This implements the endpoint that LTI tools use to return the deep linking configuration to the LMS, along with the `ltiResourceLink` type to allow testing with demo tool.

Signed-off-by: Giovanni Cimolin da Silva <giovannicimolin@gmail.com>

Signed-off-by: Giovanni Cimolin da Silva <giovannicimolin@gmail.com>

Remove the OIDC view from XBlock and return OIDC url directly.

[BD-24] [TNL-7661] [BB-3172] LTI Improvements - Use declarative grading model on XBlock launch (#116)

* create default LineItem, WIP grade save

* add score to django admin

* WIP: find user and save grade to xblock

* boolean pragramatic grade interaction flag and optional params in enable_ags method

* Submit grades using grade signals

* lineitem urls should be optional

* lineitem is now readonly in declarative method

* test grade_submit called properly

* quality issue

* raise LTIError

* moved listener to signal.py, refactored models.py, added due and start date, updated tests.

* use load_block_as_anonymous_user and remove load_block, refactor tests

* refactor test to fix quality issue

* make lineitems_url required

* refactor tests, accept_grades_past_due on check

* test accept_grades_past_due

* add comma to last items

* refactor get_lti_ags_lineitems_url

* make sure crum returns user and not None

* nitpicks & use maximum score when given score is larger than maximum

* fix docstring of load_block_as_anonymous_user

* Move LTI 1.3 Key management to model

This:
- Removes the need to load the modulestore on every public keyset endpoint call.
- Simplifies the block structure and parent method overrides.
- Removes private key, client id and related parameters from XBlock fields

It also includes a migration from the data stored in the block to the model.

* Cleanup unused test helpers

* Version bump

* Addressing review comments

* BD-24 Implement LTI AGS Score Publish Service and Results Service

* Address PR comments and add more validation

* Address PR comments

* Add tests; Fix error with scoreMaximum; Fix quality issues; Adjust user_id results url slightly

* Add permissions tests and address other PR comments

* Fix quality test

* Address PR comments

* Add initial version of LineItem Implementation

Signed-off-by: Giovanni Cimolin da Silva <giovannicimolin@gmail.com>

* Adding tests

* Add LTI tests and fix quality isses

* Quality nit

* Add missing requirement, upgrade

* Squash migrations

* Fix merge conflicts

* Addressing review comments

* Add django url testing support

* Add tests to django views, implement compat layer

* Addressing review comments

* Improve tests and test descriptions

* Nit

Co-authored-by: Sankar Raj <sankar.raj@crystaldelta.com>

This change moves the LTI configuration retrieval to
a Django model that will LTI configuration.
The current model proxies back the to blocks to keep
backwards compatibility.

See reasoning for change at:
https://github.com/edx/xblock-lti-consumer/blob/master/docs/decisions/0001-lti-extensions-plugin.rst

This is just to keep it in line with other xblocks that define
an is_past_due attribute. Nicer if they all have the same access
pattern.

k# Please enter the commit message for your changes. Lines starting

Also fixes a few untreated exceptions and remove unused variables.

Signed-off-by: Giovanni Cimolin da Silva <giovannicimolin@gmail.com>

This commit adds support for the LTI 1.3 Access token endpoint, as detailed in the IMS Security Framework.
The token is generated using the consumer's private key (stored in the XBlock) after validating the message sent by the LTI Tool using it's public key.

Signed-off-by: Giovanni Cimolin da Silva <giovannicimolin@gmail.com>

Features:
Implement LTI 1.3 launch support.
Add LTI 1.3 passthrough views as LMS plugins.

updated bleach

Added img to bleach safe tags

Added img to bleach safe tags

Added img to bleach safe tags

added test

added test

added test

added test

added test for attr image

added test for attr image

fixed style bug

Updated format xoe

removed extra formatting

Updated to run tests on both python 2 and 3.

PROD-774

Overview
---------
This pull request makes this XBlock extensible for
adding parameters to the LTI provider in addition
to the existing ones.

Why
---
A customer needs `team` and `cohort` informaiton
to be passed through the LTI channel to simplify
integration with their LTI provider. At the same
time we'd rather not fork the XBlock, so an
Open-Closed model is needed.

More Detailed Documentation
---------------------------
I've added a couple of sections to `README.rst`
to document specifying design and
configuration steps of the new LTI parameter
processors. Please check it out for more
information about the changes that this pull
request introduces.

Example Usage
-------------
I've written a package that we'll need to use for
our customer to pass some personal user
information in addition to the cohort and team
info: https://github.com/appsembler/tahoe-lti/pull/1

Omar Al-Ithawi @ Appsembler

Add context_label and context_title to LTI POST parameters; Add required requirements; add some docker devstack instructions;