Add docs for x-no-relation and create its constant

Author: SOHELAHMED7

README.md

@@ -76,7 +76,9 @@ return $config;
 
 To use the web generator, open `index.php?r=gii` and select the `REST API Generator`.
 
-On console you can run the generator with `./yii gii/api --openApiPath=@app/openapi.yaml`. Where `@app/openapi.yaml` should be the absolute path to your OpenAPI spec file. This can be JSON as well as YAML (see also [php-openapi/php-openapi](https://github.com/php-openapi/php-openapi/) for supported formats).
+On console, you can run the generator with `./yii gii/api --openApiPath=@app/openapi.yaml`. Where `@app/openapi.yaml`
+should be the absolute path to your OpenAPI spec file. This can be JSON as well as YAML (see
+also [php-openapi/php-openapi](https://github.com/php-openapi/php-openapi/) for supported formats).
 
 Run `./yii gii/api --help` for all options. Example: Disable generation of migrations files `./yii gii/api --generateMigrations=0`
 
@@ -311,15 +313,67 @@ Provide custom database table column name in case of relationship column. This w
 
 ### `x-no-relation`
 
+To differentiate a component schema property from one-to-many or many-to-many relation in favour of array(json) of
+related objects, `x-no-relation` is used.
+
+```yaml
+        comments:
+          type: array
+          items:
+            $ref: "#/components/schemas/Comment"
+```
+
+This will not generate 'comments' column in database migrations. But it will generate `getComments()` relation in model.
+
+In order to make it real database column, extension `x-no-relation` can be used.
+
+```yaml
+        comments:
+          type: array
+          x-no-relation: true
+          items:
+            $ref: "#/components/schemas/Comment"
+```
+
+Database column type can be `array`, `json` etc. to store such data.
+
+Now if the Comment schema from the above example is
+
+```yaml
+    Comment:
+      properties:
+        id:
+          type: integer
+        content:
+          type: string
+```
+
+then the value can be
+
+```json
+[
+  {
+    "id": 1,
+    "content": "Hi there"
+  },
+  {
+    "id": 2,
+    "content": "Hi there 2"
+  }
+]
+```
+
+At this moment, `x-no-relation` can be only used with OpenAPI schema data type `array`.
+
 ## Many-to-Many relation definition
 
 There are two ways for define many-to-many relations:
 
 ### Simple many-to-many without junction model
 
    - property name for many-to-many relation should be equal lower-cased, pluralized related schema name
-     
-   - referenced schema should contains mirrored reference to current schema
+
+- referenced schema should contain mirrored reference to current schema
 
    - migration for junction table can be generated automatically - table name should be [pluralized, lower-cased
  schema_name1]2[pluralized, lower-cased schema name2], in alphabetical order;
@@ -510,12 +564,13 @@ created_at:
 ## Assumptions
 
 When generating code from an OpenAPI description there are many possible ways to achive a fitting result.
-Thus there are some assumptions and limitations that are currently applied to make this work.
+Thus, there are some assumptions and limitations that are currently applied to make this work.
 Here is a (possibly incomplete) list:
 
 - The current implementation works best with OpenAPI description that follows the [JSON:API](https://jsonapi.org/) guidelines.
   - The request and response format/schema is currently not extracted from OpenAPI schema and may need to be adjusted manually if it does not follow JSON:API
-- column/field/property with name `id` is considered as Primary Key by this library and it is automatically handled by DB/Yii; so remove it from validation `rules()`
+- column/field/property with name `id` is considered as Primary Key by this library, and it is automatically handled by
+  DB/Yii; so remove it from validation `rules()`
   - other fields can currently be used as primary keys using the `x-pk` OpenAPI extension (see below) but it may not be work correctly in all cases, please report bugs if you find them.
 
 Other things to keep in mind:

src/lib/AttributeResolver.php

@@ -218,7 +218,7 @@ protected function resolveProperty(
         }
         $attribute = Yii::createObject(Attribute::class, [$property->getName()]);
 
-        if (!empty($property->getAttr('x-no-relation'))) { // TODO custom attr
+        if (!empty($property->getAttr(CustomSpecAttr::NO_RELATION))) { // TODO custom attr
             $this->attributes[$property->getName()] = $attribute->setFakerStub($this->guessFakerStub($attribute, $property));
         }
 

src/lib/CustomSpecAttr.php

@@ -44,5 +44,5 @@ class CustomSpecAttr
     /**
      * Foreign key column name. See README for usage docs
      */
-//    public const FK_COLUMN_NAME = 'x-fk-column-name';
+    public const NO_RELATION = 'x-no-relation';
 }

src/lib/FakerStubResolver.php

@@ -421,7 +421,7 @@ public function aElementFaker($data, ?string $columnName = null): ?string
         // If you intend to use this method from out of `fakeForArray()` context then below condition should be changed depending on your use case
         // Also see OpenAPI extension `x-no-relation` in README.md
         if (!empty($compoSchemaData['properties'][$columnName]['items']['$ref'])) {
-            $compoSchemaData['properties'][$columnName]['x-no-relation'] = true;
+            $compoSchemaData['properties'][$columnName][CustomSpecAttr::NO_RELATION] = true;
         }
 
         $schema = new Schema($compoSchemaData);