What causes "Invalid resource group key: #{resource_group_key}" in instructure/canvas-lms?

Build the key as "#{resource_type}|#{resource_id}" with both values present and nil-checked

instructure/canvas-lms · error · UnsupportedResourceTypeError

Invalid resource group key: #

Error message

Invalid resource group key: #{resource_group_key}

What it means

validate_resource_group_key! splits resource_group_key on '|' and requires exactly two non-blank parts. Keys like 'WikiPage', 'WikiPage|', '|123', or with extra pipes raise UnsupportedResourceTypeError because the key cannot identify a resource type + id pair.

Solutions

Build the key as "#{resource_type}|#{resource_id}" with both values present and nil-checked
Verify format before calling: key.to_s.split('|').size == 2 and no blank parts
If an id can contain '|', use a different join scheme and update the validator accordingly
Log/inspect the offending key — the message echoes exactly what was passed

Example fix

// before
key = "WikiPage|#{page_id}" # page_id is nil => 'WikiPage|'
// after
key = [resource_type, resource_id].then { |t, i| raise 'missing id' if t.blank? || i.blank?; "#{t}|#{i}" }

Defensive patterns

Strategy: validation

Validate before calling

def valid_resource_group_key?(key)
  parts = key.to_s.split('|')
  parts.size == 2 && parts.none?(&:blank?)
end

Type guard

def parse_resource_group_key(key)
  parts = key.to_s.split('|')
  parts.size == 2 && parts.none?(&:blank?) ? parts : nil
end

Try / catch

begin
  service.convert_embed(scan_id, embed)
rescue YoutubeMigrationService::UnsupportedResourceTypeError => e
  raise ArgumentError, "malformed key: #{e.message}"
end

Prevention

Always build keys as "#{type}|#{id}" with nil-checked values
Never let ids containing '|' reach this API
Unit-test key construction with nil/empty ids

When it happens

Trigger: convert_embed with a malformed resource group key: missing id, empty type segment, an id containing a literal '|', or a key built by string concatenation with nil.

Common situations: Building the key manually as "#{type}|#{id}" where id is nil; splitting/rejoining keys incorrectly; keys copied from logs with truncation; ids that themselves contain '|' (rare, but breaks the 2-part rule).

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

Related errors

AI-assisted analysis of instructure/canvas-lms@1c9f0bb801 (2026-09-15). Data as JSON: /api/errors/13c8a0f004b0cf8a. Report an issue: GitHub.

Appendix: source

Thrown at app/services/youtube_migration_service.rb:183

    case resource_type
    when /QuizzesNext::Quiz/
      "QuizzesNext::Quiz"
    when /QuizzesNext::Bank/
      "QuizzesNext::Bank"
    else
      resource_type
    end
  end

  def validate_supported_resource!(resource_type)
    supported = SUPPORTED_RESOURCES.include?(resource_type) || NEW_QUIZZES_RESOURCES.include?(resource_type)
    raise UnsupportedResourceTypeError, "Unsupported resource type: #{resource_type}" unless supported
  end

  def validate_resource_group_key!(resource_group_key)
    parts = resource_group_key.to_s.split("|")
    if parts.size != 2 || parts.any?(&:blank?)
      raise UnsupportedResourceTypeError, "Invalid resource group key: #{resource_group_key}"
    end
  end

  def validate_resource_exists!(resource_type, resource_id)
    # We don't store New Quizzes Data in Canvas, so we can't validate their existence
    return true if NEW_QUIZZES_RESOURCES.include?(resource_type)

    case resource_type
    when "WikiPage"
      course.wiki_pages.find(resource_id)
    when "Assignment"
      course.assignments.find(resource_id)
    when "DiscussionTopic", "Announcement"
      course.discussion_topics.find(resource_id)
    when "DiscussionEntry"
      DiscussionEntry.find(resource_id)
    when "CalendarEvent"
      course.calendar_events.find(resource_id)

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