Voting system (#199)

* Created migration, the Sitting and Question models and seeders for them.

* Finished models (factories not yet); created skeleton controller and policy

* Starting with basic UI at /voting

* Applying small changes to database structure; fixing new question panel

* Bringing it to a working state

* Format code with php-cs-fixer

* Format code with php-cs-fixer

* Applying most of the requested changes

* Applying Deepsource suggestions

* Adding doc comments

* Format code with php-cs-fixer

* Using CRUD route name conventions

* Moving voting to Question model; updating migration accordingly

* Format code with php-cs-fixer

* Revert "Merge branch 'development' into voting"

This reverts commit e1a7dcf, reversing
changes made to 72e0169.

* improve migration

* improve backend

* improve frontend

* Format code with php-cs-fixer

* tests

* Format code with php-cs-fixer

* Revert "Revert "Merge branch 'development' into voting""

This reverts commit 5e79389.

* fix tests

* Adding passcode to questions

* Adding random passcode generation to QuestionFactory

* Opening view_question UI to all voters

---------

Co-authored-by: deepsource-autofix[bot] <62050782+deepsource-autofix[bot]@users.noreply.github.com>
Co-authored-by: Katkó Dominik <[email protected]>
Co-authored-by: katkodominik <[email protected]>

app/Http/Controllers/StudentsCouncil/VotingController.php

@@ -0,0 +1,233 @@
+<?php
+
+namespace App\Http\Controllers\StudentsCouncil;
+
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\Auth;
+use Illuminate\Support\Facades\Validator;
+use App\Http\Controllers\Controller;
+use App\Models\Voting\Sitting;
+use App\Models\Voting\Question;
+use App\Models\Voting\QuestionOption;
+
+class VotingController extends Controller
+{
+    /**
+     * Lists sittings.
+     */
+    public function index()
+    {
+        $this->authorize('viewAny', Sitting::class);
+        return view('student-council.voting.list', [
+            "sittings" => Sitting::orderByDesc('opened_at')->get()
+        ]);
+    }
+
+    /**
+     * Returns the 'new sitting' page.
+     */
+    public function newSitting()
+    {
+        $this->authorize('administer', Sitting::class);
+        return view('student-council.voting.new_sitting');
+    }
+
+    /**
+     * Saves a new sitting.
+     */
+    public function addSitting(Request $request)
+    {
+        $this->authorize('administer', Sitting::class);
+
+        $validator = Validator::make($request->all(), [
+            'title' => 'required|string',
+        ]);
+        $validator->validate();
+
+        $sitting = Sitting::create([
+            'title' => $request->title,
+            'opened_at' => now(),
+        ]);
+
+        return view('student-council.voting.view_sitting', [
+            "sitting" => $sitting
+        ]);
+    }
+
+    /**
+     * Returns a page with the details and questions of a sitting.
+     */
+    public function viewSitting(Sitting $sitting)
+    {
+        $this->authorize('viewAny', Sitting::class);
+
+        return view('student-council.voting.view_sitting', [
+            "sitting" => $sitting
+        ]);
+    }
+
+    /**
+     * Closes a sitting.
+     */
+    public function closeSitting(Sitting $sitting)
+    {
+        $this->authorize('administer', Sitting::class);
+        if (!$sitting->isOpen()) {
+            abort(401, "tried to close a sitting which was not open");
+        }
+        $sitting->close();
+        return back()->with('message', __('voting.sitting_closed'));
+    }
+
+    /**
+     * Returns the 'new question' page.
+     */
+    public function newQuestion(Request $request)
+    {
+        $this->authorize('administer', Sitting::class);
+
+        $validator = Validator::make($request->all(), [
+            'sitting' => 'exists:sittings,id',
+        ]);
+        $validator->validate();
+        $sitting = Sitting::findOrFail($request->sitting);
+
+        if (!$sitting->isOpen()) {
+            abort(401, "tried to modify a sitting which was not open");
+        }
+        return view('student-council.voting.new_question', [
+            "sitting" => $sitting
+        ]);
+    }
+
+    /**
+     * Saves a new question.
+     */
+    public function addQuestion(Request $request)
+    {
+        $this->authorize('administer', Sitting::class);
+
+        $validator = Validator::make($request->all(), [
+            'sitting' => 'exists:sittings,id',
+            'title' => 'required|string',
+            'max_options' => 'required|min:1',
+            'options' => 'required|array|min:1',
+            'options.*' => 'nullable|string|max:255',
+        ]);
+        $options = array_filter($request->options, function ($s) {
+            return $s != null;
+        });
+        if (count($options)==0) {
+            $validator->after(function ($validator) {
+                $validator->errors()->add('options', __('voting.at_least_one_option'));
+            });
+        }
+        $validator->validate();
+        $sitting = Sitting::findOrFail($request->sitting);
+
+        if (!$sitting->isOpen()) {
+            abort(401, "tried to modify a sitting which was not open");
+        }
+
+        $question = $sitting->questions()->create([
+            'title' => $request->title,
+            'max_options' => $request->max_options,
+            'opened_at' => now(),
+            'passcode' => \Str::random(8)
+        ]);
+        foreach ($options as $option) {
+            $question->options()->create([
+                'title' => $option,
+                'votes' => 0
+            ]);
+        }
+
+        return redirect()->route('questions.show', $question)->with('message', __('general.successful_modification'));
+    }
+
+    /**
+     * Closes a question.
+     */
+    public function closeQuestion(Question $question)
+    {
+        $this->authorize('administer', Sitting::class);
+        if (!$question->isOpen()) {
+            abort(401, "tried to close a question which was not open");
+        }
+        $question->close();
+        return back()->with('message', __('voting.question_closed'));
+    }
+
+    /**
+     * Returns a page with the options (and results, if authorized) of a question.
+     */
+    public function viewQuestion(Question $question)
+    {
+        $this->authorize('viewAny', Sitting::class);
+        return view('student-council.voting.view_question', [
+            "question" => $question
+        ]);
+    }
+
+    /**
+     * Returns the voting page.
+     */
+    public function vote(Question $question)
+    {
+        $this->authorize('vote', $question);
+        return view('student-council.voting.vote', [
+            "question" => $question
+        ]);
+    }
+
+    /**
+     * Saves a vote.
+     */
+    public function saveVote(Question $question, Request $request)
+    {
+        $this->authorize('vote', $question); //this also checks whether the user has already voted
+
+        if ($question->isMultipleChoice()) {
+            $validator = Validator::make($request->all(), [
+                'option' => 'array|max:'.$question->max_options,
+                'option.*' => 'exists:question_options,id',
+                'passcode' => 'string'
+            ]);
+            if ($request->passcode!=$question->passcode) {
+                $validator->after(function ($validator) {
+                    $validator->errors()->add('passcode', __('voting.incorrect_passcode'));
+                });
+            }
+            $validator->validate();
+
+            $options = array();
+            foreach ($request->option as $oid) {
+                $option = QuestionOption::findOrFail($oid);
+                if ($option->question_id != $question->id) {
+                    abort(401, "Tried to vote for an option which does not belong to the question");
+                }
+                array_push($options, $option);
+            }
+            $question->vote(Auth::user(), $options);
+        } else {
+            $validator = Validator::make($request->all(), [
+                'option' => 'exists:question_options,id',
+                'passcode' => 'string'
+            ]);
+            if ($request->passcode!=$question->passcode) {
+                $validator->after(function ($validator) {
+                    $validator->errors()->add('passcode', __('voting.incorrect_passcode'));
+                });
+            }
+            $validator->validate();
+
+            $option = QuestionOption::findOrFail($request->option);
+            if ($option->question->id!=$question->id) {
+                abort(401, "Tried to vote for an option which does not belong to the question");
+            }
+            $question->vote(Auth::user(), array($option));
+        }
+
+        return redirect()->route('sittings.show', $question->sitting)->with('message', __('voting.successful_voting'));
+    }
+}

app/Models/Voting/Question.php

@@ -0,0 +1,138 @@
+<?php
+
+namespace App\Models\Voting;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+
+use Illuminate\Database\Eloquent\Relations\HasMany;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Support\Facades\DB;
+use App\Models\Voting\Sitting;
+use App\Models\Voting\QuestionOption;
+use App\Models\Voting\QuestionUser;
+use App\Models\User;
+
+class Question extends Model
+{
+    use HasFactory;
+
+    protected $fillable = ['title', 'sitting_id', 'max_options', 'opened_at', 'closed_at', 'passcode'];
+
+    public $timestamps = false;
+
+    /**
+     * @return BelongsTo The parent sitting.
+     */
+    public function sitting(): BelongsTo
+    {
+        return $this->belongsTo(Sitting::class);
+    }
+
+    /**
+     * @return HasMany the options belonging to the question
+     */
+    public function options(): HasMany
+    {
+        return $this->hasMany(QuestionOption::class);
+    }
+
+    /**
+     * @return bool Whether the question has already been opened once (regardless of whether it has been closed since then).
+     */
+    public function hasBeenOpened(): bool
+    {
+        return $this->opened_at!=null && $this->opened_at<=now();
+    }
+
+    /**
+     * @return bool Whether the question is currently open.*
+     */
+    public function isOpen(): bool
+    {
+        return $this->hasBeenOpened() &&
+                !$this->isClosed();
+    }
+    /**
+     * @return bool Whether the question has been closed.
+     */
+    public function isClosed(): bool
+    {
+        return $this->closed_at!=null && $this->closed_at<=now();
+    }
+
+    /**
+     * Opens the question.
+     * @throws Exception if it has already been opened.
+     */
+    public function open(): void
+    {
+        if (!$this->sitting->isOpen()) {
+            throw new \Exception("tried to open question when sitting was not open");
+        }
+        if ($this->isOpen() || $this->isClosed()) {
+            throw new \Exception("tried to open question when it has already been opened");
+        }
+        $this->update(['opened_at'=>now()]);
+    }
+
+    /**
+     * Closes the question.
+     * @throws Exception if it has already been closed or if it is not even open.
+     */
+    public function close(): void
+    {
+        if ($this->isClosed()) {
+            throw new \Exception("tried to close sitting when it has already been closed");
+        }
+        if (!$this->isOpen()) {
+            throw new \Exception("tried to close sitting when it was not open");
+        }
+        $this->update(['closed_at'=>now()]);
+    }
+
+    /**
+     * @return book Whether the question is a multiple-choice question (with checkboxes).
+     */
+    public function isMultipleChoice(): bool
+    {
+        return $this->max_options>1;
+    }
+
+    /**
+     * @param User $user
+     * @return bool Whether a certain user has already voted in the question.
+     */
+    public function hasVoted(User $user): bool
+    {
+        return QuestionUser::where('question_id', $this->id)->where('user_id', $user->id)->exists();
+    }
+
+    /**
+     * Votes for a list of given options in the name of the user.
+     * @param User $user
+     * @param array $options QuestionOption array
+     * @throws Exception if an option does not belong to the question or if too many options are selected.
+     */
+    public function vote(User $user, array $options): void
+    {
+        if (!$this->isOpen()) {
+            throw new \Exception("question not open");
+        }
+        if ($this->max_options < count($options)) {
+            throw new \Exception("too many options given");
+        }
+        DB::transaction(function () use ($user, $options) {
+            QuestionUser::create([
+                'question_id' => $this->id,
+                'user_id' => $user->id,
+            ]);
+            foreach ($options as $option) {
+                if ($option->question_id != $this->id) {
+                    throw new \Exception("Received an option which does not belong to the question");
+                }
+                $option->increment('votes');
+            }
+        });
+    }
+}

app/Models/Voting/QuestionOption.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Models\Voting;
+
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+
+use App\Models\Voting\Question;
+
+class QuestionOption extends Model
+{
+    use HasFactory;
+
+    public $timestamps = false;
+
+    protected $fillable = ['question_id', 'title', 'votes'];
+
+    /**
+     * @return BelongsTo The question the option belongs to.
+    */
+    public function question(): BelongsTo
+    {
+        return $this->belongsTo(Question::class);
+    }
+}