From 9365848df6e6c92d6e2098e88c2a1b479bec9f4b Mon Sep 17 00:00:00 2001
From: Thomas Leonard <talex5@gmail.com>
Date: Thu, 3 Feb 2005 20:20:37 +0000
Subject: [PATCH] Nicer error reporting if interface is missing.

git-svn-id: file:///home/talex/Backups/sf.net/Subversion/zero-install/injector/head@35 9f8c893c-44ee-0310-b757-c8ca8341c71e
---
 gui.py   | 13 ++++++++++---
 model.py |  2 ++
 run.py   | 12 ++++++++++--
 3 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/gui.py b/gui.py
index 96942ec..dafcb4b 100644
--- a/gui.py
+++ b/gui.py
@@ -3,7 +3,7 @@ from iface_browser import InterfaceBrowser
 import help_box
 from dialog import Dialog
 from policy import policy
-from model import stable, testing, network_levels
+from model import stable, testing, network_levels, SafeException
 
 gtk.rc_parse_string('style "scrolled" { '
 		    'GtkScrolledWindow::scrollbar-spacing = 0}\n'
@@ -84,8 +84,15 @@ class MainWindow(Dialog):
 				self.destroy()
 			elif resp == gtk.RESPONSE_OK:
 				import run
-				run.execute(root_interface, prog, prog_args)
-				self.destroy()
+				try:
+					run.execute(root_interface, prog, prog_args)
+					self.destroy()
+				except SafeException, ex:
+					box = gtk.MessageDialog(self, gtk.DIALOG_MODAL,
+							gtk.MESSAGE_ERROR, gtk.BUTTONS_OK,
+							str(ex))
+					box.run()
+					box.destroy()
 			elif resp == gtk.RESPONSE_HELP:
 				gui_help.display()
 		self.connect('response', response)
diff --git a/model.py b/model.py
index d626ed2..886fdeb 100644
--- a/model.py
+++ b/model.py
@@ -154,3 +154,5 @@ def escape(uri):
 		lambda match: '%%%02x' % ord(match.group(0)),
 		uri.encode('utf-8'))
 
+class SafeException(Exception):
+	pass
diff --git a/run.py b/run.py
index ceffccf..ea9574c 100644
--- a/run.py
+++ b/run.py
@@ -4,7 +4,7 @@ from policy import policy
 from model import *
 
 def do_env_binding(binding, iface):
-	impl = policy.implementation[iface]
+	impl = get_impl(iface)
 	extra = os.path.join(impl.path, binding.insert)
 	if binding.name in os.environ:
 		os.environ[binding.name] = extra + ':' + os.environ[binding.name]
@@ -13,7 +13,7 @@ def do_env_binding(binding, iface):
 
 def execute(iface, prog, prog_args):
 	def setup_bindings(i):
-		impl = policy.implementation[i]
+		impl = get_impl(i)
 		for dep in impl.dependencies.values():
 			dep_iface = dep.get_interface()
 			for b in dep.bindings:
@@ -28,3 +28,11 @@ def execute(iface, prog, prog_args):
 		print "(implementation '%s' + program '%s')" % (policy.implementation[iface].path, prog)
 		sys.exit(1)
 	os.execl(prog_path, prog_path, *prog_args)
+
+def get_impl(interface):
+	try:
+		return policy.implementation[interface]
+	except KeyError:
+		raise SafeException("We don't have enough information to "
+				    "run this program yet. "
+				    "Need to download:\n%s" % interface.uri)
-- 
2.11.4.GIT