__all__ = ['require'] import subprocess, os, codecs, glob from .evaljs import translate_js, DEFAULT_HEADER from .translators.friendly_nodes import is_valid_py_name import six DID_INIT = False DIRNAME = os.path.dirname(os.path.abspath(__file__)) PY_NODE_MODULES_PATH = os.path.join(DIRNAME, 'py_node_modules') def _init(): global DID_INIT if DID_INIT: return assert subprocess.call( 'node -v', shell=True, cwd=DIRNAME ) == 0, 'You must have node installed! run: brew install node' assert subprocess.call( 'cd %s;npm install babel-core babel-cli babel-preset-es2015 babel-polyfill babelify browserify browserify-shim' % repr(DIRNAME), shell=True, cwd=DIRNAME) == 0, 'Could not link required node_modules' DID_INIT = True ADD_TO_GLOBALS_FUNC = ''' ;function addToGlobals(name, obj) { if (!Object.prototype.hasOwnProperty('_fake_exports')) { Object.prototype._fake_exports = {}; } Object.prototype._fake_exports[name] = obj; }; ''' # subprocess.call("""node -e 'require("browserify")'""", shell=True) GET_FROM_GLOBALS_FUNC = ''' ;function getFromGlobals(name) { if (!Object.prototype.hasOwnProperty('_fake_exports')) { throw Error("Could not find any value named "+name); } if (Object.prototype._fake_exports.hasOwnProperty(name)) { return Object.prototype._fake_exports[name]; } else { throw Error("Could not find any value named "+name); } }; ''' def _get_module_py_name(module_name): return module_name.replace('-', '_') def _get_module_var_name(module_name): cand = _get_module_py_name(module_name).rpartition('/')[-1] if not is_valid_py_name(cand): raise ValueError( "Invalid Python module name %s (generated from %s). Unsupported/invalid npm module specification?" % ( repr(cand), repr(module_name))) return cand def _get_and_translate_npm_module(module_name, include_polyfill=False, update=False, maybe_version_str=""): assert isinstance(module_name, str), 'module_name must be a string!' py_name = _get_module_py_name(module_name) module_filename = '%s.py' % py_name var_name = _get_module_var_name(module_name) if not os.path.exists(os.path.join(PY_NODE_MODULES_PATH, module_filename)) or update: _init() in_file_name = 'tmp0in439341018923js2py.js' out_file_name = 'tmp0out439341018923js2py.js' code = ADD_TO_GLOBALS_FUNC if include_polyfill: code += "\n;require('babel-polyfill');\n" code += """ var module_temp_love_python = require(%s); addToGlobals(%s, module_temp_love_python); """ % (repr(module_name), repr(module_name)) with open(os.path.join(DIRNAME, in_file_name), 'wb') as f: f.write(code.encode('utf-8') if six.PY3 else code) pkg_name = module_name.partition('/')[0] if maybe_version_str: pkg_name += '@' + maybe_version_str # make sure the module is installed assert subprocess.call( 'cd %s;npm install %s' % (repr(DIRNAME), pkg_name), shell=True, cwd=DIRNAME ) == 0, 'Could not install the required module: ' + pkg_name # convert the module assert subprocess.call( '''node -e "(require('browserify')('./%s').bundle(function (err,data) {if (err) {console.log(err);throw new Error(err);};fs.writeFile('%s', require('babel-core').transform(data, {'presets': require('babel-preset-es2015')}).code, ()=>{});}))"''' % (in_file_name, out_file_name), shell=True, cwd=DIRNAME, ) == 0, 'Error when converting module to the js bundle' os.remove(os.path.join(DIRNAME, in_file_name)) with codecs.open(os.path.join(DIRNAME, out_file_name), "r", "utf-8") as f: js_code = f.read() os.remove(os.path.join(DIRNAME, out_file_name)) if len(js_code) < 50: raise RuntimeError("Candidate JS bundle too short - likely browserify issue.") js_code += GET_FROM_GLOBALS_FUNC js_code += ';var %s = getFromGlobals(%s);%s' % ( var_name, repr(module_name), var_name) print('Please wait, translating...') py_code = translate_js(js_code) dirname = os.path.dirname( os.path.join(PY_NODE_MODULES_PATH, module_filename)) if not os.path.isdir(dirname): os.makedirs(dirname) with open(os.path.join(PY_NODE_MODULES_PATH, module_filename), 'wb') as f: f.write(py_code.encode('utf-8') if six.PY3 else py_code) else: with codecs.open( os.path.join(PY_NODE_MODULES_PATH, module_filename), "r", "utf-8") as f: py_code = f.read() return py_code def require(module_name, include_polyfill=True, update=False, context=None): """ Installs the provided npm module, exports a js bundle via browserify, converts to ECMA 5.1 via babel and finally translates the generated JS bundle to Python via Js2Py. Returns a pure python object that behaves like the installed module. Nice! :param module_name: Name of the npm module to require. For example 'esprima'. Supports specific versions via @ specification. Eg: 'crypto-js@3.3'. :param include_polyfill: Whether the babel-polyfill should be included as part of the translation. May be needed for some modules that use unsupported features of JS6 such as Map or typed arrays. :param update: Whether to force update the translation. Otherwise uses a cached version if exists. :param context: Optional context in which the translated module should be executed in. If provided, the header (js2py imports) will be skipped as it is assumed that the context already has all the necessary imports. :return: The JsObjectWrapper containing the translated module object. Can be used like a standard python object. """ module_name, maybe_version = (module_name+"@@@").split('@')[:2] py_code = _get_and_translate_npm_module(module_name, include_polyfill=include_polyfill, update=update, maybe_version_str=maybe_version) # this is a bit hacky but we need to strip the default header from the generated code... if context is not None: if not py_code.startswith(DEFAULT_HEADER): # new header version? retranslate... assert not update, "Unexpected header." py_code = _get_and_translate_npm_module(module_name, include_polyfill=include_polyfill, update=True) assert py_code.startswith(DEFAULT_HEADER), "Unexpected header." py_code = py_code[len(DEFAULT_HEADER):] context = {} if context is None else context exec(py_code, context) return context['var'][_get_module_var_name(module_name)].to_py()