Add support dumping and loading from JSON/YAML in gaudirun.py

this MR adds the possibility of dumping a configuration as .json and .yaml via the gaudirun.py --output option (same as with .opts, .pkl and .py formats).

The generated JSON/YAML files can then be used as input to the configuration, same as .opts or .pkl files (.py dumps cannot be used to configure the application).

The support for .yaml (or .yml) dumps is available only if the Python package PyYAML is available.

Closes #200 (closed)

Gaudi/python/Gaudi/Main.py

@@ -221,7 +221,7 @@ def _getAllOpts_old(explicit_defaults=False):
 
 def getAllOpts(explicit_defaults=False):
     """
-    Return all options from the old and configuration system as a dictionary.
+    Return all options from the old and new configuration system as a dictionary.
 
     If explicit_defaults is true, include default values of unset properties in the dictionary.
     """
@@ -405,17 +405,26 @@ class gaudimain(object):
         sys.stdout.flush()
 
     def writeconfig(self, filename, all=False):
+        import json
         write = {".pkl": lambda filename, all: self._writepickle(filename),
                  ".py": lambda filename, all: open(filename, "w").write(self.generatePyOutput(all) + "\n"),
                  ".opts": lambda filename, all: open(filename, "w").write(self.generateOptsOutput(all) + "\n"),
+                 ".json": lambda filename, all: json.dump(getAllOpts(all), open(filename, "w"), indent=2, sort_keys=True),
                  }
+        try:
+            import yaml
+            write[".yaml"] = lambda filename, all: yaml.safe_dump(getAllOpts(all), open(filename, "w"))
+            write[".yml"] = write[".yaml"]
+        except ImportError:
+            pass  # yaml support is optional
+
         from os.path import splitext
         ext = splitext(filename)[1]
         if ext in write:
             write[ext](filename, all)
         else:
             log.error("Unknown file type '%s'. Must be any of %r.", ext,
-                      write.keys())
+                      sorted(write.keys()))
             sys.exit(1)
 
     # Instantiate and run the application.