INTERNAL_SERVER_ERROR after running aws-blog-firehose-lambda locally

[dzlab]

I tried to run the Firehose java sample locally by uncommenting lines from KinesisToFirehose.java. Here is the output:

$ mvn exec:java -Dexec.mainClass="com.amazonaws.proserv.lambda.KinesisToFirehose"
...
[INFO] --- exec-maven-plugin:1.4.0:java (default-cli) @ firehoseLambda ---
Firehose ACTIVE
deliverytest
Firehose ACTIVE
Firehose ACTIVE
{RecordId: wVgtYFcO2Pv0JlXI2cN4apw3R3mxMa9kW4GaWIXR/wUa5qVqMA14XNTLsxEpzPeP0rOO5w4EqxjoZ90NcOah6lvBkoLvqMCqsZcvazNsRtKQnUzA24BG+CPxiRJCorSPZnhCmo6+NyZch4CSB0lCLUT1/AuqKN9FBgZZ9DBg7C5vQB/BcP2VfIZAHRO69Q0XbNve2eFzEqsnzLcXcO2sue6qSf5dIOUB}
...

From the output, everything looks fine, but when I check the Firehose streams on Kinesis AWS dashboard, I see this error INTERNAL_SERVER_ERROR. Now I cannot do much of anything, I don't even see manually created firehoses and the S3 bucket is still empty.