Modify devserver and gmerge to be friendlier

devserver.py

Index: devserver.py
diff --git a/devserver.py b/devserver.py
index 7d744c59f3aeb6d44201ccd6d1b777ee152e426d..7de95fa8b423946145cda55a11ad08170f98cc74 100755
--- a/devserver.py
+++ b/devserver.py
@@ -9,6 +9,7 @@
 import cherrypy
 import optparse
 import os
+import subprocess
 import sys
 
 import autoupdate
@@ -69,7 +70,85 @@ def _PrepareToServeUpdatesOnly(image_dir):
                'DEVSERVER')
 
 
-class DevServerRoot:
+def _OutputOf(command):
+  """Runs command, a list of arguments beginning with an executable.
+
+  If the executable begins with "scripts/", the path is adjusted to
+  the scripts directory of this chroot.
+
+  Args:
+    A list of arguments, beginning with the executable
+  Returns:
+    A list of lines returned by the command
+"""
+

[sosa, 2011/01/14 23:03:54]

Don't need this extra line

[rochberg, 2011/01/15 06:16:48]

Done.

+  scripts = 'scripts/'
+  if command[0].find(scripts) == 0:
+    command[0] = command[0].replace(scripts, '../../' + scripts)
+  cherrypy.log('Executing: ' + ' '.join(command), 'BUILD')
+  output_blob = subprocess.Popen(command,
+                                 stdout=subprocess.PIPE).communicate()[0]
+  return [line.rstrip() for line in output_blob.split('\n')]
+

[sosa, 2011/01/14 23:03:54]

2 lines between top level defs

+def _IsIn(needle, haystack_list):

[sosa, 2011/01/14 23:03:54]

Isn't this equivalent to needle in haystick_list?

I just tried with 
a="""tacos are super
delicious taco t
blake"""

"taco" in a = True
"blake" in a = True
"alskdjgasljkg" in a = False

[rochberg, 2011/01/15 06:16:48]

The way the code is structured now, the relevant test would be
"taco" in [a], which is False.  But we don't make any use of the line-oriented
nature of the output, so I'll switch to just plain "in" and the raw output

+  for line in haystack_list:
+    if needle in line:
+      return True
+  return False
+

[sosa, 2011/01/14 23:03:54]

2 lines between top level defs

[rochberg, 2011/01/15 06:16:48]

Done.

+class Builder(object):

[sosa, 2011/01/14 23:03:54]

Should probably move this into its own module.

[rochberg, 2011/01/15 06:16:48]

Done.

+  def _ShouldBeWorkedOn(self, board, pkg):
+    """Is pkg a package that could be worked on, but is not?"""
+    if _IsIn(pkg, _OutputOf([
+        'scripts/cros_workon', '--board=' + board, 'list'])):
+      return False
+
+    # If it's in the list of possible workon targets, we should be working on it
+    return _IsIn(pkg, _OutputOf([
+        'scripts/cros_workon', '--board=' + board, 'list', '--all']))
+
+  def SetError(self, text):
+    cherrypy.response.status = 500
+    cherrypy.log(text, 'BUILD')
+    return text
+
+  def Build(self, board, pkg, additional_args):
+    cherrypy.log('Additional build request arguments: '+ str(additional_args),
+                 'BUILD')
+
+    original_use = os.environ.get('USE', '')
+    if 'use' in additional_args:
+      os.environ['USE'] = original_use + ' ' + additional_args['use']
+      cherrypy.log("USE flags modified to " + os.environ['USE'], 'BUILD')
+
+    try:
+      if (self._ShouldBeWorkedOn(board, pkg) and
+          not additional_args.get('accept_stable')):
+        return self.SetError(
+            'Package is not cros_workon\'d on the devserver machine.\n'
+            'Either start working on the package or pass --accept_stable '
+            'to gmerge')
+
+      rc = subprocess.call(['emerge-%s' % board, pkg])
+      if rc != 0:
+        return self.SetError('Could not emerge ' + pkg)
+
+      cherrypy.log('ecleaning %s' % pkg, 'BUILD')
+      rc = subprocess.call(['eclean-' + board,  '-d', 'packages'])
+      if rc != 0:
+        return self.SetError('eclean failed')
+
+      cherrypy.log('eclean complete %s' % pkg, 'BUILD')
+      return 'Success\n'
+
+    except OSError, e:
+      return self.SetError('Could not execute build command: ' + str(e))
+
+    finally:
+      os.environ['USE'] =  original_use
+
+
+class DevServerRoot(object):
   """The Root Class for the Dev Server.
 
   CherryPy works as follows:
@@ -81,17 +160,12 @@ class DevServerRoot:
     cherrypy uses the update method and puts the extra paths in args.
   """
 
-  def build(self, board, pkg):
+  def __init__(self):
+    self._builder = Builder()
+
+  def build(self, board, pkg, **kwargs):
     """Builds the package specified."""
-    cherrypy.log('emerging %s' % pkg, 'BUILD')
-    emerge_command = 'emerge-%s %s' % (board, pkg)
-    err = os.system(emerge_command)
-    if err != 0:
-      raise Exception('failed to execute %s' % emerge_command)
-    eclean_command = 'eclean-%s -d packages' % board
-    err = os.system(eclean_command)
-    if err != 0:
-      raise Exception('failed to execute %s' % emerge_command)
+    return self._builder.Build(board, pkg, kwargs)
 
   def index(self):
     return 'Welcome to the Dev Server!'