import os, traceback class ScriptError(Exception): pass class Script: """ The instantiator should do something along this vein: s = Script(argv, master) s.load() """ def __init__(self, argv, ctx): self.argv = argv self.ctx = ctx self.ns = None def load(self): """ Loads a module. Raises ScriptError on failure, with argument equal to an error message that may be a formatted traceback. """ path = os.path.expanduser(self.argv[0]) if not os.path.exists(path): raise ScriptError("No such file: %s" % path) if not os.path.isfile(path): raise ScriptError("Not a file: %s" % path) ns = {} try: execfile(path, ns, ns) except Exception, v: raise ScriptError(traceback.format_exc(v)) self.ns = ns r = self.run("start", self.argv) if not r[0] and r[1]: raise ScriptError(r[1][1]) def unload(self): return self.run("done") def run(self, name, *args, **kwargs): """ Runs a plugin method. Returns: (True, retval) on success. (False, None) on nonexistent method. (False, (exc, traceback string)) if there was an exception. """ f = self.ns.get(name) if f: try: return (True, f(self.ctx, *args, **kwargs)) except Exception, v: return (False, (v, traceback.format_exc(v))) else: return (False, None)