950 lines
35 KiB
Python
950 lines
35 KiB
Python
import logging
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import pkg_resources
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import yaml
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import os
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from functools import partial
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from lxml import etree
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from pprint import pprint
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from collections import namedtuple
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from pkg_resources import resource_listdir, resource_string, resource_isdir
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from xmodule.modulestore import Location
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from xmodule.timeparse import parse_time, stringify_time
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from xmodule.contentstore.content import StaticContent, XASSET_SRCREF_PREFIX
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from xmodule.modulestore.exceptions import ItemNotFoundError
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import time
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log = logging.getLogger('mitx.' + __name__)
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def dummy_track(event_type, event):
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pass
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class ModuleMissingError(Exception):
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pass
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class Plugin(object):
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"""
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Base class for a system that uses entry_points to load plugins.
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Implementing classes are expected to have the following attributes:
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entry_point: The name of the entry point to load plugins from
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"""
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_plugin_cache = None
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@classmethod
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def load_class(cls, identifier, default=None):
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"""
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Loads a single class instance specified by identifier. If identifier
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specifies more than a single class, then logs a warning and returns the
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first class identified.
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If default is not None, will return default if no entry_point matching
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identifier is found. Otherwise, will raise a ModuleMissingError
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"""
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if cls._plugin_cache is None:
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cls._plugin_cache = {}
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if identifier not in cls._plugin_cache:
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identifier = identifier.lower()
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classes = list(pkg_resources.iter_entry_points(
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cls.entry_point, name=identifier))
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if len(classes) > 1:
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log.warning("Found multiple classes for {entry_point} with "
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"identifier {id}: {classes}. "
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"Returning the first one.".format(
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entry_point=cls.entry_point,
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id=identifier,
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classes=", ".join(
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class_.module_name for class_ in classes)))
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if len(classes) == 0:
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if default is not None:
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return default
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raise ModuleMissingError(identifier)
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cls._plugin_cache[identifier] = classes[0].load()
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return cls._plugin_cache[identifier]
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@classmethod
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def load_classes(cls):
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"""
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Returns a list of containing the identifiers and their corresponding classes for all
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of the available instances of this plugin
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"""
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return [(class_.name, class_.load())
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for class_
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in pkg_resources.iter_entry_points(cls.entry_point)]
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class HTMLSnippet(object):
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"""
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A base class defining an interface for an object that is able to present an
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html snippet, along with associated javascript and css
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"""
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js = {}
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js_module_name = None
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css = {}
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@classmethod
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def get_javascript(cls):
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"""
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Return a dictionary containing some of the following keys:
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coffee: A list of coffeescript fragments that should be compiled and
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placed on the page
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js: A list of javascript fragments that should be included on the
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page
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All of these will be loaded onto the page in the CMS
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"""
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# cdodge: We've moved the xmodule.coffee script from an outside directory into the xmodule area of common
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# this means we need to make sure that all xmodules include this dependency which had been previously implicitly
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# fulfilled in a different area of code
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js = cls.js
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if js is None:
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js = {}
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if 'coffee' not in js:
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js['coffee'] = []
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js['coffee'].append(resource_string(__name__, 'js/src/xmodule.coffee'))
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return js
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@classmethod
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def get_css(cls):
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"""
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Return a dictionary containing some of the following keys:
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css: A list of css fragments that should be applied to the html
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contents of the snippet
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sass: A list of sass fragments that should be applied to the html
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contents of the snippet
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scss: A list of scss fragments that should be applied to the html
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contents of the snippet
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"""
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return cls.css
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def get_html(self):
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"""
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Return the html used to display this snippet
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"""
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raise NotImplementedError(
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"get_html() must be provided by specific modules - not present in {0}"
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.format(self.__class__))
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class XModule(HTMLSnippet):
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''' Implements a generic learning module.
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Subclasses must at a minimum provide a definition for get_html in order
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to be displayed to users.
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See the HTML module for a simple example.
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'''
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# The default implementation of get_icon_class returns the icon_class
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# attribute of the class
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#
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# This attribute can be overridden by subclasses, and
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# the function can also be overridden if the icon class depends on the data
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# in the module
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icon_class = 'other'
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def __init__(self, system, location, definition, descriptor,
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instance_state=None, shared_state=None, **kwargs):
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'''
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Construct a new xmodule
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system: A ModuleSystem allowing access to external resources
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location: Something Location-like that identifies this xmodule
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definition: A dictionary containing 'data' and 'children'. Both are
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optional
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'data': is JSON-like (string, dictionary, list, bool, or None,
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optionally nested).
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This defines all of the data necessary for a problem to display
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that is intrinsic to the problem. It should not include any
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data that would vary between two courses using the same problem
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(due dates, grading policy, randomization, etc.)
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'children': is a list of Location-like values for child modules that
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this module depends on
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descriptor: the XModuleDescriptor that this module is an instance of.
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TODO (vshnayder): remove the definition parameter and location--they
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can come from the descriptor.
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instance_state: A string of serialized json that contains the state of
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this module for current student accessing the system, or None if
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no state has been saved
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shared_state: A string of serialized json that contains the state that
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is shared between this module and any modules of the same type with
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the same shared_state_key. This state is only shared per-student,
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not across different students
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kwargs: Optional arguments. Subclasses should always accept kwargs and
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pass them to the parent class constructor.
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Current known uses of kwargs:
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metadata: SCAFFOLDING - This dictionary will be split into
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several different types of metadata in the future (course
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policy, modification history, etc). A dictionary containing
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data that specifies information that is particular to a
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problem in the context of a course
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'''
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self.system = system
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self.location = Location(location)
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self.definition = definition
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self.descriptor = descriptor
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self.instance_state = instance_state
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self.shared_state = shared_state
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self.id = self.location.url()
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self.url_name = self.location.name
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self.category = self.location.category
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self.metadata = kwargs.get('metadata', {})
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self._loaded_children = None
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@property
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def display_name(self):
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'''
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Return a display name for the module: use display_name if defined in
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metadata, otherwise convert the url name.
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'''
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return self.metadata.get('display_name',
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self.url_name.replace('_', ' '))
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def __unicode__(self):
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return '<x_module(id={0})>'.format(self.id)
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def get_children(self):
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'''
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Return module instances for all the children of this module.
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'''
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if self._loaded_children is None:
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child_descriptors = self.get_child_descriptors()
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children = [self.system.get_module(descriptor) for descriptor in child_descriptors]
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# get_module returns None if the current user doesn't have access
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# to the location.
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self._loaded_children = [c for c in children if c is not None]
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return self._loaded_children
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def get_child_descriptors(self):
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'''
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Returns the descriptors of the child modules
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Overriding this changes the behavior of get_children and
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anything that uses get_children, such as get_display_items.
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This method will not instantiate the modules of the children
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unless absolutely necessary, so it is cheaper to call than get_children
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These children will be the same children returned by the
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descriptor unless descriptor.has_dynamic_children() is true.
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'''
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return self.descriptor.get_children()
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def get_child_by(self, selector):
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"""
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Return a child XModuleDescriptor with the specified url_name, if it exists, and None otherwise.
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"""
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for child in self.get_children():
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if selector(child):
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return child
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return None
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def get_display_items(self):
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'''
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Returns a list of descendent module instances that will display
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immediately inside this module.
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'''
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items = []
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for child in self.get_children():
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items.extend(child.displayable_items())
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return items
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def displayable_items(self):
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'''
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Returns list of displayable modules contained by this module. If this
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module is visible, should return [self].
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'''
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return [self]
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def get_icon_class(self):
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'''
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Return a css class identifying this module in the context of an icon
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'''
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return self.icon_class
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### Functions used in the LMS
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def get_instance_state(self):
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''' State of the object, as stored in the database
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'''
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return '{}'
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def get_shared_state(self):
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'''
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Get state that should be shared with other instances
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using the same 'shared_state_key' attribute.
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'''
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return '{}'
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def get_score(self):
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"""
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Score the student received on the problem, or None if there is no
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score.
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Returns:
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dictionary
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{'score': integer, from 0 to get_max_score(),
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'total': get_max_score()}
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NOTE (vshnayder): not sure if this was the intended return value, but
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that's what it's doing now. I suspect that we really want it to just
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return a number. Would need to change (at least) capa and
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modx_dispatch to match if we did that.
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"""
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return None
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def max_score(self):
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''' Maximum score. Two notes:
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* This is generic; in abstract, a problem could be 3/5 points on one
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randomization, and 5/7 on another
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* In practice, this is a Very Bad Idea, and (a) will break some code
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in place (although that code should get fixed), and (b) break some
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analytics we plan to put in place.
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'''
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return None
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def get_progress(self):
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''' Return a progress.Progress object that represents how far the
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student has gone in this module. Must be implemented to get correct
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progress tracking behavior in nesting modules like sequence and
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vertical.
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If this module has no notion of progress, return None.
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'''
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return None
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def handle_ajax(self, dispatch, get):
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''' dispatch is last part of the URL.
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get is a dictionary-like object '''
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return ""
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# cdodge: added to support dynamic substitutions of
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# links for courseware assets (e.g. images). <link> is passed through from lxml.html parser
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def rewrite_content_links(self, link):
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# see if we start with our format, e.g. 'xasset:<filename>'
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if link.startswith(XASSET_SRCREF_PREFIX):
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# yes, then parse out the name
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name = link[len(XASSET_SRCREF_PREFIX):]
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loc = Location(self.location)
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# resolve the reference to our internal 'filepath' which
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link = StaticContent.compute_location_filename(loc.org, loc.course, name)
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return link
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def policy_key(location):
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"""
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Get the key for a location in a policy file. (Since the policy file is
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specific to a course, it doesn't need the full location url).
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"""
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return '{cat}/{name}'.format(cat=location.category, name=location.name)
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Template = namedtuple("Template", "metadata data children")
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class ResourceTemplates(object):
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@classmethod
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def templates(cls):
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"""
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Returns a list of Template objects that describe possible templates that can be used
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to create a module of this type.
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If no templates are provided, there will be no way to create a module of
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this type
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Expects a class attribute template_dir_name that defines the directory
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inside the 'templates' resource directory to pull templates from
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"""
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templates = []
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dirname = os.path.join('templates', cls.template_dir_name)
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if not resource_isdir(__name__, dirname):
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log.warning("No resource directory {dir} found when loading {cls_name} templates".format(
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dir=dirname,
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cls_name=cls.__name__,
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))
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return []
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for template_file in resource_listdir(__name__, dirname):
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if not template_file.endswith('.yaml'):
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log.warning("Skipping unknown template file %s" % template_file)
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continue
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template_content = resource_string(__name__, os.path.join(dirname, template_file))
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template = yaml.safe_load(template_content)
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templates.append(Template(**template))
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return templates
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class XModuleDescriptor(Plugin, HTMLSnippet, ResourceTemplates):
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"""
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An XModuleDescriptor is a specification for an element of a course. This
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could be a problem, an organizational element (a group of content), or a
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segment of video, for example.
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XModuleDescriptors are independent and agnostic to the current student state
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on a problem. They handle the editing interface used by instructors to
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create a problem, and can generate XModules (which do know about student
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state).
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"""
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entry_point = "xmodule.v1"
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module_class = XModule
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# Attributes for inspection of the descriptor
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stores_state = False # Indicates whether the xmodule state should be
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# stored in a database (independent of shared state)
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has_score = False # This indicates whether the xmodule is a problem-type.
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# It should respond to max_score() and grade(). It can be graded or ungraded
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# (like a practice problem).
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# A list of metadata that this module can inherit from its parent module
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inheritable_metadata = (
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'graded', 'start', 'due', 'graceperiod', 'showanswer', 'rerandomize',
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# TODO (ichuang): used for Fall 2012 xqa server access
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'xqa_key',
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# TODO: This is used by the XMLModuleStore to provide for locations for
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# static files, and will need to be removed when that code is removed
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'data_dir',
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# How many days early to show a course element to beta testers (float)
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# intended to be set per-course, but can be overridden in for specific
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# elements. Can be a float.
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'days_early_for_beta'
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)
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# cdodge: this is a list of metadata names which are 'system' metadata
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# and should not be edited by an end-user
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system_metadata_fields = ['data_dir', 'published_date', 'published_by', 'is_draft']
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# A list of descriptor attributes that must be equal for the descriptors to
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# be equal
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equality_attributes = ('definition', 'metadata', 'location',
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'shared_state_key', '_inherited_metadata')
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# Name of resource directory to load templates from
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template_dir_name = "default"
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# ============================= STRUCTURAL MANIPULATION ===================
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def __init__(self,
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system,
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definition=None,
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**kwargs):
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"""
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Construct a new XModuleDescriptor. The only required arguments are the
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system, used for interaction with external resources, and the
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definition, which specifies all the data needed to edit and display the
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problem (but none of the associated metadata that handles recordkeeping
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around the problem).
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This allows for maximal flexibility to add to the interface while
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preserving backwards compatibility.
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system: A DescriptorSystem for interacting with external resources
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definition: A dict containing `data` and `children` representing the
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problem definition
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Current arguments passed in kwargs:
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location: A xmodule.modulestore.Location object indicating the name
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and ownership of this problem
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shared_state_key: The key to use for sharing StudentModules with
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other modules of this type
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metadata: A dictionary containing the following optional keys:
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goals: A list of strings of learning goals associated with this
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module
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display_name: The name to use for displaying this module to the
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user
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url_name: The name to use for this module in urls and other places
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where a unique name is needed.
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format: The format of this module ('Homework', 'Lab', etc)
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graded (bool): Whether this module is should be graded or not
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start (string): The date for which this module will be available
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due (string): The due date for this module
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graceperiod (string): The amount of grace period to allow when
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enforcing the due date
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showanswer (string): When to show answers for this module
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rerandomize (string): When to generate a newly randomized
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instance of the module data
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"""
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self.system = system
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self.metadata = kwargs.get('metadata', {})
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self.definition = definition if definition is not None else {}
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self.location = Location(kwargs.get('location'))
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self.url_name = self.location.name
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self.category = self.location.category
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self.shared_state_key = kwargs.get('shared_state_key')
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self._child_instances = None
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self._inherited_metadata = set()
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# Class level variable
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always_recalculate_grades = False
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"""
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Return whether this descriptor always requires recalculation of grades, for
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example if the score can change via an extrnal service, not just when the
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student interacts with the module on the page. A specific example is
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FoldIt, which posts grade-changing updates through a separate API.
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"""
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@property
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def display_name(self):
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'''
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Return a display name for the module: use display_name if defined in
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metadata, otherwise convert the url name.
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'''
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return self.metadata.get('display_name',
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self.url_name.replace('_', ' '))
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@property
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def start(self):
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"""
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If self.metadata contains a valid start time, return it as a time struct.
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Else return None.
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"""
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if 'start' not in self.metadata:
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return None
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return self._try_parse_time('start')
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@start.setter
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def start(self, value):
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if isinstance(value, time.struct_time):
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self.metadata['start'] = stringify_time(value)
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@property
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def days_early_for_beta(self):
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"""
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If self.metadata contains start, return the number, as a float. Else return None.
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"""
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if 'days_early_for_beta' not in self.metadata:
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return None
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try:
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return float(self.metadata['days_early_for_beta'])
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|
except ValueError:
|
|
return None
|
|
|
|
|
|
@property
|
|
def own_metadata(self):
|
|
"""
|
|
Return the metadata that is not inherited, but was defined on this module.
|
|
"""
|
|
return dict((k, v) for k, v in self.metadata.items()
|
|
if k not in self._inherited_metadata)
|
|
|
|
@staticmethod
|
|
def compute_inherited_metadata(node):
|
|
"""Given a descriptor, traverse all of its descendants and do metadata
|
|
inheritance. Should be called on a CourseDescriptor after importing a
|
|
course.
|
|
|
|
NOTE: This means that there is no such thing as lazy loading at the
|
|
moment--this accesses all the children."""
|
|
for c in node.get_children():
|
|
c.inherit_metadata(node.metadata)
|
|
XModuleDescriptor.compute_inherited_metadata(c)
|
|
|
|
def inherit_metadata(self, metadata):
|
|
"""
|
|
Updates this module with metadata inherited from a containing module.
|
|
Only metadata specified in inheritable_metadata will
|
|
be inherited
|
|
"""
|
|
# Set all inheritable metadata from kwargs that are
|
|
# in inheritable_metadata and aren't already set in metadata
|
|
for attr in self.inheritable_metadata:
|
|
if attr not in self.metadata and attr in metadata:
|
|
self._inherited_metadata.add(attr)
|
|
self.metadata[attr] = metadata[attr]
|
|
|
|
def get_required_module_descriptors(self):
|
|
"""Returns a list of XModuleDescritpor instances upon which this module depends, but are
|
|
not children of this module"""
|
|
return []
|
|
|
|
def get_children(self):
|
|
"""Returns a list of XModuleDescriptor instances for the children of
|
|
this module"""
|
|
if self._child_instances is None:
|
|
self._child_instances = []
|
|
for child_loc in self.definition.get('children', []):
|
|
try:
|
|
child = self.system.load_item(child_loc)
|
|
except ItemNotFoundError:
|
|
log.exception('Unable to load item {loc}, skipping'.format(loc=child_loc))
|
|
continue
|
|
# TODO (vshnayder): this should go away once we have
|
|
# proper inheritance support in mongo. The xml
|
|
# datastore does all inheritance on course load.
|
|
child.inherit_metadata(self.metadata)
|
|
self._child_instances.append(child)
|
|
|
|
return self._child_instances
|
|
|
|
def get_child_by(self, selector):
|
|
"""
|
|
Return a child XModuleDescriptor with the specified url_name, if it exists, and None otherwise.
|
|
"""
|
|
for child in self.get_children():
|
|
if selector(child):
|
|
return child
|
|
return None
|
|
|
|
def xmodule_constructor(self, system):
|
|
"""
|
|
Returns a constructor for an XModule. This constructor takes two
|
|
arguments: instance_state and shared_state, and returns a fully
|
|
instantiated XModule
|
|
"""
|
|
return partial(
|
|
self.module_class,
|
|
system,
|
|
self.location,
|
|
self.definition,
|
|
self,
|
|
metadata=self.metadata
|
|
)
|
|
|
|
|
|
def has_dynamic_children(self):
|
|
"""
|
|
Returns True if this descriptor has dynamic children for a given
|
|
student when the module is created.
|
|
|
|
Returns False if the children of this descriptor are the same
|
|
children that the module will return for any student.
|
|
"""
|
|
return False
|
|
|
|
|
|
# ================================= JSON PARSING ===========================
|
|
@staticmethod
|
|
def load_from_json(json_data, system, default_class=None):
|
|
"""
|
|
This method instantiates the correct subclass of XModuleDescriptor based
|
|
on the contents of json_data.
|
|
|
|
json_data must contain a 'location' element, and must be suitable to be
|
|
passed into the subclasses `from_json` method.
|
|
"""
|
|
class_ = XModuleDescriptor.load_class(
|
|
json_data['location']['category'],
|
|
default_class
|
|
)
|
|
return class_.from_json(json_data, system)
|
|
|
|
@classmethod
|
|
def from_json(cls, json_data, system):
|
|
"""
|
|
Creates an instance of this descriptor from the supplied json_data.
|
|
This may be overridden by subclasses
|
|
|
|
json_data: A json object specifying the definition and any optional
|
|
keyword arguments for the XModuleDescriptor
|
|
|
|
system: A DescriptorSystem for interacting with external resources
|
|
"""
|
|
return cls(system=system, **json_data)
|
|
|
|
# ================================= XML PARSING ============================
|
|
@staticmethod
|
|
def load_from_xml(xml_data,
|
|
system,
|
|
org=None,
|
|
course=None,
|
|
default_class=None):
|
|
"""
|
|
This method instantiates the correct subclass of XModuleDescriptor based
|
|
on the contents of xml_data.
|
|
|
|
xml_data must be a string containing valid xml
|
|
|
|
system is an XMLParsingSystem
|
|
|
|
org and course are optional strings that will be used in the generated
|
|
module's url identifiers
|
|
"""
|
|
class_ = XModuleDescriptor.load_class(
|
|
etree.fromstring(xml_data).tag,
|
|
default_class
|
|
)
|
|
# leave next line, commented out - useful for low-level debugging
|
|
# log.debug('[XModuleDescriptor.load_from_xml] tag=%s, class_=%s' % (
|
|
# etree.fromstring(xml_data).tag,class_))
|
|
|
|
return class_.from_xml(xml_data, system, org, course)
|
|
|
|
@classmethod
|
|
def from_xml(cls, xml_data, system, org=None, course=None):
|
|
"""
|
|
Creates an instance of this descriptor from the supplied xml_data.
|
|
This may be overridden by subclasses
|
|
|
|
xml_data: A string of xml that will be translated into data and children
|
|
for this module
|
|
|
|
system is an XMLParsingSystem
|
|
|
|
org and course are optional strings that will be used in the generated
|
|
module's url identifiers
|
|
"""
|
|
raise NotImplementedError(
|
|
'Modules must implement from_xml to be parsable from xml')
|
|
|
|
def export_to_xml(self, resource_fs):
|
|
"""
|
|
Returns an xml string representing this module, and all modules
|
|
underneath it. May also write required resources out to resource_fs
|
|
|
|
Assumes that modules have single parentage (that no module appears twice
|
|
in the same course), and that it is thus safe to nest modules as xml
|
|
children as appropriate.
|
|
|
|
The returned XML should be able to be parsed back into an identical
|
|
XModuleDescriptor using the from_xml method with the same system, org,
|
|
and course
|
|
"""
|
|
raise NotImplementedError(
|
|
'Modules must implement export_to_xml to enable xml export')
|
|
|
|
# =============================== Testing ==================================
|
|
def get_sample_state(self):
|
|
"""
|
|
Return a list of tuples of instance_state, shared_state. Each tuple
|
|
defines a sample case for this module
|
|
"""
|
|
return [('{}', '{}')]
|
|
|
|
# =============================== BUILTIN METHODS ==========================
|
|
def __eq__(self, other):
|
|
eq = (self.__class__ == other.__class__ and
|
|
all(getattr(self, attr, None) == getattr(other, attr, None)
|
|
for attr in self.equality_attributes))
|
|
|
|
if not eq:
|
|
for attr in self.equality_attributes:
|
|
pprint((getattr(self, attr, None),
|
|
getattr(other, attr, None),
|
|
getattr(self, attr, None) == getattr(other, attr, None)))
|
|
|
|
return eq
|
|
|
|
def __repr__(self):
|
|
return ("{class_}({system!r}, {definition!r}, location={location!r},"
|
|
" metadata={metadata!r})".format(
|
|
class_=self.__class__.__name__,
|
|
system=self.system,
|
|
definition=self.definition,
|
|
location=self.location,
|
|
metadata=self.metadata
|
|
))
|
|
|
|
# ================================ Internal helpers =======================
|
|
|
|
def _try_parse_time(self, key):
|
|
"""
|
|
Parse an optional metadata key containing a time: if present, complain
|
|
if it doesn't parse.
|
|
|
|
Returns a time_struct, or None if metadata key is not present or is invalid.
|
|
"""
|
|
if key in self.metadata:
|
|
try:
|
|
return parse_time(self.metadata[key])
|
|
except ValueError as e:
|
|
msg = "Descriptor {0} loaded with a bad metadata key '{1}': '{2}'".format(
|
|
self.location.url(), self.metadata[key], e)
|
|
log.warning(msg)
|
|
return None
|
|
|
|
|
|
class DescriptorSystem(object):
|
|
def __init__(self, load_item, resources_fs, error_tracker, **kwargs):
|
|
"""
|
|
load_item: Takes a Location and returns an XModuleDescriptor
|
|
|
|
resources_fs: A Filesystem object that contains all of the
|
|
resources needed for the course
|
|
|
|
error_tracker: A hook for tracking errors in loading the descriptor.
|
|
Used for example to get a list of all non-fatal problems on course
|
|
load, and display them to the user.
|
|
|
|
A function of (error_msg). errortracker.py provides a
|
|
handy make_error_tracker() function.
|
|
|
|
Patterns for using the error handler:
|
|
try:
|
|
x = access_some_resource()
|
|
check_some_format(x)
|
|
except SomeProblem as err:
|
|
msg = 'Grommet {0} is broken: {1}'.format(x, str(err))
|
|
log.warning(msg) # don't rely on tracker to log
|
|
# NOTE: we generally don't want content errors logged as errors
|
|
self.system.error_tracker(msg)
|
|
# work around
|
|
return 'Oops, couldn't load grommet'
|
|
|
|
OR, if not in an exception context:
|
|
|
|
if not check_something(thingy):
|
|
msg = "thingy {0} is broken".format(thingy)
|
|
log.critical(msg)
|
|
self.system.error_tracker(msg)
|
|
|
|
NOTE: To avoid duplication, do not call the tracker on errors
|
|
that you're about to re-raise---let the caller track them.
|
|
"""
|
|
|
|
self.load_item = load_item
|
|
self.resources_fs = resources_fs
|
|
self.error_tracker = error_tracker
|
|
|
|
|
|
class XMLParsingSystem(DescriptorSystem):
|
|
def __init__(self, load_item, resources_fs, error_tracker, process_xml, policy, **kwargs):
|
|
"""
|
|
load_item, resources_fs, error_tracker: see DescriptorSystem
|
|
|
|
policy: a policy dictionary for overriding xml metadata
|
|
|
|
process_xml: Takes an xml string, and returns a XModuleDescriptor
|
|
created from that xml
|
|
"""
|
|
DescriptorSystem.__init__(self, load_item, resources_fs, error_tracker,
|
|
**kwargs)
|
|
self.process_xml = process_xml
|
|
self.policy = policy
|
|
|
|
|
|
class ModuleSystem(object):
|
|
'''
|
|
This is an abstraction such that x_modules can function independent
|
|
of the courseware (e.g. import into other types of courseware, LMS,
|
|
or if we want to have a sandbox server for user-contributed content)
|
|
|
|
ModuleSystem objects are passed to x_modules to provide access to system
|
|
functionality.
|
|
|
|
Note that these functions can be closures over e.g. a django request
|
|
and user, or other environment-specific info.
|
|
'''
|
|
def __init__(self,
|
|
ajax_url,
|
|
track_function,
|
|
get_module,
|
|
render_template,
|
|
replace_urls,
|
|
user=None,
|
|
filestore=None,
|
|
debug=False,
|
|
xqueue=None,
|
|
node_path="",
|
|
anonymous_student_id='',
|
|
course_id=None,
|
|
open_ended_grading_interface=None,
|
|
s3_interface=None):
|
|
'''
|
|
Create a closure around the system environment.
|
|
|
|
ajax_url - the url where ajax calls to the encapsulating module go.
|
|
|
|
track_function - function of (event_type, event), intended for logging
|
|
or otherwise tracking the event.
|
|
TODO: Not used, and has inconsistent args in different
|
|
files. Update or remove.
|
|
|
|
get_module - function that takes a descriptor and returns a corresponding
|
|
module instance object. If the current user does not have
|
|
access to that location, returns None.
|
|
|
|
render_template - a function that takes (template_file, context), and
|
|
returns rendered html.
|
|
|
|
user - The user to base the random number generator seed off of for this
|
|
request
|
|
|
|
filestore - A filestore ojbect. Defaults to an instance of OSFS based
|
|
at settings.DATA_DIR.
|
|
|
|
xqueue - Dict containing XqueueInterface object, as well as parameters
|
|
for the specific StudentModule:
|
|
xqueue = {'interface': XQueueInterface object,
|
|
'callback_url': Callback into the LMS,
|
|
'queue_name': Target queuename in Xqueue}
|
|
|
|
replace_urls - TEMPORARY - A function like static_replace.replace_urls
|
|
that capa_module can use to fix up the static urls in
|
|
ajax results.
|
|
|
|
anonymous_student_id - Used for tracking modules with student id
|
|
|
|
course_id - the course_id containing this module
|
|
'''
|
|
self.ajax_url = ajax_url
|
|
self.xqueue = xqueue
|
|
self.track_function = track_function
|
|
self.filestore = filestore
|
|
self.get_module = get_module
|
|
self.render_template = render_template
|
|
self.DEBUG = self.debug = debug
|
|
self.seed = user.id if user is not None else 0
|
|
self.replace_urls = replace_urls
|
|
self.node_path = node_path
|
|
self.anonymous_student_id = anonymous_student_id
|
|
self.course_id = course_id
|
|
self.user_is_staff = user is not None and user.is_staff
|
|
self.open_ended_grading_interface = open_ended_grading_interface
|
|
self.s3_interface = s3_interface
|
|
|
|
def get(self, attr):
|
|
''' provide uniform access to attributes (like etree).'''
|
|
return self.__dict__.get(attr)
|
|
|
|
def set(self, attr, val):
|
|
'''provide uniform access to attributes (like etree)'''
|
|
self.__dict__[attr] = val
|
|
|
|
def __repr__(self):
|
|
return repr(self.__dict__)
|
|
|
|
def __str__(self):
|
|
return str(self.__dict__)
|