=['All'],
+        VisibilityTimeout=0,
+        WaitTimeSeconds=0,
+        MaxNumberOfMessages=1
     ).get("Messages")[0]
-    message_body = message.get("Body")
+    
+    message_body = sqs_msg.get("Body")
     print("Published Message: {}".format(message_body))
-    print("Message Stored in S3 Bucket is: {}\n".format(get_msg_from_s3(message_body)))
+    print("Message Stored in S3 Bucket is: {}\n".format(get_msg_from_s3(message_body,sns_extended_client)))
+
+    # Delete the Processed Message
+    sqs.delete_message(
+        QueueUrl=queue_url,
+        ReceiptHandle=sqs_msg['ReceiptHandle']
+    )
 
 
 sns_extended_client = boto3.client("sns", region_name="us-east-1")
 create_topic_response = sns_extended_client.create_topic(Name=TOPIC_NAME)
-demo_topic_arn = create_topic_response.get("TopicArn")
+sns_topic_arn = create_topic_response.get("TopicArn")
 
 # create and subscribe an sqs queue to the sns client
-sqs = boto3.client("sqs")
+sqs = boto3.client("sqs",region_name="us-east-1")
 demo_queue_url = sqs.create_queue(QueueName=QUEUE_NAME).get("QueueUrl")
-demo_queue_arn = sqs.get_queue_attributes(
+sqs_queue_arn = sqs.get_queue_attributes(
     QueueUrl=demo_queue_url, AttributeNames=["QueueArn"]
 )["Attributes"].get("QueueArn")
 
+# Adding policy to SQS queue such that SNS topic can send msg to SQS queue
+policy_json = allow_sns_to_write_to_sqs(sns_topic_arn, sqs_queue_arn)
+response = sqs.set_queue_attributes(
+    QueueUrl = demo_queue_url,
+    Attributes = {
+        'Policy' : policy_json
+    }
+)
+
 # Set the RawMessageDelivery subscription attribute to TRUE if you want to use
 # SQSExtendedClient to help with retrieving msg from S3
-sns_extended_client.subscribe(TopicArn=demo_topic_arn, Protocol="sqs", 
-Endpoint=demo_queue_arn, Attributes={"RawMessageDelivery":"true"})
+sns_extended_client.subscribe(TopicArn=sns_topic_arn, Protocol="sqs", 
+Endpoint=sqs_queue_arn
+, Attributes={"RawMessageDelivery":"true"}
+)
 
-# Below is the example that all the messages will be sent to the S3 bucket
 sns_extended_client.large_payload_support = s3_extended_payload_bucket
+
+# Change default s3_client attribute of sns_extended_client to use 'us-east-1' region
+sns_extended_client.s3_client = boto3.client("s3", region_name="us-east-1")
+
+
+# Below is the example that all the messages will be sent to the S3 bucket
 sns_extended_client.always_through_s3 = True
 sns_extended_client.publish(
-    TopicArn=demo_topic_arn, Message="This message should be published to S3"
+    TopicArn=sns_topic_arn, Message="This message should be published to S3"
 )
 print("\n\nPublished using SNS extended client:")
-fetch_and_print_from_sqs(sqs, demo_queue_url)  # Prints message stored in s3
+fetch_and_print_from_sqs(sqs, demo_queue_url,sns_extended_client)  # Prints message stored in s3
 
 # Below is the example that all the messages larger than 32 bytes will be sent to the S3 bucket
 print("\nUsing decreased message size threshold:")
 
 sns_extended_client.always_through_s3 = False
 sns_extended_client.message_size_threshold = 32
 sns_extended_client.publish(
-    TopicArn=demo_topic_arn,
+    TopicArn=sns_topic_arn,
     Message="This message should be published to S3 as it exceeds the limit of the 32 bytes",
 )
 
-fetch_and_print_from_sqs(sqs, demo_queue_url)  # Prints message stored in s3
+fetch_and_print_from_sqs(sqs, demo_queue_url,sns_extended_client)  # Prints message stored in s3
 
 
 # Below is the example to publish message using the SNS.Topic resource
 sns_extended_client_resource = SNSExtendedClientSession().resource(
     "sns", region_name="us-east-1"
 )
 
-topic = sns_extended_client_resource.Topic(demo_topic_arn)
+topic = sns_extended_client_resource.Topic(sns_topic_arn)
 topic.large_payload_support = s3_extended_payload_bucket
+
+# Change default s3_client attribute of topic to use 'us-east-1' region
+topic.s3_client = boto3.client("s3", region_name="us-east-1")
+
 topic.always_through_s3 = True
 # Can Set custom S3 Keys to be used to store objects in S3
 topic.publish(
@@ -307,24 +345,51 @@ topic.publish(
     },
 )
 print("\nPublished using Topic Resource:")
-fetch_and_print_from_sqs(sqs, demo_queue_url)
+fetch_and_print_from_sqs(sqs, demo_queue_url,topic)
+
+# Below is the example to publish message using the SNS.PlatformEndpoint resource
+sns_extended_client_resource = SNSExtendedClientSession().resource(
+    "sns", region_name="us-east-1"
+)
+
+platform_endpoint = sns_extended_client_resource.PlatformEndpoint(sns_topic_arn)
+platform_endpoint.large_payload_support = s3_extended_payload_bucket
+
+# Change default s3_client attribute of platform_endpoint to use 'us-east-1' region
+platform_endpoint.s3_client = boto3.client("s3", region_name="us-east-1")
+
+platform_endpoint.always_through_s3 = True
+# Can Set custom S3 Keys to be used to store objects in S3
+platform_endpoint.publish(
+    Message="This message should be published to S3 using the PlatformEndpoint resource",
+    MessageAttributes={
+        "S3Key": {
+            "DataType": "String",
+            "StringValue": "247c11c4-a22c-42e4-a6a2-9b5af5b76587",
+        }
+    },
+)
+print("\nPublished using PlatformEndpoint Resource:")
+fetch_and_print_from_sqs(sqs, demo_queue_url,platform_endpoint)
 ```
 
 PRODUCED OUTPUT:
 ```
 Published using SNS extended client:
-Published Message: ["software.amazon.payloadoffloading.PayloadS3Pointer", {"s3BucketName": "extended-client-bucket-store", "s3Key": "465d51ea-2c85-4cf8-9ff7-f0a20636ac54"}]
+Published Message: ["software.amazon.payloadoffloading.PayloadS3Pointer", {"s3BucketName": "extended-client-bucket-store", "s3Key": "10999f58-c5ae-4d68-9208-f70475e0113d"}]
 Message Stored in S3 Bucket is: This message should be published to S3
 
-
 Using decreased message size threshold:
-Published Message: ["software.amazon.payloadoffloading.PayloadS3Pointer", {"s3BucketName": "extended-client-bucket-store", "s3Key": "4e32bc6c-e67e-4e09-982b-66dfbe0c588a"}]
+Published Message: ["software.amazon.payloadoffloading.PayloadS3Pointer", {"s3BucketName": "extended-client-bucket-store", "s3Key": "2c5cb2c7-e649-492b-85fb-fa9923cb02bf"}]
 Message Stored in S3 Bucket is: This message should be published to S3 as it exceeds the limit of the 32 bytes
 
-
 Published using Topic Resource:
 Published Message: ["software.amazon.payloadoffloading.PayloadS3Pointer", {"s3BucketName": "extended-client-bucket-store", "s3Key": "347c11c4-a22c-42e4-a6a2-9b5af5b76587"}]
 Message Stored in S3 Bucket is: This message should be published to S3 using the topic resource
+
+Published using PlatformEndpoint Resource:
+Published Message: ["software.amazon.payloadoffloading.PayloadS3Pointer", {"s3BucketName": "extended-client-bucket-store", "s3Key": "247c11c4-a22c-42e4-a6a2-9b5af5b76587"}]
+Message Stored in S3 Bucket is: This message should be published to S3 using the PlatformEndpoint resource
 ```
 
 ## DEVELOPMENT
@@ -342,5 +407,4 @@ See [CONTRIBUTING](CONTRIBUTING.md#security-issue-notifications) for more inform
 
 ## License
 
-This project is licensed under the Apache-2.0 License.
-
+This project is licensed under the Apache-2.0 License.