3

I am getting the following error while building using AWS Lex? "checksum must be specified in PUT API, when the resource already exists"

Can someone tell what it means and how to fix it?

Pallav Laddha
  • 51
  • 6
  • How are you building the bot? Console? CLI? Other? I ask because I see the error someimes when I build on the console. – Scott Jul 31 '20 at 10:33

3 Answers3

2

I was getting the same error when building my bot in the console. I found the answer here.

Refresh the page and then set the version of the bot to Latest.

Scott
  • 93
  • 10
0

The documentation states that you have to provide the checksum of a bot that already exists if you are trying to update it: https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/LexModelBuildingService.html#putBot-property

"checksum — (String) Identifies a specific revision of the $LATEST version.

When you create a new bot, leave the checksum field blank. If you specify a checksum you get a BadRequestException exception.

When you want to update a bot, set the checksum field to the checksum of the most recent revision of the $LATEST version. If you don't specify the checksum field, or if the checksum does not match the $LATEST version, you get a PreconditionFailedException exception."

That's the aws-sdk for JavaScript docs, but the same concept applies to any SDK as well as the AWS CLI.

This requires calling get-bot first, which will return the checksum of the bot among other data. Save that checksum somewhere and pass it in the params when you call put-bot

I would recommend using the tutorials here: https://docs.aws.amazon.com/lex/latest/dg/gs-console.html

That tutorial demonstrates using the AWS CLI, but the same concepts can be abstracted to use any SDK you desire.

dillon.harless
  • 427
  • 4
  • 16
-1

Had the same problem. I guess once you have published one bot, you can not anymore modify or build it. Create another bot.

Arthur Robin
  • 1
  • 2
    Hey, if you are not sure of an answer, don't post it as an answer, but rather as a comment – f.khantsis Mar 29 '20 at 13:53
  • Also this is not what the documentation says: https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/LexModelBuildingService.html#putBot-property "Creates an Amazon Lex conversational bot or replaces an existing bot." I am also having this issue, even though I am providing the proper checksum. – dillon.harless Apr 14 '20 at 13:35