From ea9dc8d60c648448c42f765fcab265c33cd55c0a Mon Sep 17 00:00:00 2001
From: Steven Armstrong <steven@icarus.ethz.ch>
Date: Fri, 23 Sep 2011 16:43:25 +0200
Subject: [PATCH] handle errors with exceptions instead of function

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
---
 bin/cdist | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/bin/cdist b/bin/cdist
index fe3c17fd..e3d63458 100755
--- a/bin/cdist
+++ b/bin/cdist
@@ -81,9 +81,9 @@ def file_to_list(filename):
 
    return lines
 
-def exit_error(*args):
-   log.error(*args)
-   sys.exit(1)
+class CdistError(Exception):
+    """Base exception class for this project"""
+    pass
 
 class Cdist:
    """Cdist main class to hold arbitrary data"""
@@ -185,9 +185,9 @@ class Cdist:
             print(script_fd.read())
             script_fd.close()
 
-         exit_error("Command failed (shell): " + " ".join(*args))
+         raise CdistError("Command failed (shell): " + " ".join(*args))
       except OSError as error:
-         exit_error(" ".join(*args) + ": " + error.args[1])
+         raise CdistError(" ".join(*args) + ": " + error.args[1])
 
    def run_or_fail(self, *args, **kargs):
       if "remote" in kargs:
@@ -200,9 +200,9 @@ class Cdist:
       try:
          subprocess.check_call(*args, **kargs)
       except subprocess.CalledProcessError:
-         exit_error("Command failed: " + " ".join(*args))
+         raise CdistError("Command failed: " + " ".join(*args))
       except OSError as error:
-         exit_error(" ".join(*args) + ": " + error.args[1])
+         raise CdistError(" ".join(*args) + ": " + error.args[1])
 
 
    def remove_remote_dir(self, destination):
@@ -368,7 +368,7 @@ class Cdist:
       """Run global explorers"""
       explorers = self.list_global_explorers()
       if(len(explorers) == 0):
-         exit_error("No explorers found in", self.global_explorer_dir)
+         raise CdistError("No explorers found in", self.global_explorer_dir)
 
       self.transfer_global_explorers()
       for explorer in explorers:
@@ -674,7 +674,7 @@ def emulator():
       try:
          os.makedirs(param_out_dir, exist_ok=True)
       except OSError as error:
-         exit_error(param_out_dir + ": " + error.args[1])
+         raise CdistError(param_out_dir + ": " + error.args[1])
 
    # Record parameter
    params = vars(args)
@@ -790,3 +790,6 @@ if __name__ == "__main__":
          commandline()
    except KeyboardInterrupt:
        sys.exit(0)
+   except CdistError as e:
+       log.error(e)
+       sys.exit(1)