Make course instance joinable with a special code (#1314)

* Regeneratable code for joining course

* Course accesses table

* Join page for joining the course via join code

* Added joinable_by_code_only to courses

* Changed join code to work with course instead of course instance

* Test and new course to seed

* Test fix

* Test fix

* Small change to a test

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Co-authored-by: Maija Y <[email protected]>

Author: Maijjay

services/headless-lms/migrations/20240930042528_add-join-code-uses.down.sql

@@ -0,0 +1,3 @@
+DROP TABLE join_code_uses;
+ALTER TABLE courses DROP COLUMN is_joinable_by_code_only;
+ALTER TABLE courses DROP COLUMN join_code;

services/headless-lms/migrations/20240930042528_add-join-code-uses.up.sql

@@ -0,0 +1,25 @@
+CREATE TABLE join_code_uses (
+  id UUID DEFAULT uuid_generate_v4() PRIMARY KEY,
+  course_id UUID NOT NULL REFERENCES courses(id),
+  user_id UUID NOT NULL REFERENCES users(id),
+  created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
+  updated_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT NOW(),
+  deleted_at TIMESTAMP WITH TIME ZONE
+);
+
+
+CREATE TRIGGER set_timestamp BEFORE
+UPDATE ON join_code_uses FOR EACH ROW EXECUTE PROCEDURE trigger_set_timestamp();
+COMMENT ON TABLE join_code_uses IS 'This table is used to check if user has access to a course that is only joinable by a join code. The join code is located in courses table';
+COMMENT ON COLUMN join_code_uses.id IS 'A unique, stable identifier for the record.';
+COMMENT ON COLUMN join_code_uses.course_id IS 'Course that the user has access to.';
+COMMENT ON COLUMN join_code_uses.user_id IS 'User who has the access to the course.';
+COMMENT ON COLUMN join_code_uses.created_at IS 'Timestamp of when the record was created';
+COMMENT ON COLUMN join_code_uses.updated_at IS 'Timestamp when the record was last updated. The field is updated automatically by the set_timestamp trigger.';
+COMMENT ON COLUMN join_code_uses.deleted_at IS 'Timestamp when the record was deleted. If null, the record is not deleted.';
+
+ALTER TABLE courses
+ADD COLUMN join_code varchar(1024),
+  ADD COLUMN is_joinable_by_code_only BOOLEAN NOT NULL DEFAULT FALSE;
+COMMENT ON COLUMN courses.join_code IS 'Regeneratable code that is used to join the course. If a user uses the code they will be added to join_code_uses -table to get access to the course';
+COMMENT ON COLUMN courses.is_joinable_by_code_only IS 'Whether this course is only joinable by a join code that can be generated for a course instance'