Communication: Allow recreation of a channel with same name after it's previous deletion

[badkeyy]

Checklist

General

• I tested all changes and their related features with all corresponding user types on a test server.
• Language: I followed the guidelines for inclusive, diversity-sensitive, and appreciative language.
• I chose a title conforming to the naming conventions for pull requests.

Client

• Important: I implemented the changes with a very good performance, prevented too many (unnecessary) REST calls and made sure the UI is responsive, even with large data (e.g. using paging).
• I strictly followed the principle of data economy for all client-server REST calls.
• I strictly followed the client coding and design guidelines.
• Following the theming guidelines, I specified colors only in the theming variable files and checked that the changes look consistent in both the light and the dark theme.
• I added multiple integration tests (Jest) related to the features (with a high test coverage), while following the test guidelines.
• I added authorities to all new routes and checked the course groups for displaying navigation elements (links, buttons).
• I documented the TypeScript code using JSDoc style.
• I added multiple screenshots/screencasts of my UI changes.
• I translated all newly inserted strings into English and German.

Motivation and Context

Currently it is not possible to recreate a channel with the same name than a previously deleted one without reloading the page. This PR makes this possible. Fixes #10135.

Description

I changed the distinctUntilChanged function in the channelActions$ event emitter to allow duplicate create actions

Steps for Testing

Prerequisites:

• 1 Instructor
• 1 Course with communication enabled

1. Log in to Artemis
2. Navigate to Course Communication
3. Create a new channel
4. Delete the channel
5. Recreate a channel with the same name and find that it works

Testserver States

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Review Progress

Performance Review

• I (as a reviewer) confirm that the client changes (in particular related to REST calls and UI responsiveness) are implemented with a very good performance even for very large courses with more than 2000 students.
• I (as a reviewer) confirm that the server changes (in particular related to database calls) are implemented with a very good performance even for very large courses with more than 2000 students.

Code Review

• Code Review 1
• Code Review 2

Manual Tests

• Test 1
• Test 2

Exam Mode Test

• Test 1
• Test 2

Performance Tests

• Test 1
• Test 2

Test Coverage

Screenshots

Summary by CodeRabbit

• Bug Fixes
  • Improved channel creation handling in course conversations component to ensure more responsive behavior when creating new channels.

[coderabbitai]

Walkthrough

The pull request addresses an issue with channel recreation in the course conversations component. The modification focuses on the ngOnInit method's subscription to channelActions$, specifically changing the distinctUntilChanged logic to ensure that 'create' actions are always processed, even if they appear similar to previous actions. This change aims to resolve a problem where recreating a channel with the same name after deletion was not working correctly.

Changes

File	Change Summary
src/main/webapp/app/overview/course-conversations/course-conversations.component.ts	Modified ngOnInit method's channelActions$ subscription to handle channel creation more responsively

Assessment against linked issues

Objective	Addressed	Explanation
Recreate channel with same name after deletion [#10135]	✅

Possibly related PRs

• Communication: Fix user interface reload on channel selection #9464: Modifies the same CourseConversationsComponent
• Communication: Fix visibility of create channel option for students #9989: Affects CourseConversationsComponent functionality

Suggested labels

small, bugfix, ready to merge, component:Communication

Suggested reviewers

• SimonEntholzer
• HawKhiem
• krusche
• FelberMartin

✨ Finishing Touches

• 📝 Generate Docstrings (Beta)

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[coderabbitai]

Actionable comments posted: 0

🔭 Outside diff range comments (1)

src/main/webapp/app/overview/course-conversations/course-conversations.component.ts (1)

Line range hint 282-293: Enhance error handling in channel creation.

While the error is logged to Sentry, consider adding user feedback and specific error case handling:

1. Display error messages to users
2. Handle specific error cases (e.g., temporary name conflicts during recreation)
3. Provide retry options for transient failures

     performChannelAction(channelAction: ChannelAction) {
         if (this.createChannelFn) {
             this.createChannelFn(channelAction.channel)
                 .pipe(takeUntil(this.ngUnsubscribe))
                 .subscribe({
                     complete: () => {
                         this.prepareSidebarData();
                     },
                     error: (error) => {
+                        // Log to Sentry
                         captureException('Error creating channel:', error);
+                        // Handle specific error cases
+                        const errorMessage = this.getChannelCreationErrorMessage(error);
+                        // Display user feedback (inject appropriate service)
+                        this.notificationService.error(errorMessage);
                     },
                 });
         }
     }

+    private getChannelCreationErrorMessage(error: any): string {
+        if (error.status === 409) {
+            return 'Channel creation failed. Please try again in a few moments.';
+        }
+        return 'Failed to create channel. Please try again.';
+    }

🧹 Nitpick comments (1)

src/main/webapp/app/overview/course-conversations/course-conversations.component.ts (1)

263-265: LGTM! Consider extracting the comparison function for better readability.

The modification correctly allows channel recreation by excluding 'create' actions from the distinctness check. This aligns with the PR objective to enable recreation of channels with the same name.

Consider extracting the comparison function for better readability:

+    private isEquivalentChannelAction(prev: ChannelAction, curr: ChannelAction): boolean {
+        return curr.action !== 'create' && 
+               prev.action === curr.action && 
+               prev.channel.id === curr.channel.id && 
+               prev.channel.name === curr.channel.name;
+    }

     this.channelActions$
         .pipe(
             debounceTime(500),
-            distinctUntilChanged(
-                (prev, curr) => curr.action !== 'create' && prev.action === curr.action && prev.channel.id === curr.channel.id && prev.channel.name === curr.channel.name,
-            ),
+            distinctUntilChanged(this.isEquivalentChannelAction),

📜 Review details

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Review profile: CHILL
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📥 Commits

Reviewing files that changed from the base of the PR and between dd3bda4 and b17285a.

📒 Files selected for processing (1)

• src/main/webapp/app/overview/course-conversations/course-conversations.component.ts (1 hunks)

🧰 Additional context used

📓 Path-based instructions (1)

src/main/webapp/app/overview/course-conversations/course-conversations.component.ts (1)

Pattern src/main/webapp/**/*.ts: angular_style:https://angular.io/guide/styleguide;methods_in_html:false;lazy_loading:true;code_reuse:true;tests:meaningful;types:PascalCase;enums:PascalCase;funcs:camelCase;props:camelCase;no_priv_prefix:true;strings:single_quotes;localize:true;btns:functionality;links:navigation;icons_text:newline;labels:associate;code_style:arrow_funcs,curly_braces,open_braces_same_line,indent_4;memory_leak_prevention:true;routes:naming_schema;chart_framework:ngx-charts;responsive_layout:true

⏰ Context from checks skipped due to timeout of 90000ms (2)

• GitHub Check: Codacy Static Code Analysis
• GitHub Check: client-tests

[ItsaaaMeMario]

Tested on TS4, works as expected. I didn't have to reload the page.