launchpad-reviewers team mailing list archive

[Colin Watson <cjwatson@xxxxxxxxxxxxx>]

Colin Watson has proposed merging ~cjwatson/launchpad:gi-is-optional into launchpad:master.

Commit message:
Make the system "gi" package optional

Requested reviews:
  Launchpad code reviewers (launchpad-reviewers)

For more details, see:
https://code.launchpad.net/~cjwatson/launchpad/+git/launchpad/+merge/382990

The gi (gobject-introspection) package is only used in the test suite, and isn't installed by launchpad-dependencies.  Make it optional.
-- 
Your team Launchpad code reviewers is requested to review the proposed merge of ~cjwatson/launchpad:gi-is-optional into launchpad:master.

diff --git a/system-packages.txt b/system-packages.txt
index 1737888..5fe7918 100644
--- a/system-packages.txt
+++ b/system-packages.txt
@@ -3,6 +3,10 @@
 # Python dependency is impossible or unreliable (perhaps due to frequent ABI
 # changes in system libraries they depend on, or frequent security updates
 # managed by the distribution's security team).
+#
+# Package names that end with "?" are optional, in that link-system-packages
+# will not fail if they are missing; this should be reserved for packages
+# only used by the test suite.
 
 # Used by launchpad-buildd.
 apt
@@ -19,7 +23,7 @@ convoy
 GeoIP
 
 # lp.testing.html5browser
-gi
+gi?
 
 # lp.services.fields, lp.services.spriteutils
 PIL
@@ -28,5 +32,5 @@ PIL
 sqlite
 _sqlite
 
-# Optional dependency of bzr-git and bzr-svn.
+# Used by bzr-git and bzr-svn.
 tdb
diff --git a/utilities/link-system-packages.py b/utilities/link-system-packages.py
index 07d0f9b..18b863b 100755
--- a/utilities/link-system-packages.py
+++ b/utilities/link-system-packages.py
@@ -14,8 +14,15 @@ import os.path
 import re
 
 
-def link_module(name, virtualenv_libdir):
-    module = importlib.import_module(name)
+def link_module(name, virtualenv_libdir, optional=False):
+    try:
+        module = importlib.import_module(name)
+    except ImportError:
+        if optional:
+            print("Skipping missing optional module %s." % name)
+            return
+        else:
+            raise
     path = module.__file__
     if os.path.basename(path).startswith("__init__."):
         path = os.path.dirname(path)
@@ -40,7 +47,12 @@ def main():
         line = re.sub(r"#.*", "", line).strip()
         if not line:
             continue
-        link_module(line, args.virtualenv_libdir)
+        if line.endswith("?"):
+            line = line[:-1]
+            optional = True
+        else:
+            optional = False
+        link_module(line, args.virtualenv_libdir, optional=optional)
 
 
 if __name__ == "__main__":