instructure/canvas-lms · error · ArgumentError

Missing required parameter: course

Error message

Missing required parameter: course

What it means

Lti::Pns::LtiContextCopyNoticeBuilder's initialize requires params[:course]; if absent it raises ArgumentError "Missing required parameter: course". A context-copy PNS notice cannot be rendered without knowing which course was copied, so the builder fails fast at construction time.

Solutions

1. Pass the loaded Course object (or whatever type :course expects) as params[:course] when constructing the builder.
2. Verify the course still exists before scheduling/building the notice; skip the notice if it was deleted.
3. Check the caller is passing the Course record, not just a course id, under the :course key.
4. Wrap construction in a check: build the notice only if params[:course].present?.

Example fix

// before
Lti::Pns::LtiContextCopyNoticeBuilder.new({ copied_at: time })
// after
Lti::Pns::LtiContextCopyNoticeBuilder.new({ course: course, copied_at: time })

return nil unless params[:course].present?
Lti::Pns::LtiContextCopyNoticeBuilder.new(params)

begin
  Lti::Pns::LtiContextCopyNoticeBuilder.new(params)
rescue ArgumentError => e
  Rails.logger.warn("context copy notice skipped: #{e.message}")
end

When it happens

Trigger: Calling Lti::Pns::LtiContextCopyNoticeBuilder.new without a :course key, or with course: nil — e.g. when the copy job runs after the source/destination course lookup returned nil or the course was deleted.

Common situations: Course copy/import jobs enqueued before a hard-delete removed the course; passing the wrong hash (e.g. the job options hash) as params; key renames like course_id vs course.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

• Missing required asset parameter #
• Missing required parameter: copied_at
• Missing required parameter: #
• e.message
• Validation failed: Notice type unknown, must be one of

AI-assisted analysis of instructure/canvas-lms@1c9f0bb801 (2026-09-15). Data as JSON: /api/errors/02efaffd74785fc2. Report an issue: GitHub.

Appendix: source

Thrown at app/models/lti/pns/lti_context_copy_notice_builder.rb:26

# Canvas is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, version 3 of the License.
#
# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see <http://www.gnu.org/licenses/>.

module Lti
  module Pns
    class LtiContextCopyNoticeBuilder < NoticeBuilder
      attr_reader :params

      def initialize(params = {})
        raise ArgumentError, "Missing required parameter: course" unless params[:course]
        raise ArgumentError, "Missing required parameter: copied_at" unless params[:copied_at]

        @params = params
        super()
      end

      def notice_type
        Lti::Pns::NoticeTypes::CONTEXT_COPY
      end

      def custom_instructure_claims(_tool)
        {}
      end

      def custom_ims_claims(_tool)
        course = params[:course]

        context = {

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