Prevent duplicate allocations for servers

CHANGELOG.md

@@ -17,6 +17,7 @@ This project follows [Semantic Versioning](http://semver.org) guidelines.
 ### Added
 * Added ability to search the following API endpoints: list users, list servers, and list locations.
 * Add support for finding a user by external ID using `/api/application/users/external/<id>` or by passing it as the search term when listing all users.
+* Added a unique key to the servers table to data integrity issues where an allocation would be assigned to more than one server at once.
  
 ### Changed
 * PHP 7.2 is now the minimum required version for this software.

app/Models/Server.php

@@ -83,7 +83,7 @@ class Server extends Model implements CleansAttributes, ValidableContract
         'io' => 'numeric|between:10,1000',
         'cpu' => 'numeric|min:0',
         'disk' => 'numeric|min:0',
-        'allocation_id' => 'exists:allocations,id',
+        'allocation_id' => 'bail|unique:servers|exists:allocations,id',
         'nest_id' => 'exists:nests,id',
         'egg_id' => 'exists:eggs,id',
         'pack_id' => 'nullable|numeric|min:0',

database/migrations/2018_02_17_134254_ensure_unique_allocation_id_on_servers_table.php

@@ -0,0 +1,32 @@
+<?php
+
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class EnsureUniqueAllocationIdOnServersTable extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        Schema::table('servers', function (Blueprint $table) {
+            $table->unique(['allocation_id']);
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        Schema::table('servers', function (Blueprint $table) {
+            $table->dropUnique(['allocation_id']);
+        });
+    }
+}