First basic code for currency exchange rate routines.

app/Http/Controllers/Json/ExchangeController.php

@@ -0,0 +1,60 @@
+<?php
+/**
+ * ExchangeController.php
+ * Copyright (c) 2017 thegrumpydictator@gmail.com
+ * This software may be modified and distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Http\Controllers\Json;
+
+
+use Carbon\Carbon;
+use FireflyIII\Http\Controllers\Controller;
+use FireflyIII\Models\TransactionCurrency;
+use FireflyIII\Repositories\Currency\CurrencyRepositoryInterface;
+use FireflyIII\Services\Currency\ExchangeRateInterface;
+use Illuminate\Http\Request;
+use Response;
+
+/**
+ * Class ExchangeController
+ *
+ * @package FireflyIII\Http\Controllers\Json
+ */
+class ExchangeController extends Controller
+{
+    /**
+     * @param Request             $request
+     * @param TransactionCurrency $fromCurrency
+     * @param TransactionCurrency $toCurrency
+     * @param Carbon              $date
+     */
+    public function getRate(Request $request, TransactionCurrency $fromCurrency, TransactionCurrency $toCurrency, Carbon $date)
+    {
+        /** @var CurrencyRepositoryInterface $repository */
+        $repository = app(CurrencyRepositoryInterface::class);
+        $rate       = $repository->getExchangeRate($fromCurrency, $toCurrency, $date);
+        $amount     = null;
+        if (is_null($rate->id)) {
+            $preferred = env('EXCHANGE_RATE_SERVICE', config('firefly.preferred_exchange_service'));
+            $class     = config('firefly.currency_exchange_services.' . $preferred);
+            /** @var ExchangeRateInterface $object */
+            $object = app($class);
+            $object->setUser(auth()->user());
+            $rate = $object->getRate($fromCurrency, $toCurrency, $date);
+        }
+        $return           = $rate->toArray();
+        $return['amount'] = null;
+        if (!is_null($request->get('amount'))) {
+            // assume amount is in "from" currency:
+            $return['amount'] = bcmul($request->get('amount'), $rate->rate);
+        }
+
+        return Response::json($return);
+    }
+
+}

app/Models/CurrencyExchangeRate.php

@@ -0,0 +1,53 @@
+<?php
+/**
+ * CurrencyExchange.php
+ * Copyright (c) 2017 thegrumpydictator@gmail.com
+ * This software may be modified and distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Models;
+
+
+use FireflyIII\User;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+/**
+ * Class CurrencyExchange
+ *
+ * @package FireflyIII\Models
+ */
+class CurrencyExchangeRate extends Model
+{
+
+    protected $dates = ['created_at', 'updated_at', 'date'];
+
+    /**
+     * @return BelongsTo
+     */
+    public function fromCurrency(): BelongsTo
+    {
+        return $this->belongsTo(TransactionCurrency::class, 'from_currency_id');
+    }
+
+    /**
+     * @return BelongsTo
+     */
+    public function toCurrency(): BelongsTo
+    {
+        return $this->belongsTo(TransactionCurrency::class, 'to_currency_id');
+    }
+
+    /**
+     * @return BelongsTo
+     */
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+
+}

app/Repositories/Currency/CurrencyRepository.php

@@ -14,6 +14,8 @@ declare(strict_types=1);
 namespace FireflyIII\Repositories\Currency;
 
 
+use Carbon\Carbon;
+use FireflyIII\Models\CurrencyExchangeRate;
 use FireflyIII\Models\Preference;
 use FireflyIII\Models\TransactionCurrency;
 use FireflyIII\User;
@@ -178,6 +180,28 @@ class CurrencyRepository implements CurrencyRepositoryInterface
         return $preferred;
     }
 
+    /**
+     * @param TransactionCurrency $fromCurrency
+     * @param TransactionCurrency $toCurrency
+     * @param Carbon              $date
+     *
+     * @return CurrencyExchangeRate
+     */
+    public function getExchangeRate(TransactionCurrency $fromCurrency, TransactionCurrency $toCurrency, Carbon $date): CurrencyExchangeRate
+    {
+        $rate = $this->user->currencyExchangeRates()
+                           ->where('from_currency_id', $fromCurrency->id)
+                           ->where('to_currency_id', $toCurrency->id)
+                           ->where('date', $date->format('Y-m-d'))->first();
+        if (!is_null($rate)) {
+            return $rate;
+        }
+
+        return new CurrencyExchangeRate;
+
+
+    }
+
     /**
      * @param User $user
      */

app/Repositories/Currency/CurrencyRepositoryInterface.php

@@ -14,6 +14,8 @@ declare(strict_types=1);
 namespace FireflyIII\Repositories\Currency;
 
 
+use Carbon\Carbon;
+use FireflyIII\Models\CurrencyExchangeRate;
 use FireflyIII\Models\Preference;
 use FireflyIII\Models\TransactionCurrency;
 use FireflyIII\User;
@@ -95,6 +97,15 @@ interface CurrencyRepositoryInterface
      */
     public function getCurrencyByPreference(Preference $preference): TransactionCurrency;
 
+    /**
+     * @param TransactionCurrency $fromCurrency
+     * @param TransactionCurrency $toCurrency
+     * @param Carbon              $date
+     *
+     * @return CurrencyExchangeRate
+     */
+    public function getExchangeRate(TransactionCurrency $fromCurrency, TransactionCurrency $toCurrency, Carbon $date): CurrencyExchangeRate;
+
     /**
      * @param User $user
      */

app/Services/Currency/ExchangeRateInterface.php

@@ -0,0 +1,38 @@
+<?php
+/**
+ * ExchangeRateInterface.php
+ * Copyright (c) 2017 thegrumpydictator@gmail.com
+ * This software may be modified and distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Services\Currency;
+
+
+use Carbon\Carbon;
+use FireflyIII\Models\CurrencyExchangeRate;
+use FireflyIII\Models\TransactionCurrency;
+use FireflyIII\User;
+
+interface ExchangeRateInterface
+{
+    /**
+     * @param TransactionCurrency $fromCurrency
+     * @param TransactionCurrency $toCurrency
+     * @param Carbon              $date
+     *
+     * @return CurrencyExchangeRate
+     */
+    public function getRate(TransactionCurrency $fromCurrency, TransactionCurrency $toCurrency, Carbon $date): CurrencyExchangeRate;
+
+    /**
+     * @param User $user
+     *
+     * @return mixed
+     */
+    public function setUser(User $user);
+
+}

app/Services/Currency/FixerIO.php

@@ -0,0 +1,69 @@
+<?php
+/**
+ * FixerIO.php
+ * Copyright (c) 2017 thegrumpydictator@gmail.com
+ * This software may be modified and distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Services\Currency;
+
+
+use Carbon\Carbon;
+use FireflyIII\Models\CurrencyExchangeRate;
+use FireflyIII\Models\TransactionCurrency;
+use FireflyIII\User;
+use Log;
+use Requests;
+
+/**
+ * Class FixerIO
+ *
+ * @package FireflyIII\Services\Currency
+ */
+class FixerIO implements ExchangeRateInterface
+{
+    /** @var  User */
+    protected $user;
+
+    public function getRate(TransactionCurrency $fromCurrency, TransactionCurrency $toCurrency, Carbon $date): CurrencyExchangeRate
+    {
+        $uri     = sprintf('https://api.fixer.io/%s?base=%s&symbols=%s', $date->format('Y-m-d'), $fromCurrency->code, $toCurrency->code);
+        $result  = Requests::get($uri);
+        $rate    = 1.0;
+        $content = null;
+        if ($result->status_code !== 200) {
+            Log::error(sprintf('Something went wrong. Received error code %d and body "%s" from FixerIO.', $result->status_code, $result->body));
+        }
+        // get rate from body:
+        if ($result->status_code === 200) {
+            $content = json_decode($result->body, true);
+        }
+        if (!is_null($content)) {
+            $code = $toCurrency->code;
+            $rate = isset($content['rates'][$code]) ? $content['rates'][$code] : '1';
+        }
+
+        // create new currency exchange rate object:
+        $exchangeRate = new CurrencyExchangeRate;
+        $exchangeRate->user()->associate($this->user);
+        $exchangeRate->fromCurrency()->associate($fromCurrency);
+        $exchangeRate->toCurrency()->associate($toCurrency);
+        $exchangeRate->date = $date;
+        $exchangeRate->rate = $rate;
+        $exchangeRate->save();
+
+        return $exchangeRate;
+    }
+
+    /**
+     * @param User $user
+     */
+    public function setUser(User $user)
+    {
+        $this->user = $user;
+    }
+}

app/Support/Binder/CurrencyCode.php

@@ -0,0 +1,39 @@
+<?php
+/**
+ * CurrencyCode.php
+ * Copyright (c) 2017 thegrumpydictator@gmail.com
+ * This software may be modified and distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Support\Binder;
+
+use FireflyIII\Models\TransactionCurrency;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+
+/**
+ * Class CurrencyCode
+ *
+ * @package FireflyIII\Support\Binder
+ */
+class CurrencyCode implements BinderInterface
+{
+
+    /**
+     * @param $value
+     * @param $route
+     *
+     * @return mixed
+     */
+    public static function routeBinder($value, $route)
+    {
+        $currency = TransactionCurrency::where('code', $value)->first();
+        if (!is_null($currency)) {
+            return $currency;
+        }
+        throw new NotFoundHttpException;
+    }
+}

app/User.php

@@ -15,6 +15,7 @@ declare(strict_types=1);
 namespace FireflyIII;
 
 use FireflyIII\Events\RequestedNewPassword;
+use FireflyIII\Models\CurrencyExchangeRate;
 use Illuminate\Database\Eloquent\Relations\BelongsToMany;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Database\Eloquent\Relations\HasManyThrough;
@@ -119,6 +120,14 @@ class User extends Authenticatable
         return $this->hasMany('FireflyIII\Models\Category');
     }
 
+    /**
+     * @return HasMany
+     */
+    public function currencyExchangeRates(): HasMany
+    {
+        return $this->hasMany(CurrencyExchangeRate::class);
+    }
+
     /**
      * @return HasMany
      */

config/firefly.php

@@ -134,6 +134,8 @@ return [
         'category'          => 'FireflyIII\Models\Category',
         'transaction_type'  => 'FireflyIII\Models\TransactionType',
         'currency'          => 'FireflyIII\Models\TransactionCurrency',
+        'fromCurrencyCode'  => 'FireflyIII\Support\Binder\CurrencyCode',
+        'toCurrencyCode'    => 'FireflyIII\Support\Binder\CurrencyCode',
         'limitrepetition'   => 'FireflyIII\Models\LimitRepetition',
         'budgetlimit'       => 'FireflyIII\Models\BudgetLimit',
         'piggyBank'         => 'FireflyIII\Models\PiggyBank',
@@ -207,4 +209,10 @@ return [
     'search_modifiers'           => ['amount_is', 'amount', 'amount_max', 'amount_min', 'amount_less', 'amount_more', 'source', 'destination', 'category',
                                      'budget', 'bill', 'type', 'date', 'date_before', 'date_after', 'on', 'before', 'after'],
     // tag notes has_attachments
+    'currency_exchange_services' => [
+        'fixerio'           => 'FireflyIII\Services\Currency\FixerIO',
+        'openexchangerates' => 'FireflyIII\Services\Currency\OpenExchangeRates',
+    ],
+    'preferred_exchange_service' => 'fixerio',
+
 ];

database/migrations/2017_04_13_163623_changes_for_v440.php

@@ -0,0 +1,51 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+
+/**
+ * Class ChangesForV440
+ */
+class ChangesForV440 extends Migration
+{
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        if (Schema::hasTable('currency_exchange_rates')) {
+            Schema::drop('currency_exchange_rates');
+        }
+    }
+
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        if (!Schema::hasTable('currency_exchange_rates')) {
+            Schema::create(
+                'currency_exchange_rates', function (Blueprint $table) {
+                $table->increments('id');
+                $table->timestamps();
+                $table->softDeletes();
+                $table->integer('user_id', false, true);
+                $table->integer('from_currency_id', false, true);
+                $table->integer('to_currency_id', false, true);
+                $table->date('date');
+                $table->decimal('rate', 22, 12);
+                $table->decimal('user_rate', 22, 12)->nullable();
+
+                $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
+                $table->foreign('from_currency_id')->references('id')->on('transaction_currencies')->onDelete('cascade');
+                $table->foreign('to_currency_id')->references('id')->on('transaction_currencies')->onDelete('cascade');
+            }
+            );
+        }
+
+    }
+}

routes/web.php

@@ -414,7 +414,7 @@ Route::group(
 );
 
 /**
- * JSON Controller
+ * JSON Controller(s)
  */
 Route::group(
     ['middleware' => 'user-full-auth', 'prefix' => 'json', 'as' => 'json.'], function () {
@@ -437,6 +437,9 @@ Route::group(
 
     Route::post('end-tour', ['uses' => 'JsonController@endTour', 'as' => 'end-tour']);
 
+    // currency conversion:
+    Route::get('rate/{fromCurrencyCode}/{toCurrencyCode}/{date}', ['uses' => 'Json\ExchangeController@getRate', 'as' => 'rate']);
+
 }
 );