Update README file with instructions on how to test the stub

Author: yogeshnikam671

README.md

@@ -24,6 +24,32 @@ npm test
 npm run specmatic:stub
 ```
 
+### Testing the Specmatic stub
+
+Use the following curl commands to test if the stub is working as expected -
+
+1. Simple query
+```shell
+curl -X POST http://localhost:8080/graphql \
+  -H "Content-Type: application/json" \
+  -d '{
+    "query": "query { findAvailableProducts(type: gadget, pageSize: 10) { id name inventory type } }"
+  }'
+```
+
+2. Query with variables 
+```shell
+curl -X POST http://localhost:8080/graphql \
+  -H "Content-Type: application/json" \
+  -d '{
+    "query": "query FindAvailableProducts($type: ProductType!, $pageSize: Int!) { findAvailableProducts(type: $type, pageSize: $pageSize) { id name inventory type } }",
+    "variables": {
+      "type": "gadget",
+      "pageSize": 10
+    }
+  }'
+```
+
 ### Start the application
 
 ```shell

graphl_examples/createProduct.md

@@ -0,0 +1,22 @@
+request:
+  body: |
+    mutation {
+      createProduct(newProduct: {
+        name: "The Almanac",
+        inventory: 10,
+        type: book
+      }) {
+        id
+        name
+        inventory
+        type
+      }
+    }
+response: 
+  {
+    "id": "10",
+    "name": "The Almanac",
+    "inventory": 10,
+    "type": "book"
+  }
+

graphl_examples/findAvailableProductsTest.md

@@ -0,0 +1,24 @@
+request:
+  body: |
+    query {
+      findAvailableProducts(type: gadget, pageSize: 10) { 
+        id 
+        name 
+        inventory 
+        type 
+      }
+    }
+response: [
+    {
+        "id": "10",
+        "name": "The Almanac",
+        "inventory": 10,
+        "type": "book"
+    },
+    {
+        "id": "20",
+        "name": "iPhone",
+        "inventory": 15,
+        "type": "gadget"
+    }
+]

graphql_examples/createProduct.yaml

@@ -26,7 +26,7 @@
     "test": "react-scripts test --coverage --detectOpenHandles --forceExit --transformIgnorePatterns \"node_modules/(?!axios)/\"",
     "eject": "react-scripts eject",
     "graphiql": "node graphiql-server.js",
-    "specmatic:stub": "java -jar node_modules/specmatic-beta/graphql/specmatic-graphql-all.jar stub --port 8080",
+    "specmatic:stub": "java -jar node_modules/specmatic-beta/graphql/specmatic-graphql-all.jar virtualize --port 8080 --examples=graphql_examples",
     "test-ci": "cross-env SPECMATIC_LOG_LEVEL=debug DEBUG=specmatic-order-graphql-ui-react:* npm run test"
   },
   "eslintConfig": {