Database Setup

Cloning the repo

1. Clone the repo to ~/Code/Laravel
2. cd into the cloned repo in your VM
3. Run composer install to install PHP dependencies
4. Run npm install to install Node.js dependencies
5. Copy .env.example to .env
6. In .env, set APP_KEY to a random 32-character string

Playing with the database

Last updated: Mon Mar 20 20:43:08 EDT 2017

Currently the base models are not merged with master so we'll need to checkout the 'firstModels' branch.

1. git pull
2. git checkout origin/firstModels

From the root directory of the project run the following commands.

1. php artisan migrate:install

Expected output

Migration table created successfully.

2. php artisan migrate Expected output

Migrated: 2014_10_12_000000_create_users_table 
Migrated: 2014_10_12_100000_create_password_resets_table 
Migrated: 2017_02_14_204134_create_courses_table 
Migrated: 2017_02_15_034244_create_courses_users_table 
Migrated: 2017_03_09_015134_create_repositories_table 
Migrated: 2017_03_09_034837_create_repositories_users_table 
Migrated: 2017_03_15_002742_create_assignments_table 
Migrated: 2017_03_15_004119_create_submissions_table 

Now seed the database with mock data: 3. php artisan db:seed

You might receive an error about reflection or unable to find UsersTableSeeder

To remedy this run the following command:

composer dump-autoload

then run the seed command again.

Expected output:

Seeding: UsersTableSeeder
Seeding: CoursesTableSeeder

Cool, now the database is now seeded with some mock data. Lets Inspect it.

4. mysql -u homestead

You'll be in an interactive mysql session. To display all the databases run the following command.

5. show databases;

+--------------------+
| Database           |
+--------------------+
| homestead          |
| information_schema |
| mysql              |
| performance_schema |
+--------------------+

For any future operations we want to use the homestead database.

6. use homestead;

View all the tables:

7. show tables;

+---------------------+
| Tables_in_homestead |
+---------------------+
| assignments         |
| courses             |
| courses_users       |
| migrations          |
| password_resets     |
| repositories        |
| repositories_users  |
| submissions         |
| users               |
+---------------------+

Use the following command to view the random courses that have been generated:

8. select * from courses;

+----+----------+----------+--------+---------------------+---------------------+
| id | name     | slug     | active | created_at          | updated_at
+----+----------+----------+--------+---------------------+---------------------+
|  1 | CIS876   | CIS876   |      1 | 2017-03-20 23:59:22 | 2017-03-20 23:59:22
|  2 | MATH4702 | MATH4702 |      1 | 2017-03-20 23:59:22 | 2017-03-20 23:59:22
|  3 | CIS5916  | CIS5916  |      1 | 2017-03-20 23:59:22 | 2017-03-20 23:59:22
|  4 | MATH7174 | MATH7174 |      1 | 2017-03-20 23:59:22 | 2017-03-20 23:59:22
|  5 | STAT6183 | STAT6183 |      1 | 2017-03-20 23:59:22 | 2017-03-20 23:59:22
|  6 | CIS6056  | CIS6056  |      1 | 2017-03-20 23:59:29 | 2017-03-20 23:59:29
|  7 | STAT6373 | STAT6373 |      1 | 2017-03-20 23:59:30 | 2017-03-20 23:59:30
+----+----------+----------+--------+---------------------+---------------------+

Feel free to explore the other tables. The only ones that aren't seeded are repository related.

Exit the sql interpretor

9. quit;

Then run

10. php artisan tinker

Tinker is a great environment for poking and playing around with components in Laravel. Let's play around with the Course model located in app/Course

This will return a collection of all the courses in the database. 11. $courses = App\Course::get();

Lets play around with course 5.

12. $course = $courses[4];

If we look at the at app\Course.php, we can see that theres a function to get the assignments for a course. Let's try calling it.

13. $course->assignments();

Notice how we get an object that's an instance of HasMany. It's not what we were expecting.

=> Illuminate\Database\Eloquent\Relations\HasMany {#658}

The class HasMany is inherited from the abstract class Relation. The Relation class contains a member called query which is an instance of Builder. Relation is implemented in such a way that we can call Builder methods on it. This allows us to use the 'get' method to obtain the results of the query.

14. $course->assignments()->get();

What are the benefits to returning an instance of Builder or Relation? It allows us to save trips to the database and we can build more complex queries.

For Example: I want to get all the instructors for a course and order them by their names.

15. $course->enrollments()->where('role', 'instructor')->orderBy('name')->get();

Feel free to play around with all the other models in Tinker.

Etc

Q: I broke my database and can't migrate any more

Run the following Commands:

1. mysql -u homestead
2. drop database homestead;
3. create database homestead;
4. quit;
5. php artisan migrate:install
6. php artisan migrate

This should place your database in a fresh state.