Fix-Nullable (#99)

fixes #99

Author: siggi-k

README.md

@@ -248,6 +248,52 @@ $this->update('{{%company}}', ['name' => 'No name']);
 $this->alterColumn('{{%company}}', 'name', $this->string(128)->notNull());
 ```
 
+### Handling of `NOT NULL` constraints (#required, #nullable)
+
+e.g. attribute = 'alpha'.
+
+1) If you define attribute neither "required" nor via "nullable", then it is by default:
+   ALLOW 'NOT NULL'
+ ```yaml
+  test_table:
+    required:
+    properties:
+      alpha:
+        type: string
+```
+
+2) If you define attribute by "required", then it is:
+   FORBIDDEN 'NOT NULL'
+ ```yaml
+  test_table:
+    required:
+     - alpha
+    properties:
+      alpha:
+        type: string
+```
+
+3) If you define attribute via "nullable", then it has the highest priority.
+   ALLOW 'NOT NULL'
+ ```yaml
+  test_table:
+    required:
+      - alpha
+    properties:
+      alpha:
+        type: string
+        nullable: true
+```
+
+FORBIDDEN 'NOT NULL'
+ ```yaml
+  test_table:
+    required:
+    properties:
+      alpha:
+        type: string
+        nullable: false
+```
 
 ## Screenshots
 

src/lib/AttributeResolver.php

@@ -204,6 +204,7 @@ protected function resolveProperty(PropertySchema $property, bool $isRequired):v
                   ->setReadOnly($property->isReadonly())
                   ->setDefault($property->guessDefault())
                   ->setXDbType($property->getAttr('x-db-type', null))
+                  ->setNullable($property->getProperty()->getSerializableData()->nullable ?? null)
                   ->setIsPrimary($property->isPrimaryKey());
         if ($property->isReference()) {
             if ($property->isVirtual()) {

src/lib/items/Attribute.php

@@ -48,9 +48,16 @@ class Attribute extends BaseObject
 
     /**
      * Custom db type
+     * string | null
      */
     public $xDbType;
 
+    /**
+     * nullable
+     * bool | null
+     */
+    public $nullable;
+
     /**
      * @var string
      */
@@ -128,9 +135,10 @@ public function setXDbType($xDbType):Attribute
         return $this;
     }
 
-    public function getXDbType($xDbType)
+    public function setNullable($nullable):Attribute
     {
-        return $this->xDbType;
+        $this->nullable = $nullable;
+        return $this;
     }
 
     public function setDescription(string $description):Attribute
@@ -263,7 +271,7 @@ public function toColumnSchema():ColumnSchema
             'phpType'=>$this->phpType,
             'dbType' => strtolower($this->dbType),
             'type' => $this->dbTypeAbstract($this->dbType),
-            'allowNull' => !$this->isRequired(),
+            'allowNull' => $this->allowNull(),
             'size' => $this->size > 0 ? $this->size : null,
         ]);
         $column->isPrimaryKey = $this->primary;
@@ -313,4 +321,12 @@ private function dbTypeAbstract(string $type):string
         }
         return $type;
     }
+
+    private function allowNull()
+    {
+        if (is_bool($this->nullable)){
+            return $this->nullable;
+        }
+        return !$this->isRequired();
+    }
 }