===== parameters received =======
    custom_canvas_user_login_id => lriddle@agnesscott.edu
    user_image => https://canvas.instructure.com/images/messages/avatar-50.png
    lti_version => LTI-1p0
    lis_result_sourcedid => 93-3388-25454-103-2f1f1947f88f3417e763c755f81c0bd73b1c370c
    oauth_signature_method => HMAC-SHA1
    custom_canvas_course_id => 3388
    custom_canvas_api_domain => agnesscott.instructure.com
    lis_person_contact_email_primary => lriddle@agnesscott.edu
    ext_outcome_submission_submitted_at_accepted => true
    tool_consumer_instance_contact_email => notifications@instructure.com
    launch_presentation_locale => en
    lti_message_type => basic-lti-launch-request
    ext_roles => urn:lti:instrole:ims/lis/Instructor,urn:lti:instrole:ims/lis/Student,urn:lti:role:ims/lis/Learner,urn:lti:sysrole:ims/lis/User
    lis_person_name_given => Larry
    tool_consumer_info_product_family_code => canvas
    tool_consumer_info_version => cloud
    oauth_timestamp => 1627496071
    custom_canvas_assignment_points_possible => 1
    custom_canvas_enrollment_state => active
    context_id => e970b3c165332c580ff521da6ee4e0f9bdf1fcec
    custom_canvas_module_item_id => 97075
    oauth_consumer_key => WeBWorK
    resource_link_title => Percentile Problem
    oauth_nonce => MEwJSWJlOc4Vg4UQLtZRW9b5Qiv73VvP3zDDitaJng
    ext_outcome_data_values_accepted => url,text
    lis_person_name_family => Riddle
    oauth_callback => about:blank
    lis_course_offering_sourcedid => MAT 115 ON SU121
    ext_ims_lis_basic_outcome_url => https://agnesscott.instructure.com/api/lti/v1/tools/93/ext_grade_passback
    launch_presentation_return_url => https://agnesscott.instructure.com/courses/3388/external_content/success/external_tool_redirect
    oauth_signature => Ar5JVM9rpOPozNU2eFueL0RhuX0=
    launch_presentation_document_target => iframe
    custom_canvas_user_id => 103
    custom_canvas_workflow_state => available
    custom_canvas_assignment_title => Percentile Problem
    custom_canvas_module_id =>
    tool_consumer_instance_guid => nnYk4VkevBXun67nxLg5Q6BD0cfCXicxOvisXcx6:canvas-lms
    lis_outcome_service_url => https://agnesscott.instructure.com/api/lti/v1/tools/93/grade_passback
    user_id => 4c743d75739ca11820b77932d2700b3a5e2c7273
    roles => Learner
    ext_outcome_result_total_score_accepted => true
    custom_canvas_assignment_id => 25454
    lis_person_name_full => Larry Riddle
    context_label => MAT 115 ON SU121
    ext_outcomes_tool_placement_url => https://agnesscott.instructure.com/api/lti/v1/turnitin/outcomes_placement/93
    resource_link_id => 68f3bc0342dce23d151676bc56fedf7acccd8929
    tool_consumer_instance_name => Agnes Scott College
    lis_person_sourcedid => 0079094
    ext_lti_assignment_id => a27ae199-bc49-407c-a863-e4f9d545d557
    oauth_version => 1.0
    context_title => Elementary Statistics
    ============================
    ===== timestamp info =======
    oauth_nonce = 1627496071
    WW_server_time = 1627496072
    diff(server-oauth) = 1 seconds (0.0166666666666667 minutes)
    ============================ at /opt/webwork/webwork2/lib/WeBWorK/Authen/LTIAdvanced.pm line 154.
    =========== summary ============ at /opt/webwork/webwork2/lib/WeBWorK/Authen/LTIAdvanced.pm line 273.
    User id is |lriddle| (obtained from lis_person_contact_email_primary which was preferred_source_of_username)
    User mail address is |lriddle@agnesscott.edu|
    strip_address_from_email is |1|
    Student id is ||
    preferred_source_of_username is |lis_person_contact_email_primary|
    fallback_source_of_username is |undefined|
    preferred_source_of_student_id is |undefined|
    ================================
    The following path was reconstructed by WeBWorK. It should match the path in the LMS: at /opt/webwork/webwork2/lib/WeBWorK/Authen/LTIAdvanced.pm line 456.
    https://webwork.agnesscott.edu/webwork2/Math115_SU21/05/ at /opt/webwork/webwork2/lib/WeBWorK/Authen/LTIAdvanced.pm line 457.

Request information
Time 	Wed Jul 28 14:14:32 2021
Method 	POST
URI 	/webwork2/Math115_SU21/05/