# Example Using GraphQL

### Toy Store API with GraphQL: A Hands-on Example

This example showcases a basic GraphQL API for a toy store, demonstrating the schema, queries, and mutations.

#### Schema:

```graphql
type Toy {
  id: ID!
  name: String!
  price: Float!
  category: String!
  inStock: Boolean!
}

type Query {
  toys(category: String): [Toy!]!
  toy(id: ID!): Toy
}

type Mutation {
  createToy(name: String!, price: Float!, category: String!): Toy!
}
```

#### Explanation:

* **Types:**
  * `Toy`: Represents a toy object with properties like `id`, `name`, `price`, `category`, and `inStock`.
  * `Query`: Defines available data retrieval operations.
  * `Mutation`: Defines data manipulation operations (optional, not all APIs have mutations).
* **Query:**
  * `toys(category: String)`: Retrieves a list of toys based on an optional category filter.
  * `toy(id: ID!)`: Fetches a specific toy by its ID.
* **Mutation:**
  * `createToy(name: String!, price: Float!, category: String!)`: Creates a new toy with provided details.

**Query Example (Get all toys):**

```graphql
query {
  toys
}
```

#### Response:

```graphql
{
  "data": {
    "toys": [
      {
        "id": "1",
        "name": "Stuffed Bear",
        "price": 19.99,
        "category": "Plushies",
        "inStock": true
      },
      {
        "id": "2",
        "name": "Remote Control Car",
        "price": 49.99,
        "category": "Vehicles",
        "inStock": false
      }
    ]
  }
}

```

**Query Example (Get a toy by ID):**

```graphql
query getToy($id: ID!) {
  toy(id: $id) {
    id
    name
    price
  }
}
```

**Variables:**

```graphql
{
  "id": "1"
}
```

**Response:**

```graphql
{
  "data": {
    "toy": {
      "id": "1",
      "name": "Stuffed Bear",
      "price": 19.99
    }
  }
}
```

**Mutation Example (Create a new toy):**

```graphql
mutation createToy($name: String!, $price: Float!, $category: String!) {
  createToy(name: $name, price: $price, category: $category) {
    id
    name
    price
    category
  }
}
```

#### Variables:

```graphql
{
  "name": "Building Blocks",
  "price": 24.99,
  "category": "Construction"
}
```

#### Response:

```graphql
{
  "data": {
    "createToy": {
      "id": "3",  // Generated by the server
      "name": "Building Blocks",
      "price": 24.99,
      "category": "Construction"
    }
  }
}
```

This example demonstrates the fundamental concepts of using a GraphQL API. By understanding the schema, you can craft queries to retrieve specific data and potentially use mutations to interact with the data (if supported).