added skip check for playback server

tests/test_data.py

@@ -14,6 +14,7 @@
 from pathlib import Path
 import os.path
 from itertools import product
+import subprocess
 
 
 def generate_audio_data(samplerate, channels, dtype):
@@ -125,13 +126,23 @@ def test_get_timestamp(self):
         ts = get_timestamp()
         self.assertIsInstance(ts, int)
 
-    def test_camera_file_snapshot(self):
+
+def playback_server_available():
+    try:
+        output = subprocess.check_output(["docker-compose", "logs", "playback-server"])
+    except subprocess.CalledProcessError:
+        return False
+    return b"Serving data" in output
+
+
+class TestCamera(unittest.TestCase):
+    def test_file_snapshot(self):
         # open test.mp4 is a test video 90 480x640 frames
         cam = Camera("file://tests/test.mp4")
         sample = cam.snapshot()
         assert sample.data.shape == (640, 480, 3)
 
-    def test_camera_file_stream(self):
+    def test_file_stream(self):
         # open test.mp4 is a test video 90 480x640 frames
         cam = Camera("file://tests/test.mp4")
         numframes = 0
@@ -140,13 +151,15 @@ def test_camera_file_stream(self):
             numframes += 1
         assert numframes == 90
 
-    def test_camera_stream_snapshot(self):
+    @unittest.skipUnless(playback_server_available(), "playback server not available")
+    def test_stream_snapshot(self):
         # open playback server which provides test video stream of 800x600 frames
         cam = Camera("http://127.0.0.1:8090/bottom/live.mp4")
         sample = cam.snapshot()
         assert sample.data.shape == (600, 800, 3)
 
-    def test_camera_stream_stream(self):
+    @unittest.skipUnless(playback_server_available(), "playback server not available")
+    def test_stream_stream(self):
         # open playback server which provides test video stream of 800x600 frames
         cam = Camera("http://127.0.0.1:8090/bottom/live.mp4")
         numframes = 0