add e2e test to compute hash of pdf and ensure matches

Author: RossFaulds171

tests/e2e-tests/api/letters/test_get_letter_status.py

@@ -1,3 +1,4 @@
+import hashlib
 import requests
 import pytest
 from lib.fixtures import *  # NOSONAR
@@ -22,6 +23,35 @@ def test_200_get_letter_status(url, authentication_secret):
     ErrorHandler.handle_retry(get_message_response)
     assert get_message_response.status_code == 200, f"Response: {get_message_response.status_code}: {get_message_response.text}"
 
+@pytest.mark.test
+@pytest.mark.devtest
+@pytest.mark.inttest
+@pytest.mark.prodtest
+def test_200_get_letter_status_matches_pdf_hash(url, authentication_secret):
+    headers = Generators.generate_valid_headers(authentication_secret)
+
+    ids = get_pending_letter_ids(url, headers, LETTERS_ENDPOINT, limit=1)
+    letter_id = ids[0]
+
+    print(f"calling GET {url}{LETTERS_ENDPOINT}/{letter_id}")
+    get_message_response = requests.get(f"{url}{LETTERS_ENDPOINT}/{letter_id}", headers=headers)
+
+    ErrorHandler.handle_retry(get_message_response)
+    expected_sha256 = get_message_response.json().get("data", {}).get("attributes", {}).get("sha256Hash")
+
+    get_pdf_response = requests.get(
+        f"{url}{LETTERS_ENDPOINT}/{letter_id}/data",
+        headers=headers,
+        allow_redirects=True,
+    )
+    downloaded_pdf_sha256 = hashlib.sha256(get_pdf_response.content).hexdigest()
+
+    assert get_message_response.status_code == 200, f"Response: {get_message_response.status_code}: {get_message_response.text}"
+    assert expected_sha256 is not None, "Expected sha256Hash in GET /letters/{id} response"
+    assert downloaded_pdf_sha256 == expected_sha256, (
+        f"Expected PDF sha256 {expected_sha256}, got {downloaded_pdf_sha256}"
+    )
+
 @pytest.mark.test
 @pytest.mark.devtest
 @pytest.mark.inttest