parse_python3.py

#!/usr/bin/python

import sys
import json as json
import ast

unicode = lambda s: s


def PrintUsage():
    sys.stderr.write("""
Usage:
    parse_python.py <file>

""")
    exit(1)


def read_file_to_string(filename):
    f = open(filename, 'rt')
    s = f.read()
    f.close()
    return s


def parse_file(filename, input="file"):
    global c, d
    if input == "file":
        tree = ast.parse(read_file_to_string(filename), filename)
    else:
        tree = ast.parse(filename)

    json_tree = []

    def gen_identifier(identifier, node_type='identifier'):
        pos = len(json_tree)
        json_node = {}
        json_tree.append(json_node)
        json_node['type'] = node_type
        json_node['value'] = identifier
        return pos

    def traverse_list(l, node_type='list'):
        pos = len(json_tree)
        json_node = {}
        json_tree.append(json_node)
        json_node['type'] = node_type
        children = []
        for item in l:
            children.append(traverse(item))
        if (len(children) != 0):
            json_node['children'] = children
        return pos

    def traverse(node):
        pos = len(json_tree)
        json_node = {}
        json_tree.append(json_node)
        json_node['type'] = type(node).__name__
        children = []
        if isinstance(node, ast.Name):
            json_node['value'] = node.id
        elif isinstance(node, ast.Num):
            json_node['value'] = unicode(node.n)
        elif isinstance(node, ast.Str):
            json_node['value'] = "string"  #node.s #.decode('utf-8')
        elif isinstance(node, ast.alias):
            json_node['value'] = unicode(node.name)
            if node.asname:
                children.append(gen_identifier(node.asname))
        elif isinstance(node, ast.FunctionDef):
            json_node['value'] = unicode(node.name)
        elif isinstance(node, ast.ClassDef):
            json_node['value'] = unicode(node.name)
        elif isinstance(node, ast.ImportFrom):
            if node.module:
                json_node['value'] = unicode(node.module)
        elif isinstance(node, ast.Global):
            for n in node.names:
                children.append(gen_identifier(n))
        elif isinstance(node, ast.keyword):
            json_node['value'] = unicode(node.arg)
        elif isinstance(node, ast.arg):
            children.append(gen_identifier(node.arg))

        # Process children.
        if isinstance(node, ast.For):
            children.append(traverse(node.target))
            children.append(traverse(node.iter))
            children.append(traverse_list(node.body, 'body'))
            if node.orelse:
                children.append(traverse_list(node.orelse, 'orelse'))
        elif isinstance(node, ast.If) or isinstance(node, ast.While):
            children.append(traverse(node.test))
            children.append(traverse_list(node.body, 'body'))
            if node.orelse:
                children.append(traverse_list(node.orelse, 'orelse'))
        elif isinstance(node, ast.With):
            children.append(traverse_list(node.items, 'items'))
            children.append(traverse_list(node.body, 'body'))
        elif isinstance(node, ast.withitem):
            children.append(traverse(node.context_expr))
            if node.optional_vars:
                children.append(traverse(node.optional_vars))
        elif isinstance(node, ast.Try):  # Except
            children.append(traverse_list(node.body, 'body'))
            children.append(traverse_list(node.handlers, 'handlers'))
            if node.orelse:
                children.append(traverse_list(node.orelse, 'orelse'))
            if node.finalbody:
                children.append(traverse_list(node.finalbody, 'finalbody'))
        #elif isinstance(node, ast.TryFinally):
        #    children.append(traverse_list(node.body, 'body'))
        #    children.append(traverse_list(node.finalbody, 'finalbody'))
        elif isinstance(node, ast.arguments):
            children.append(traverse_list(node.args, 'args'))
            children.append(traverse_list(node.defaults, 'defaults'))
            if node.vararg:
                children.append(traverse(node.vararg))
            if node.kwarg:
                children.append(traverse(node.kwarg))
        elif isinstance(node, ast.ExceptHandler):
            if node.type:
                children.append(traverse_list([node.type], 'type'))
            if node.name:
                children.append(gen_identifier(node.name, 'name'))
            children.append(traverse_list(node.body, 'body'))
        elif isinstance(node, ast.ClassDef):
            children.append(traverse_list(node.bases, 'bases'))
            children.append(traverse_list(node.body, 'body'))
            children.append(
                traverse_list(node.decorator_list, 'decorator_list'))
        elif isinstance(node, ast.FunctionDef):
            children.append(traverse(node.args))
            children.append(traverse_list(node.body, 'body'))
            children.append(
                traverse_list(node.decorator_list, 'decorator_list'))
        else:
            # Default handling: iterate over children.
            for child in ast.iter_child_nodes(node):
                if isinstance(child, ast.expr_context) or isinstance(
                        child, ast.operator) or isinstance(
                            child, ast.boolop) or isinstance(
                                child, ast.unaryop) or isinstance(
                                    child, ast.cmpop):
                    # Directly include expr_context, and operators into the type instead of creating a child.
                    json_node['type'] = json_node['type'] + type(
                        child).__name__
                else:
                    children.append(traverse(child))

        if isinstance(node, ast.Attribute):
            children.append(gen_identifier(node.attr, 'attr'))

        if (len(children) != 0):
            json_node['children'] = children
        return pos

    traverse(tree)
    return json.dumps(json_tree, separators=(',', ':'), ensure_ascii=False)


if __name__ == "__main__":
    if len(sys.argv) != 2:
        PrintUsage()
    try:
        print(parse_file(sys.argv[1]))
    except (UnicodeEncodeError, UnicodeDecodeError):
        pass