docs: add checkpoint-change hook examples for Python and Java

docs/sdk-reference/observability/plugins.md

@@ -141,11 +141,15 @@ snapshot of all operations.
 
 === "Python"
 
-    This hook is a work in progress and is not yet available in the Python SDK.
+    ```python
+    --8<-- "examples/python/sdk-reference/plugins/checkpoint-change-hook.py"
+    ```
 
 === "Java"
 
-    This hook is a work in progress and is not yet available in the Java SDK.
+    ```java
+    --8<-- "examples/java/sdk-reference/plugins/checkpoint-change-hook.java"
+    ```
 
 ## Use a plugin
 

examples/java/sdk-reference/plugins/checkpoint-change-hook.java

@@ -0,0 +1,4 @@
+@Override
+public void onOperationChange(OperationChangeInfo info) {
+    System.out.println("operations changed, ids: " + info.updatedOperations().keySet());
+}

examples/java/sdk-reference/plugins/complete-plugin.java

@@ -3,6 +3,7 @@
 import software.amazon.lambda.durable.plugin.InvocationEndInfo;
 import software.amazon.lambda.durable.plugin.OperationInfo;
 import software.amazon.lambda.durable.plugin.OperationEndInfo;
+import software.amazon.lambda.durable.plugin.OperationChangeInfo;
 import software.amazon.lambda.durable.plugin.UserFunctionStartInfo;
 import software.amazon.lambda.durable.plugin.UserFunctionEndInfo;
 
@@ -29,6 +30,11 @@ public void onOperationEnd(OperationEndInfo info) {
         System.out.println("operation " + info.name() + " end, error: " + info.error());
     }
 
+    @Override
+    public void onOperationChange(OperationChangeInfo info) {
+        System.out.println("operations changed, ids: " + info.updatedOperations().keySet());
+    }
+
     @Override
     public void onUserFunctionStart(UserFunctionStartInfo info) {
         System.out.println("user function " + info.name() + " start, attempt: " + info.attempt());

examples/python/sdk-reference/plugins/checkpoint-change-hook.py

@@ -0,0 +1,2 @@
+def on_operation_change(self, info: OperationChangeInfo) -> None:
+    print("operations changed", "ids:", list(info.updated_operations.keys()))

examples/python/sdk-reference/plugins/complete-plugin.py

@@ -4,6 +4,7 @@
     InvocationEndInfo,
     OperationStartInfo,
     OperationEndInfo,
+    OperationChangeInfo,
     UserFunctionStartInfo,
     UserFunctionEndInfo,
 )
@@ -22,6 +23,9 @@ def on_operation_start(self, info: OperationStartInfo) -> None:
     def on_operation_end(self, info: OperationEndInfo) -> None:
         print(f"operation {info.name} end, status: {info.status}, error: {info.error}")
 
+    def on_operation_change(self, info: OperationChangeInfo) -> None:
+        print("operations changed", "ids:", list(info.updated_operations.keys()))
+
     def on_user_function_start(self, info: UserFunctionStartInfo) -> None:
         print(f"user function {info.name} start, attempt: {info.attempt}")
 

examples/typescript/sdk-reference/plugins/complete-plugin.ts

@@ -27,6 +27,10 @@ export const examplePlugin: DurableInstrumentationPlugin = {
     console.log(`operation ${info.name} end, status: ${info.status}, error: ${info.error}`);
   },
 
+  async onOperationChange(info: OperationChangeInfo): Promise<void> {
+    console.log(`operations changed, ids: ${Object.keys(info.updatedOperations)}`);
+  },
+
   async onOperationAttemptStart(info: AttemptInfo): Promise<void> {
     console.log(`attempt ${info.name} start, attempt: ${info.attempt}`);
   },
@@ -53,10 +57,6 @@ export const examplePlugin: DurableInstrumentationPlugin = {
     return fn();
   },
 
-  async onOperationChange(info: OperationChangeInfo): Promise<void> {
-    console.log(`operations changed, ids: ${Object.keys(info.updatedOperations)}`);
-  },
-
   enrichLogContext(): Record<string, string | number | boolean> {
     return { service: "orders" };
   },