[ffmpeg] Move version detection to utils

youtube_dl/postprocessor/ffmpeg.py

@@ -11,6 +11,7 @@ from ..utils import (
     compat_subprocess_get_DEVNULL,
     encodeArgument,
     encodeFilename,
+    get_exe_version,
     is_outdated_version,
     PostProcessingError,
     prepend_extension,
@@ -19,23 +20,6 @@ from ..utils import (
 )
 
 
-def get_version(executable):
-    """ Returns the version of the specified executable,
-    or False if the executable is not present """
-    try:
-        out, err = subprocess.Popen(
-            [executable, '-version'],
-            stdout=subprocess.PIPE, stderr=subprocess.STDOUT).communicate()
-    except OSError:
-        return False
-    firstline = out.partition(b'\n')[0].decode('ascii', 'ignore')
-    m = re.search(r'version\s+([0-9._-a-zA-Z]+)', firstline)
-    if not m:
-        return u'present'
-    else:
-        return m.group(1)
-
-
 class FFmpegPostProcessorError(PostProcessingError):
     pass
 
@@ -61,7 +45,7 @@ class FFmpegPostProcessor(PostProcessor):
     @staticmethod
     def get_versions():
         programs = ['avprobe', 'avconv', 'ffmpeg', 'ffprobe']
-        return dict((program, get_version(program)) for program in programs)
+        return dict((p, get_exe_version(p, args=['-version'])) for p in programs)
 
     @property
     def _executable(self):

youtube_dl/utils.py

@@ -1472,6 +1472,25 @@ def check_executable(exe, args=[]):
     return exe
 
 
+def get_exe_version(exe, args=['--version'],
+                    version_re=r'version\s+([0-9._-a-zA-Z]+)',
+                    unrecognized=u'present'):
+    """ Returns the version of the specified executable,
+    or False if the executable is not present """
+    try:
+        out, err = subprocess.Popen(
+            [exe] + args,
+            stdout=subprocess.PIPE, stderr=subprocess.STDOUT).communicate()
+    except OSError:
+        return False
+    firstline = out.partition(b'\n')[0].decode('ascii', 'ignore')
+    m = re.search(version_re, firstline)
+    if m:
+        return m.group(1)
+    else:
+        return unrecognized
+
+
 class PagedList(object):
     def __len__(self):
         # This is only useful for tests