From b10cfa841a0ad6006c0fa362097725d3fef5b70e Mon Sep 17 00:00:00 2001
From: Gregory Haynes <greg@greghaynes.net>
Date: Wed, 19 Nov 2014 03:59:49 -0800
Subject: [PATCH] Make some pkg-map errors soft

An app using pkg-map (like package-installs) might want to distinguish
between a hard error (invalid pkg-map file) and a soft error (no
mapping found). Currently this is not possible because we only return
with error values of 1.

Also printing error messages to stderror so we can still make use of
stdout data during a soft error.

Change-Id: I8bef56d3a74e8530afb8c58ac50ca3e9f7700639
---
 elements/pkg-map/bin/pkg-map | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/elements/pkg-map/bin/pkg-map b/elements/pkg-map/bin/pkg-map
index 0ff696ad..8f3fc128 100755
--- a/elements/pkg-map/bin/pkg-map
+++ b/elements/pkg-map/bin/pkg-map
@@ -20,6 +20,11 @@ import os
 import sys
 
 
+def eprint(msg):
+    sys.stderr.write(msg)
+    sys.stderr.write("\n")
+
+
 def os_family(distro):
     family = None
     if distro in ['fedora', 'rhel', 'rhel7', 'centos7']:
@@ -34,26 +39,32 @@ def os_family(distro):
 
 def main():
     parser = argparse.ArgumentParser(
-        description="Translate package name to distro specific name.")
+        description="Translate package name to distro specific name."
+                    " Exits with 1 if error is encountered, 2 if no pkg-map"
+                    " file is found. Otherwise exits with 0.")
     parser.add_argument('--element', default='',
                         help='The element (namespace) to use for translation.')
     parser.add_argument('--distro', default=os.environ.get('DISTRO_NAME'),
                         help='The distro name to use for translation.'
                         ' Defaults to DISTRO_NAME')
+    parser.add_argument('--missing-ok', action="store_true",
+                        help='Do not consider missing mappings an error.'
+                             ' Causes packages where no mapping is set to be'
+                             ' printed.')
     args, extra = parser.parse_known_args()
 
     if not args.element:
-        print('Please specify an --element argument.')
+        eprint('Please specify an --element argument.')
         sys.exit(1)
 
     if not args.distro:
-        print('Please specify a --distro argument or set DISTRO_NAME.')
+        eprint('Please specify a --distro argument or set DISTRO_NAME.')
         sys.exit(1)
 
     map_file = '/usr/share/pkg-map/%s' % args.element
     if not os.path.exists(map_file):
-        print('Map file for %s element does not exist.' % args.element)
-        sys.exit(1)
+        eprint('Map file for %s element does not exist.' % args.element)
+        sys.exit(2)
 
     with open(map_file) as fd:
         package_names = json.loads(fd.read())
@@ -93,6 +104,7 @@ def main():
         distro_map = package_names['distro'].get(args.distro)
         if distro_map:
             name_map.update(distro_map)
+
     for name in extra:
         pkg_name = name_map.get(name)
         if pkg_name:
@@ -101,8 +113,11 @@ def main():
             continue
         else:
             err_msg = 'Missing package name for distro/element: %s/%s'
-            print(err_msg % (args.distro, args.element))
-            sys.exit(1)
+            eprint(err_msg % (args.distro, args.element))
+            if args.missing_ok:
+                print(name)
+            else:
+                sys.exit(1)
 
     sys.exit(0)