From e38914be0eb0da5a34ea45bbc2c630215f551c22 Mon Sep 17 00:00:00 2001
From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sat, 6 Aug 2011 20:20:47 +0200
Subject: [PATCH] Add "check-update" command.

Does the same as "update" does, but breaks after calculating the
transaction.
---
 pakfire/api.py  |  4 ++--
 pakfire/base.py | 17 ++++++++++++++++-
 pakfire/cli.py  | 13 +++++++++++++
 3 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/pakfire/api.py b/pakfire/api.py
index 983c4506d..f6b16568b 100644
--- a/pakfire/api.py
+++ b/pakfire/api.py
@@ -40,10 +40,10 @@ def remove(what, **pakfire_args):
 
 	return pakfire.remove(what)
 
-def update(pkgs, **pakfire_args):
+def update(pkgs, check=False, **pakfire_args):
 	pakfire = Pakfire(**pakfire_args)
 
-	return pakfire.update(pkgs)
+	return pakfire.update(pkgs, check=check)
 
 def info(patterns, **pakfire_args):
 	# Create pakfire instance.
diff --git a/pakfire/base.py b/pakfire/base.py
index 545a382ec..994cc2425 100644
--- a/pakfire/base.py
+++ b/pakfire/base.py
@@ -239,7 +239,11 @@ class Pakfire(object):
 			# Remove the temporary copy of the repository we have created earlier.
 			repo.remove()
 
-	def update(self, pkgs):
+	def update(self, pkgs, check=False):
+		"""
+			check indicates, if the method should return after calculation
+			of the transaction.
+		"""
 		request = self.create_request()
 
 		# If there are given any packets on the command line, we will
@@ -257,6 +261,17 @@ class Pakfire(object):
 
 		if not t:
 			logging.info(_("Nothing to do"))
+
+			# If we are running in check mode, we return a non-zero value to
+			# indicate, that there are no updates.
+			if check:
+				return 1
+			else:
+				return
+
+		# Just exit here, because we won't do the transaction in this mode.
+		if check:
+			t.dump()
 			return
 
 		# Ask the user if the transaction is okay.
diff --git a/pakfire/cli.py b/pakfire/cli.py
index 1d4de7ced..35ddaea7d 100644
--- a/pakfire/cli.py
+++ b/pakfire/cli.py
@@ -56,6 +56,7 @@ class Cli(object):
 		self.parse_command_remove()
 		self.parse_command_info()
 		self.parse_command_search()
+		self.parse_command_check_update()
 		self.parse_command_update()
 		self.parse_command_provides()
 		self.parse_command_grouplist()
@@ -71,6 +72,7 @@ class Cli(object):
 			"install"      : self.handle_install,
 			"localinstall" : self.handle_localinstall,
 			"remove"       : self.handle_remove,
+			"check_update" : self.handle_check_update,
 			"update"       : self.handle_update,
 			"info"         : self.handle_info,
 			"search"       : self.handle_search,
@@ -148,6 +150,14 @@ class Cli(object):
 			help=_("Give a name of a package to update or leave emtpy for all."))
 		sub_update.add_argument("action", action="store_const", const="update")
 
+	def parse_command_check_update(self):
+		# Implement the "check-update" command.
+		sub_check_update = self.sub_commands.add_parser("check-update",
+			help=_("Check, if there are any updates available."))
+		sub_check_update.add_argument("package", nargs="*",
+			help=_("Give a name of a package to update or leave emtpy for all."))
+		sub_check_update.add_argument("action", action="store_const", const="check_update")
+
 	def parse_command_info(self):
 		# Implement the "info" command.
 		sub_info = self.sub_commands.add_parser("info",
@@ -240,6 +250,9 @@ class Cli(object):
 	def handle_update(self):
 		pakfire.update(self.args.package, **self.pakfire_args)
 
+	def handle_check_update(self):
+		pakfire.update(self.args.package, check=True, **self.pakfire_args)
+
 	def handle_install(self):
 		pakfire.install(self.args.package, **self.pakfire_args)
 
-- 
2.39.5