Update app.py

app.py

@@ -3,22 +3,38 @@ import random
 import requests
 import os
 from datetime import datetime
+import hashlib
+import hmac
 
+def sign(key, msg):
+    return hmac.new(key, msg.encode('utf-8'), hashlib.sha256).digest()
+
+def get_signature_key(secret_key, date_stamp, region_name, service_name):
+    k_date = sign(('AWS4' + secret_key).encode('utf-8'), date_stamp)
+    k_region = sign(k_date, region_name)
+    k_service = sign(k_region, service_name)
+    k_signing = sign(k_service, 'aws4_request')
+    return k_signing
 
 def generate_response(input, history):
     #bot_message = random.choice(["How are you?", "I love you", "I'm very hungry"])
 
+    #Authentication AWS
+    access_key = os.environ['AccessKey']
+    secret_key = os.environ['SecretKey']
+    region = 'eu-west-1' # e.g., 'us-west-2'
+    service = 'sagemaker'
+    
     #Hit the Sagemaker API and get results
     
     url = "https://runtime.sagemaker.eu-west-1.amazonaws.com/endpoints/jumpstart-dft-meta-textgeneration-llama-2-7b-f/invocations"
-    authorization_token = os.environ['Authorization']
-    headers = {
-        "Content-Type": "application/json",
-        "Authorization": authorization_token,  # Replace with your actual token
-        "X-Amz-Date": datetime.utcnow().strftime("%Y%m%dT%H%M%SZ"),  # Using ISO-8601 basic format
-        "X-Amzn-SageMaker-Custom-Attributes": "accept_eula=true",
-        "Connection": "keep-alive"
-    }
+    #authorization_token = os.environ['Authorization']
+    # headers = {
+    #     "Content-Type": "application/json",
+    #     "X-Amz-Date": datetime.utcnow().strftime("%Y%m%dT%H%M%SZ"),  # Using ISO-8601 basic format
+    #     "X-Amzn-SageMaker-Custom-Attributes": "accept_eula=true",
+    #     "Connection": "keep-alive"
+    # }
     payload = {
         "inputs": [
             [
@@ -39,6 +55,37 @@ def generate_response(input, history):
         }
     }
 
+    payload_str = json.dumps(payload)
+
+    t = datetime.utcnow()
+    amz_date = t.strftime('%Y%m%dT%H%M%SZ')
+    date_stamp = t.strftime('%Y%m%d')
+    
+    canonical_uri = '/data' # Your canonical URI here
+    canonical_headers = f'host:{endpoint}\nx-amz-date:{amz_date}\n'
+    signed_headers = 'host;x-amz-date'
+    
+    hashlib_payload = hashlib.sha256(payload_str.encode('utf-8')).hexdigest()
+    canonical_request = f'POST\n{canonical_uri}\n\n{canonical_headers}\n{signed_headers}\n{hashlib_payload}'
+    
+    algorithm = 'AWS4-HMAC-SHA256'
+    credential_scope = f'{date_stamp}/{region}/{service}/aws4_request'
+    string_to_sign = f'{algorithm}\n{amz_date}\n{credential_scope}\n{hashlib.sha256(canonical_request.encode("utf-8")).hexdigest()}'
+    
+    signing_key = get_signature_key(secret_key, date_stamp, region, service)
+    signature = hmac.new(signing_key, (string_to_sign).encode('utf-8'), hashlib.sha256).hexdigest()
+    
+    authorization_header = f'{algorithm} Credential={access_key}/{credential_scope}, SignedHeaders={signed_headers}, Signature={signature}'
+    
+    headers = {
+        'x-amz-date': amz_date,
+        'Authorization': authorization_header,
+        'Content-Type': 'application/json',
+        "X-Amzn-SageMaker-Custom-Attributes": "accept_eula=true"
+    }
+    
+    #response = requests.post(endpoint, headers=headers, data=payload_str)
+
     
     response = requests.post(url, json=payload, headers=headers)