[Telemetry] Implement automatic installation of optional openCV dependecy.

tools/telemetry/telemetry/core/platform/linux_platform_backend.py

Index: tools/telemetry/telemetry/core/platform/linux_platform_backend.py
diff --git a/tools/telemetry/telemetry/core/platform/linux_platform_backend.py b/tools/telemetry/telemetry/core/platform/linux_platform_backend.py
index 54fde65707b7e81da791bab67dc4d8b1a485da6b..b44a42ee5a9f3a60295e78d72c868cc181ccf17e 100644
--- a/tools/telemetry/telemetry/core/platform/linux_platform_backend.py
+++ b/tools/telemetry/telemetry/core/platform/linux_platform_backend.py
@@ -5,6 +5,7 @@
 import logging
 import os
 import platform
+import site
 import subprocess
 import sys
 
@@ -96,6 +97,10 @@ class LinuxPlatformBackend(
       raise NotImplementedError(
           'Please teach Telemetry how to install ' + application)
 
+  def InstallPythonModule(self, module):
+    if module == 'cv2':
+      self._InstallOpenCV()

[flackr, 2014/10/21 16:08:16]

As with InstallApplication, raise NotImplementedError if we ask for a module we
don't know how to install.

[mthiesse, 2014/10/21 20:01:10]

Done.

+
   def CanMonitorPower(self):
     return self._power_monitor.CanMonitorPower()
 
@@ -154,6 +159,34 @@ class LinuxPlatformBackend(
         'You may proceed by manually building and installing dummynet for ' \
         'your kernel. See: http://info.iet.unipi.it/~luigi/dummynet/'
 
+  def _InstallOpenCV(self):
+    cv2so = support_binaries.FindPath(
+        'cv2.so', self.GetArchName(), self.GetOSName())
+    cloud_storage.GetIfChanged(cv2so, cloud_storage.INTERNAL_BUCKET)
+    if not os.path.exists(cv2so):
+      raise Exception(
+          'Failed to install openCV. You may try installing openCV manually. '
+          'See: github.com/jayrambhia/Install-OpenCV')
+    # These are the openCV dependencies, according to
+    # https://github.com/jayrambhia/Install-OpenCV at the time of writing.
+    # This dependency list may not be exhaustive.
+    print('Installing openCV dependencies:')
+    subprocess.check_call(['sudo', 'apt-get', '-q', 'install',

[tonyg, 2014/10/17 01:15:11]

I wonder whether we should instead add these packages to
build/install-build-deps.sh. That'd make the bots and chromium developers happy.
But the question is on standalone telemetry. Dave, we've talked before about
having it pull third-party deps into the zip. Is that feasible?

[flackr, 2014/10/21 16:08:16]

We could statically link the external lib dependencies for our opencv, if the
resulting library isn't exorbitantly large. The remaining external deps may be
few enough to package and download as well.

Also, do we need the "-dev" versions of all of these packages? If we're fetching
a prebuilt opencv, not building it, don't we just need the libs which are linked
against.

[mthiesse, 2014/10/21 20:01:10]

Yes, it's just difficult to figure out exactly what those are. Is there a way to
figure out which packages are used by a binary?

At any rate, after much experimentation, it seems that the 3 packages
libav-tools libswscale2 python-numpy install everything we need.

+                           'libopencv-dev', 'yasm', 'libjpeg-dev',
+                           'libavcodec-dev', 'libavformat-dev',
+                           'libswscale-dev', 'libdc1394-22-dev',
+                           'libxine-dev', 'libgstreamer0.10-dev',
+                           'libgstreamer-plugins-base0.10-dev', 'libv4l-dev',
+                           'python-dev', 'python-numpy', 'libtbb-dev',
+                           'libqt4-dev', 'libgtk2.0-dev', 'libxvidcore-dev',
+                           'libtheora-dev', 'libx264-dev', 'v4l-utils'])
+    target_dir = site.getsitepackages()[0]
+    target_name = os.path.join(target_dir, 'cv2.so')
+    # First remove any old/incorrect versions.
+    subprocess.check_call(['sudo', 'rm', '-f', target_name])
+    subprocess.check_call(['sudo', 'cp', cv2so, target_dir])
+    subprocess.check_call(['sudo', 'chmod', 'a+r-x', target_name])
+
   def _InstallBinary(self, bin_name, fallback_package=None):
     bin_path = support_binaries.FindPath(
         bin_name, self.GetArchName(), self.GetOSName())