add apitestErrorCode doc

documentation/test-scenario/APITestErrorCode.md

@@ -0,0 +1,123 @@
+<!--
+ Copyright (c) 2021 Microsoft Corporation
+
+ This software is released under the MIT License.
+ https://opensource.org/licenses/MIT
+-->
+
+# API testing error code
+
+OAV api testing define some rules and check whether actual service response match with example. Example is very important for downstream SDK test code generation, code samples and docs. The goal to detect example quality issues and check service behaviors consistent with example.
+
+## Rule descriptions
+
+#### INCORRECT_PROVISIONING_STATE
+
+If service return 200 status code,it means the operation is succeed and finished. So the provisioning state should be one of the terminal states ["succeeded", "failed", "canceled", "ready", "created", "deleted"].
+
+The provisioning state is very important for downstream terraform or cli to manage resource status. For more details about provisioning state, please refer to this [ARM RPC provisioning state](https://github.com/Azure/azure-resource-manager-rpc/blob/master/v1.0/Addendum.md#provisioningstate-property)
+
+#### RESPONSE_MISSING_VALUE
+
+**Error message**: The response value is missing. Path: {}. Expected: {}. Actual: undefined
+
+The example has defined response value, but actually the server doesn't return that value.
+
+Example:
+
+```diff
+{
+   "properties":{
+      "targetType":"blobNfs",
+      "junctions":[
+         {
+            "namespacePath":"/blobnfs"
+         }
+      ],
+      "blobNfs":{
+         "target":"/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/scgroup/providers/Microsoft.Storage/storageAccounts/blofnfs/blobServices/default/containers/blobnfs",
+-         "usageModel":"WRITE_WORKLOAD_15"
+      }
+   }
+}
+```
+
+#### RESPONSE_ADDITIONAL_VALUE
+
+**Error message** Return additional response value. Path: {}. Expected: undefined. Actual: {}
+
+The example doesn't define the response value, but service actually return this value.
+
+Example:
+
+```diff
+{
+   "properties":{
+      "targetType":"blobNfs",
+      "junctions":[
+         {
+            "namespacePath":"/blobnfs"
+         }
+      ],
+      "blobNfs":{
+         "target":"/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/scgroup/providers/Microsoft.Storage/storageAccounts/blofnfs/blobServices/default/containers/blobnfs",
+         "usageModel":"WRITE_WORKLOAD_15"
++        "enableFeature": true
+      }
+   }
+}
+```
+
+#### RESPONSE_INCONSISTENT_VALUE
+
+**Error message** The actual response value is different from example. Path: {}. Expected: {}. Actual: {}
+
+The service returned value is different from example value.
+
+Example:
+
+```diff
+{
+   "properties":{
+      "targetType":"blobNfs",
+      "junctions":[
+         {
+            "namespacePath":"/blobnfs"
+         }
+      ],
+      "blobNfs":{
+         "target":"/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/scgroup/providers/Microsoft.Storage/storageAccounts/blofnfs/blobServices/default/containers/blobnfs",
+-         "usageModel":"WRITE_WORKLOAD_15"
++         "usageModel":"WORK_LOAD_14"
+      }
+   }
+}
+```
+
+#### ROUNDTRIP_INCONSISTENT_PROPERTY
+
+**Error message** The property's value in the response is different from what was set in the request. Path: {}. Request: {}. Response: {}
+
+Example: The sku in request parameters is `default`, but actual return is `standard`.
+
+```diff
+{
+   "parameters":{
+      "properties":{
+         "name":"myService",
+         "SKU":"default"
+      }
+   },
+   "responses":{
+      "200":{
+         "properties":{
+            "name":"myService",
++            "SKU":"standard"
+-            "SKU":"default"
+
+         }
+      }
+   }
+}
+
+```