yamlcalc.py 文件源码

def main():
    """Main application entry point."""
    if len(sys.argv) != 2:
        print "Usage: yamlcalc <input-file>"
        return

    mapping_tag = yaml.resolver.BaseResolver.DEFAULT_MAPPING_TAG
    sequence_tag = yaml.resolver.BaseResolver.DEFAULT_SEQUENCE_TAG

    yaml.add_constructor(mapping_tag, dict_constructor)
    yaml.add_constructor(sequence_tag, list_constructor)
    yaml.add_representer(CalcDict, dict_representer)
    yaml.add_representer(CalcList, list_representer)

    try:
        with open(sys.argv[1]) as infp:
            top = yaml.load(infp)

            if not isinstance(top, CalcDict):
                type_name = type(top).__name__
                err("Top level element should be dict not {0}".format(type_name))

            defs = {}
            defs_str = top.get("DEFS", "")

            try:
                exec defs_str in defs
            except Exception as exc:
                err("Error executing DEFS: {0}".format(exc))

            CalcContainer.set_top(defs, top)

            view = top.get("VIEW", {})
            writer_type = view.get("type", "raw")
            writer_func_name = "_".join(writer_type.split("-"))

            try:
                write = globals()["write_" + writer_func_name]
            except KeyError:
                err("Error unsupporter writer: {0}".format(writer_type))

            outdir, ext = os.path.splitext(sys.argv[1])
            if os.path.exists(outdir):
                if not os.path.isdir(outdir):
                    err("Path exists but is not a directory: {0}".format(outdir))
            else:
                try:
                    os.mkdir(outdir)
                except OSError as exc:
                    err("Error create directory: {0}".format(outdir))

            write(view, top, outdir)
    except IOError as exc:
        err("Error opening file: {0}".format(exc))
    except yaml.YAMLError as exc:
        err("Error parsing input: {0}".format(exc))