Merge pull request #276 from rmarren1/ide

IDE support

Author: rmarren1

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.23.0 - 2018-08-01
+## Added
+- Dash components are now generated at build-time and then imported rather than generated when a module is imported. This should reduce the time it takes to import Dash component libraries, and makes Dash compatible with IDEs.
+
 ## 0.22.1 - 2018-08-01
 ## Fixed
 - Raise a more informative error if a non JSON serializable value is returned from a callback [#273](https://github.com/plotly/dash/pull/273)
@@ -7,6 +11,7 @@
 - Assets files & index customization [#286](https://github.com/plotly/dash/pull/286)
 - Raise an error if there is no layout present when the server is running [#294](https://github.com/plotly/dash/pull/294)
 
+
 ## 0.21.1 - 2018-04-10
 ## Added
 - `aria-*` and `data-*` attributes are now supported in all dash html components. (#40)

dash/development/base_component.py

@@ -1,5 +1,7 @@
 import collections
 import copy
+import os
+import inspect
 
 
 def is_number(s):
@@ -18,7 +20,56 @@ def _check_if_has_indexable_children(item):
         raise KeyError
 
 
+def _explicitize_args(func):
+    # Python 2
+    if hasattr(func, 'func_code'):
+        varnames = func.func_code.co_varnames
+    # Python 3
+    else:
+        varnames = func.__code__.co_varnames
+
+    def wrapper(*args, **kwargs):
+        if '_explicit_args' in kwargs.keys():
+            raise Exception('Variable _explicit_args should not be set.')
+        kwargs['_explicit_args'] = \
+            list(
+                set(
+                    list(varnames[:len(args)]) + [k for k, _ in kwargs.items()]
+                )
+            )
+        if 'self' in kwargs['_explicit_args']:
+            kwargs['_explicit_args'].remove('self')
+        return func(*args, **kwargs)
+
+    # If Python 3, we can set the function signature to be correct
+    if hasattr(inspect, 'signature'):
+        # pylint: disable=no-member
+        new_sig = inspect.signature(wrapper).replace(
+            parameters=inspect.signature(func).parameters.values()
+        )
+        wrapper.__signature__ = new_sig
+    return wrapper
+
+
 class Component(collections.MutableMapping):
+    class _UNDEFINED(object):
+        def __repr__(self):
+            return 'undefined'
+
+        def __str__(self):
+            return 'undefined'
+
+    UNDEFINED = _UNDEFINED()
+
+    class _REQUIRED(object):
+        def __repr__(self):
+            return 'required'
+
+        def __str__(self):
+            return 'required'
+
+    REQUIRED = _REQUIRED()
+
     def __init__(self, **kwargs):
         # pylint: disable=super-init-not-called
         for k, v in list(kwargs.items()):
@@ -214,9 +265,9 @@ def __len__(self):
 
 
 # pylint: disable=unused-argument
-def generate_class(typename, props, description, namespace):
+def generate_class_string(typename, props, description, namespace):
     """
-    Dynamically generate classes to have nicely formatted docstrings,
+    Dynamically generate class strings to have nicely formatted docstrings,
     keyword arguments, and repr
 
     Inspired by http://jameso.be/2013/08/06/namedtuple.html
@@ -230,6 +281,7 @@ def generate_class(typename, props, description, namespace):
 
     Returns
     -------
+    string
 
     """
     # TODO _prop_names, _type, _namespace, available_events,
@@ -250,7 +302,8 @@ def generate_class(typename, props, description, namespace):
     # not all component authors will supply those.
     c = '''class {typename}(Component):
     """{docstring}"""
-    def __init__(self, {default_argtext}):
+    @_explicitize_args
+    def __init__(self, {default_argtext}, **kwargs):
         self._prop_names = {list_of_valid_keys}
         self._type = '{typename}'
         self._namespace = '{namespace}'
@@ -261,11 +314,15 @@ def __init__(self, {default_argtext}):
         self.available_wildcard_properties =\
             {list_of_valid_wildcard_attr_prefixes}
 
+        _explicit_args = kwargs.pop('_explicit_args')
+        _locals = locals()
+        _locals.update(kwargs)  # For wildcard attrs
+        args = {{k: _locals[k] for k in _explicit_args if k != 'children'}}
+
         for k in {required_args}:
-            if k not in kwargs:
+            if k not in args:
                 raise TypeError(
                     'Required argument `' + k + '` was not specified.')
-
         super({typename}, self).__init__({argtext})
 
     def __repr__(self):
@@ -290,13 +347,13 @@ def __repr__(self):
             return (
                 '{typename}(' +
                 repr(getattr(self, self._prop_names[0], None)) + ')')
-    '''
+'''
 
     filtered_props = reorder_props(filter_props(props))
     # pylint: disable=unused-variable
     list_of_valid_wildcard_attr_prefixes = repr(parse_wildcards(props))
     # pylint: disable=unused-variable
-    list_of_valid_keys = repr(list(filtered_props.keys()))
+    list_of_valid_keys = repr(list(map(str, filtered_props.keys())))
     # pylint: disable=unused-variable
     docstring = create_docstring(
         component_name=typename,
@@ -306,19 +363,82 @@ def __repr__(self):
 
     # pylint: disable=unused-variable
     events = '[' + ', '.join(parse_events(props)) + ']'
+    prop_keys = list(props.keys())
     if 'children' in props:
-        default_argtext = 'children=None, **kwargs'
+        prop_keys.remove('children')
+        default_argtext = "children=None, "
         # pylint: disable=unused-variable
-        argtext = 'children=children, **kwargs'
+        argtext = 'children=children, **args'
     else:
-        default_argtext = '**kwargs'
-        argtext = '**kwargs'
+        default_argtext = ""
+        argtext = '**args'
+    default_argtext += ", ".join(
+        [('{:s}=Component.REQUIRED'.format(p)
+          if props[p]['required'] else
+          '{:s}=Component.UNDEFINED'.format(p))
+         for p in prop_keys
+         if not p.endswith("-*") and
+         p not in ['dashEvents', 'fireEvent', 'setProps']]
+    )
 
     required_args = required_props(props)
+    return c.format(**locals())
+
+
+# pylint: disable=unused-argument
+def generate_class_file(typename, props, description, namespace):
+    """
+    Generate a python class file (.py) given a class string
 
-    scope = {'Component': Component}
+    Parameters
+    ----------
+    typename
+    props
+    description
+    namespace
+
+    Returns
+    -------
+
+    """
+    import_string =\
+        "# AUTO GENERATED FILE - DO NOT EDIT\n\n" + \
+        "from dash.development.base_component import " + \
+        "Component, _explicitize_args\n\n\n"
+    class_string = generate_class_string(
+        typename,
+        props,
+        description,
+        namespace
+    )
+    file_name = "{:s}.py".format(typename)
+
+    file_path = os.path.join(namespace, file_name)
+    with open(file_path, 'w') as f:
+        f.write(import_string)
+        f.write(class_string)
+
+
+# pylint: disable=unused-argument
+def generate_class(typename, props, description, namespace):
+    """
+    Generate a python class object given a class string
+
+    Parameters
+    ----------
+    typename
+    props
+    description
+    namespace
+
+    Returns
+    -------
+
+    """
+    string = generate_class_string(typename, props, description, namespace)
+    scope = {'Component': Component, '_explicitize_args': _explicitize_args}
     # pylint: disable=exec-used
-    exec(c.format(**locals()), scope)
+    exec(string, scope)
     result = scope[typename]
     return result
 

dash/development/component_loader.py

@@ -1,6 +1,18 @@
 import collections
 import json
+import os
 from .base_component import generate_class
+from .base_component import generate_class_file
+
+
+def _get_metadata(metadata_path):
+    # Start processing
+    with open(metadata_path) as data_file:
+        json_string = data_file.read()
+        data = json\
+            .JSONDecoder(object_pairs_hook=collections.OrderedDict)\
+            .decode(json_string)
+    return data
 
 
 def load_components(metadata_path,
@@ -20,12 +32,7 @@ def load_components(metadata_path,
 
     components = []
 
-    # Start processing
-    with open(metadata_path) as data_file:
-        json_string = data_file.read()
-        data = json\
-            .JSONDecoder(object_pairs_hook=collections.OrderedDict)\
-            .decode(json_string)
+    data = _get_metadata(metadata_path)
 
     # Iterate over each property name (which is a path to the component)
     for componentPath in data:
@@ -47,3 +54,56 @@ def load_components(metadata_path,
         components.append(component)
 
     return components
+
+
+def generate_classes(namespace, metadata_path='lib/metadata.json'):
+    """Load React component metadata into a format Dash can parse,
+    then create python class files.
+
+    Usage: generate_classes()
+
+    Keyword arguments:
+    namespace -- name of the generated python package (also output dir)
+
+    metadata_path -- a path to a JSON file created by
+    [`react-docgen`](https://github.com/reactjs/react-docgen).
+
+    Returns:
+    """
+
+    data = _get_metadata(metadata_path)
+    imports_path = os.path.join(namespace, '_imports_.py')
+
+    # Make sure the file doesn't exist, as we use append write
+    if os.path.exists(imports_path):
+        os.remove(imports_path)
+
+    # Iterate over each property name (which is a path to the component)
+    for componentPath in data:
+        componentData = data[componentPath]
+
+        # Extract component name from path
+        # e.g. src/components/MyControl.react.js
+        # TODO Make more robust - some folks will write .jsx and others
+        # will be on windows. Unfortunately react-docgen doesn't include
+        # the name of the component atm.
+        name = componentPath.split('/').pop().split('.')[0]
+        generate_class_file(
+            name,
+            componentData['props'],
+            componentData['description'],
+            namespace
+        )
+
+        # Add an import statement for this component
+        with open(imports_path, 'a') as f:
+            f.write('from .{0:s} import {0:s}\n'.format(name))
+
+    # Add the __all__ value so we can import * from _imports_
+    all_imports = [p.split('/').pop().split('.')[0] for p in data]
+    with open(imports_path, 'a') as f:
+        array_string = '[\n'
+        for a in all_imports:
+            array_string += '    "{:s}",\n'.format(a)
+        array_string += ']\n'
+        f.write('\n\n__all__ = {:s}'.format(array_string))

dash/version.py

@@ -1 +1 @@
-__version__ = '0.22.1'
+__version__ = '0.23.0'