Allow description for submission_type_selection

why:
- To allow tools at this placement to specify an additional bit of
  description other than just title.
- Additionally, we've removed support for the
  submission_type_selection_launch_points configuration option.
  It was determined this is no longer required.

flag=none

fixes INTEROP-8478

test-plan:
- Note: This is very similar to the plan in d78cbba.
- Install the LTI 1.3 test tool (or any other tool) in the
  submission_type_selection placement.
- Modify the configuration for the submission_type_selection placement
  so that it now includes a description property. You can do this by
  editing the JSON on the dev keys page or through the Rails console
  with something like:

```ruby
tc = DeveloperKey.find(123456).tool_configuration
tc.settings["extensions"].first["settings"]["placements"].find {|p|
p.placement == "submission_type_selection}["description"] = "foobarbaz"
tc.save!
```
- It should save without causing issues.
- Go to the new Assignment page, open the web console, then type
  `ENV.SUBMISSION_TYPE_SELECTION_TOOLS` and look for the tool you
  modified. A description property should now be present with the
  description you just put in.

Change-Id: I0a032eec4202c725dea6dcea7450101c6db124b6
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/341194
Reviewed-by: Evan Battaglia <ebattaglia@instructure.com>
QA-Review: Evan Battaglia <ebattaglia@instructure.com>
Product-Review: Alexis Nast <alexis.nast@instructure.com>
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>

app/controllers/application_controller.rb

@@ -530,8 +530,8 @@ class ApplicationController < ActionController::Base
     end
     hash[:base_title] = tool.default_label(I18n.locale) if custom_settings.include?(:base_title)
     hash[:external_url] = tool.url if custom_settings.include?(:external_url)
-    if type == :submission_type_selection && tool.submission_type_selection[:submission_type_selection_launch_points].present?
-      hash[:submission_type_selection_launch_points] = tool.submission_type_selection[:submission_type_selection_launch_points]
+    if type == :submission_type_selection && tool.submission_type_selection[:description].present?
+      hash[:description] = tool.submission_type_selection[:description]
     end
 
     hash

lib/schemas/lti/tool_configuration.rb

@@ -46,32 +46,6 @@ module Schemas::Lti
         }.freeze,
       }.freeze
 
-    SUBMISSION_LAUNCH_POINTS_SCHEMA =
-      {
-        "type" => "array",
-        "items" => {
-          "type" => "object",
-          "required" => %w[target_link_uri].freeze,
-          "additionalProperties" => false,
-          "properties" => {
-            "target_link_uri" => {
-              "type" => "string",
-              "format" => "uri"
-            }.freeze,
-            "title" => {
-              "type" => "string"
-            }.freeze,
-            "icon_url" => {
-              "type" => "string",
-              "format" => "uri"
-            }.freeze,
-            "description" => {
-              "type" => "string"
-            }.freeze
-          }
-        }
-      }.freeze
-
     SCHEMA = {
       "type" => "object",
       "required" => [
@@ -159,9 +133,13 @@ module Schemas::Lti
                             "placement" => {
                               "type" => "string",
                               "pattern" => "^submission_type_selection$"
-                            },
+                            }.freeze,
+                            "description" => {
+                              "type" => "string",
+                              "maxLength" => 255,
+                              "errorMessage" => "description must be a string with a maximum length of 255 characters"
+                            }.freeze,
                             **LAUNCH_INFO_SCHEMA,
-                            "submission_type_selection_launch_points" => SUBMISSION_LAUNCH_POINTS_SCHEMA
                           }.freeze
                         }.freeze
                       ].freeze }.freeze

spec/controllers/assignments_controller_spec.rb

@@ -2297,26 +2297,19 @@ describe AssignmentsController do
           )
         end
 
-        context "the tool includes a submission_type_selection_launch_points" do
-          let(:launch_point) do
-            {
-              "target_link_uri" => "https://example.com/launch?placement=submission_type_selection",
-              "title" => "Launch",
-              "description" => "Launch the tool",
-              "icon_url" => "https://example.com/icon.png",
-            }
-          end
+        context "the tool includes a description propery" do
+          let(:description) { "This is a description" }
           let(:tool_settings) do
-            super().tap do |options|
-              options[:submission_type_selection_launch_points] = [launch_point]
-            end
+            res = super()
+            res[:description] = description
+            res
           end
 
           it "includes the launch points" do
             tool
             subject
             expect(assigns[:js_env][:SUBMISSION_TYPE_SELECTION_TOOLS][0])
-              .to include(submission_type_selection_launch_points: [launch_point])
+              .to include(description:)
           end
         end
       end

spec/models/lti/tool_configuration_spec.rb

@@ -48,18 +48,22 @@ module Lti
 
         it { is_expected.to be true }
 
-        context "with a valid submission_type_selection_launch_points" do
+        context "with a description property at the submission_type_selection placement" do
           let(:settings) do
-            super().tap do |c|
-              c["extensions"].first["settings"]["submission_type_selection_launch_points"] = [
-                {
-                  "target_link_uri" => "http://example.com/launch?placement=submission_type_selection",
-                  "title" => "Test Title",
-                  "icon_url" => "https://static.thenounproject.com/png/131630-211.png",
-                  "description" => "Test Description"
-                }
-              ]
-            end
+            res = super()
+
+            res["extensions"].first["settings"]["placements"].push(
+              {
+                "target_link_uri" => "http://example.com/launch?placement=submission_type_selection",
+                "text" => "Test Title",
+                "message_type" => "LtiResourceLinkRequest",
+                "icon_url" => "https://static.thenounproject.com/png/131630-211.png",
+                "description" => "Test Description",
+                "placement" => "submission_type_selection",
+              }
+            )
+
+            res
           end
 
           it { is_expected.to be true }
@@ -67,50 +71,44 @@ module Lti
       end
 
       context "with non-matching schema" do
-        let(:settings) do
-          s = super()
-          s.delete("target_link_uri")
-          s
-        end
-
         before do
           tool_configuration.developer_key = developer_key
         end
 
-        it { is_expected.to be false }
+        context "a missing target_link_uri" do
+          let(:settings) do
+            s = super()
+            s.delete("target_link_uri")
+            s
+          end
 
-        it "is contains a message about missing target_link_uri" do
-          tool_configuration.valid?
-          expect(tool_configuration.errors[:configuration].first.message).to include("target_link_uri,")
-        end
-      end
+          it { is_expected.to be false }
 
-      context "with an invalid submission_type_selection_launch_points" do
-        let(:settings) do
-          s = super()
-          s["extensions"].first["settings"]["placements"] << {
-            "placement" => "submission_type_selection",
-            "message_type" => "LtiResourceLinkRequest",
-            "submission_type_selection_launch_points" => [{
-              # Invalid target_link_uri
-              "target_link_uri" => "",
-              "title" => 4,
-              "icon_url" => "https://static.thenounproject.com/png/131630-211.png",
-              "description" => "Test Description"
-            }]
-          }
-          s
+          it "contains a message about a missing target_link_uri" do
+            tool_configuration.valid?
+            expect(tool_configuration.errors[:configuration].first.message).to include("target_link_uri,")
+          end
         end
 
-        before do
-          tool_configuration.developer_key = developer_key
-        end
+        context "when the submission_type_selection description is longer than 255 characters" do
+          let(:settings) do
+            s = super()
 
-        it { is_expected.to be false }
+            s["extensions"].first["settings"]["placements"].push(
+              {
+                "target_link_uri" => "http://example.com/launch?placement=submission_type_selection",
+                "text" => "Test Title",
+                "message_type" => "LtiResourceLinkRequest",
+                "icon_url" => "https://static.thenounproject.com/png/131630-211.png",
+                "description" => "a" * 256,
+                "placement" => "submission_type_selection",
+              }
+            )
 
-        it "contains a message about invalid submission_type_selection placement" do
-          tool_configuration.valid?
-          expect(tool_configuration.errors[:configuration].first.message).to include("submission_type_selection")
+            s
+          end
+
+          it { is_expected.to be false }
         end
       end