Lambda isnt returning my body?

Question

In android studio i am passing two prompts over to my aws lambda function in order to do multi shot with nova reels. Everything seems right but i get the error below.

2025-05-21 13:56:51.261 26010-26233 LambdaInvokeNova        com.example.myroots8                 D  Received response from API
2025-05-21 13:56:51.262 26010-26233 LambdaInvokeNova        com.example.myroots8                 D  Response body: {"invocationArn": "arn:aws:bedrock:us-east-1:145023101762:async-invoke/4mjga2zmc83p", "requestId": null, "futureObjectKey": "4mjga2zmc83p/output.mp4"}
2025-05-21 13:56:51.263 26010-26233 LambdaInvokeNova        com.example.myroots8                 D  Success: {"invocationArn": "arn:aws:bedrock:us-east-1:145023101762:async-invoke/4mjga2zmc83p", "requestId": null, "futureObjectKey": "4mjga2zmc83p/output.mp4"}
2025-05-21 13:56:51.265 26010-26233 LambdaInvokeNova        com.example.myroots8                 E  Error parsing JSON: No value for body (Ask Gemini)
                                                                                                    org.json.JSONException: No value for body
                                                                                                    	at org.json.JSONObject.get(JSONObject.java:398)
                                                                                                    	at org.json.JSONObject.getString(JSONObject.java:559)
                                                                                                    	at com.example.myroots8.VcActivity$onCreate$3$1$1.onResponse(VcActivity.kt:205)
                                                                                                    	at okhttp3.internal.connection.RealCall$AsyncCall.run(RealCall.kt:529)
                                                                                                    	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
                                                                                                    	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:644)
                                                                                                    	at java.lang.Thread.run(Thread.java:1012)

Here is my Android studio code in kotlin:

if (response.isSuccessful) {
                                Log.d("LambdaInvokeNova", "Success: $responseBody")

try {

// New and improved. WORKS for futureObjectKey
                                    // Parse the JSON response
                                    val jsonResponse = JSONObject(responseBody)

// Extract the body string and parse it as JSON
                                    val bodyString = jsonResponse.getString("body")

val bodyJson = JSONObject(bodyString)

// Now extract the futureObjectKey from the body JSON
                                    if (bodyJson.has("futureObjectKey")) {
                                        val futureObjectKey = bodyJson.getString("futureObjectKey")
                                       // Log.d(
                                         //   "LambdaInvokeNova",
                                           // "futureObjectKey: $futureObjectKey"
                                        //)

// below is letting our video get created
                                        try {
                                            //Log.d(
                                              //  "LambdaInvokeNova",
                                                //"Zzzz... started sleeping. Will wake up in 2 1/2 minutes when video is ready..Zzz"
                                            //)
                                            //Thread.sleep(240000) // Sleep (block) the current thread for 4 minutes.
                                            Thread.sleep(150000) // Sleep (block) the current thread for 2 minutes 30 seconds.
                                        } catch (e: InterruptedException) {
                                            e.printStackTrace() // Handle potential interruption
                                        }

Here is my AWS Lambda function code in python 3.3:

import json
import boto3

bedrock_runtime = boto3.client("bedrock-runtime")

def lambda_handler(event, context):

body = json.loads(event['body'])
    prompt = body['prompt']
    prompt2 = body['prompt2']

model_input = {
    "taskType": "MULTI_SHOT_MANUAL",
    "multiShotManualParams": {
        "shots": [
            {"text": prompt},
            {"text": prompt2}
            
        ]
    },
    "videoGenerationConfig": {
        "seed": 33,
        "fps": 24,  # Must be 24
        "dimension": "1280x720",  # Must be "1280x720"
    },
}

try:
        # Start the asynchronous video generation job
        invocation = bedrock_runtime.start_async_invoke(
            modelId="amazon.nova-reel-v1:1",
            modelInput=model_input,
            outputDataConfig={
                "s3OutputDataConfig": {
                    "s3Uri": "s3://novabucket"
                }
            }
        )

# Extract the invocation ID and construct the future object key
        invocation_id = invocation['invocationArn'].split('/')[-1]
        future_object_key = f"{invocation_id}/output.mp4"

return {
            "statusCode": 200,
            "body": json.dumps({
                "invocationArn": invocation.get('invocationArn'),
                "requestId": invocation.get('requestId'),
                "futureObjectKey": f"{invocation_id}/output.mp4"
            })
        }

except Exception as e:
        message = str(e)
        return {
            "statusCode": 500,
            "body": json.dumps({"error": message})
        }

re:Post Agent · Answer

The issue you're experiencing is due to a mismatch between how the Lambda function is returning the response and how your Android code is trying to parse it. Your Lambda function is correctly returning a JSON object with a "body" field, but your Android code is trying to parse the entire response as if it were the body itself.

To fix this, you should modify your Android code to directly use the response body without trying to extract a nested "body" field. Here's how you can adjust your Kotlin code:

1. Remove this line:
   val bodyString = jsonResponse.getString("body")

2. Replace it with:
   val bodyJson = jsonResponse

3. Then proceed with extracting the futureObjectKey as you were doing before:
   if (bodyJson.has("futureObjectKey")) {
       val futureObjectKey = bodyJson.getString("futureObjectKey")
       // Use futureObjectKey as needed
   }

This change should resolve the "No value for body" error you're seeing. The Lambda function is already returning the data you need in the top-level JSON object, so there's no need to look for a nested "body" field.

Also, make sure your OkHttp client is configured to parse the response as a JSON object. If you're using Gson or another JSON parsing library, you might need to adjust how you're converting the response to a JSONObject.

Remember to handle potential exceptions when parsing the JSON, as the response might not always be in the expected format.  
**Sources**  
[Changing AWS Lambda Function prompt value with an event instead of changing environment variable. | AWS re:Post](https://repost.aws/questions/QUPXwYdqAoSw6Qt67TqBR4JA/changing-aws-lambda-function-prompt-value-with-an-event-instead-of-changing-environment-variable)  
[Lambda Function not returning all properties in a response via function URL. | AWS re:Post](https://repost.aws/questions/QUiTY8YO6GTkiMjmsceDq5Tw/lambda-function-not-returning-all-properties-in-a-response-via-function-url)

Lambda isnt returning my body?

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