Add grading functionality to LTI xmodule

Co-author: Alexander Kryklia <kryklia@edx.org>
Co-author: Ned Batchelder <ned@edx.org>
Co-author: Oleg Marchev <oleg@edx.org>
Co-author: Valera Rozuvan <valera@edx.org>
Co-author: polesye
[BLD-384]

docs/course_authors/source/create_lti.rst

@@ -0,0 +1,97 @@
+**********************
+Create a LTI Component
+**********************
+
+Description
+===========
+
+The LTI XModule is based on the `IMS Global Learning Tools Interoperability <http://www.imsglobal.org/LTI/v1p1p1/ltiIMGv1p1p1.html>`_ Version 1.1.1 specifications.
+
+Enabling LTI
+============
+
+It is not available from the list of general components. To turn it on, add
+"lti" to the "advanced_modules" key on the Advanced Settings page.
+
+The module supports 2 modes of operation.
+
+1. Simple display of external LTI content
+2. Display of LTI content that will be graded by external provider
+
+In both cases, before an LTI component from an external provider can be
+included in a unit, the following pieces of information must be known/decided
+upon:
+
+**LTI id** [string]
+    Internal string representing the external LTI provider. Can contain multi-
+    case alphanumeric characters, and underscore.
+
+**Client key** [string]
+    Used for OAuth authentication. Issued by external LTI provider.
+
+**Client secret** [string]
+    Used for OAuth authentication. Issued by external LTI provider.
+
+LTI id is necessary to differentiate between multiple available external LTI
+providers that are added to an edX course.
+
+The three fields above must be entered in "lti_passports" field in the format::
+
+    [
+        "{lti_id}:{client_key}:{client_secret}"
+    ]
+
+Multiple external LTI providers are separated by commas::
+
+    [
+        "{lti_id_1}:{client_key_1}:{client_secret_1}",
+        "{lti_id_2}:{client_key_2}:{client_secret_2}",
+        "{lti_id_3}:{client_key_3}:{client_secret_3}"
+    ]
+
+Adding LTI to a unit
+====================
+
+After LTI has been enabled, and an external provider has been registered, an
+instance of it can be added to a unit.
+
+LTI will be available from the Advanced Component category. After adding an LTI
+component to a unit, it can be configured by Editing it's settings (the Edit
+dialog). The following settings are available:
+
+**Display Name** [string]
+    Title of the new LTI component instance
+
+**custom_parameters** [string]
+    With the "+ Add" button, multiple custom parameters can be
+    added. Basically, each individual external LTI provider can have a separate
+    format custom parameters. For example::
+
+        key=value
+
+**graded** [boolean]
+    Whether or not the grade for this particular LTI instance problem will be
+    counted towards student's total grade.
+
+**launch_url** [string]
+    If `rgaded` above is set to `true`, then this must be
+    the URL that will be passed to the external LTI provider for it to respond with
+    a grade.
+
+**lti_id** [string]
+    Internal string representing the external LTI provider that
+    will be used to display content. The same as was entered on the Advanced
+    Settings page.
+
+**open_in_a_new_page** [boolean]
+    If set to `true`, a link will be present for the student
+    to click. When the link is clicked, a new window will open with the external
+    LTI content. If set to `false`, the external LTI content will be loaded in the
+    page in an iframe.
+
+**weight** [float]
+    If the problem will be graded by an external LTI provider,
+    the raw grade will be in the range [0.0, 1.0]. In order to change this range,
+    set the `weight`. The grade that will be stored is calculated by the formula::
+
+        stored_grade = raw_grade * weight

docs/course_authors/source/index.rst

@@ -20,6 +20,7 @@ Contents
    create_video
    create_discussion
    create_html_component
+   create_lti
    create_problem
    set_content_releasedates
    establish_course_settings
@@ -34,13 +35,13 @@ Contents
    checking_student_progress
    change_log
 
-   
-
-  
 
 
 
-Appendices 
+
+
+
+Appendices
 ==========
 
 .. toctree::