[test] randomize payload

We were using 'x'*size as payload, but on real usage the payload will be
random. This commit randomizes the payload using a predefined seed, so
the random payload will be the same across benchmarks.
Using random payloads also improves accuracy of compression or encoding
impacts and we will be evaluating those changes for resouce usage
issues.
Also note that base64 is used on payload. That was needed for utf8
safety, but overhead was removed to leave payloads as defined by
benchmarks.
Base64 was chosen also due its popular usage on MIME encoding, which is
used on mail attachments (our current scenario).

1 files changed, 12 insertions, 0 deletions

diff --git a/testing/tests/perf/conftest.py b/testing/tests/perf/conftest.py
index 9abd0c54..3681025f 100644
--- a/testing/tests/perf/conftest.py
+++ b/testing/tests/perf/conftest.py
@@ -2,6 +2,8 @@ import json
 import os
 import pytest
 import requests
+import random
+import base64
 import signal
 import time
 
@@ -43,6 +45,16 @@ DEFAULT_CERTKEY = 'soledad_certkey.pem'
 DEFAULT_TOKEN = 'an-auth-token'
 
 
+@pytest.fixture()
+def payload():
+    def generate(size):
+        random.seed(1337)  # same seed to avoid different bench results
+        payload_bytes = bytearray(random.getrandbits(8) for _ in xrange(size))
+        # encode as base64 to avoid ascii encode/decode errors
+        return base64.b64encode(payload_bytes)[:size]  # remove b64 overhead
+    return generate
+
+
 #
 # soledad_dbs fixture: provides all databases needed by soledad server in a per
 # module scope (same databases for all tests in this module).