# Cannot set property 'S3Key' of undefined **URL:** \ **Category:** Serverless Framework\ **Tags:** aws\ **Created:** [November 14, 2017, 3:35pm UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102 "2017-11-14T15:35:43Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![efenderbosch](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.serverless.com/efenderbosch/32/1269_2.png) [@efenderbosch](https://forum.serverless.com/u/efenderbosch)\ **Post date:** [November 14, 2017, 3:35pm UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102/1 "2017-11-14T15:35:43Z")
Output of serverless deploy --debug w/ SLS\_DEBUG=’\*’ No idea what to look for. Any help would be appreciated. ``` Type Error --------------------------------------------- ``` Cannot set property ‘S3Key’ of undefined ``` For debugging logs, run again after setting the "SLS_DEBUG=*" environment variable. ``` Stack Trace -------------------------------------------- TypeError: Cannot set property ‘S3Key’ of undefined at \_.forEach (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/lib/normalizeFiles.js:13:38) at /usr/local/lib/node\_modules/serverless/node\_modules/lodash/lodash.js:4944:15 at baseForOwn (/usr/local/lib/node\_modules/serverless/node\_modules/lodash/lodash.js:3001:24) at /usr/local/lib/node\_modules/serverless/node\_modules/lodash/lodash.js:4913:18 at Function.forEach (/usr/local/lib/node\_modules/serverless/node\_modules/lodash/lodash.js:9359:14) at Object.normalizeCloudFormationTemplate (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/lib/normalizeFiles.js:10:7) at AwsDeploy.checkIfDeploymentIsNecessary (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/deploy/lib/checkForChanges.js:89:45) From previous event: at AwsDeploy.checkForChanges (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/deploy/lib/checkForChanges.js:22:8) From previous event: at Object.aws:deploy:deploy:checkForChanges [as hook] (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/deploy/index.js:102:10) at BbPromise.reduce (/usr/local/lib/node\_modules/serverless/lib/classes/PluginManager.js:360:55) From previous event: at PluginManager.invoke (/usr/local/lib/node\_modules/serverless/lib/classes/PluginManager.js:360:22) at PluginManager.spawn (/usr/local/lib/node\_modules/serverless/lib/classes/PluginManager.js:378:17) at AwsDeploy.BbPromise.bind.then (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/deploy/index.js:91:48) From previous event: at Object.deploy:deploy [as hook] (/usr/local/lib/node\_modules/serverless/lib/plugins/aws/deploy/index.js:87:10) at BbPromise.reduce (/usr/local/lib/node\_modules/serverless/lib/classes/PluginManager.js:360:55) From previous event: at PluginManager.invoke (/usr/local/lib/node\_modules/serverless/lib/classes/PluginManager.js:360:22) at PluginManager.run (/usr/local/lib/node\_modules/serverless/lib/classes/PluginManager.js:391:17) at variables.populateService.then (/usr/local/lib/node\_modules/serverless/lib/Serverless.js:99:33) at runCallback (timers.js:666:20) at tryOnImmediate (timers.js:639:5) at processImmediate [as \_immediateCallback] (timers.js:611:5) From previous event: at Serverless.run (/usr/local/lib/node\_modules/serverless/lib/Serverless.js:86:74) at serverless.init.then (/usr/local/lib/node\_modules/serverless/bin/serverless:39:50) ---
**Author:** ![trevorhreed](https://avatars.discourse-cdn.com/v4/letter/t/0ea827/32.png) [@trevorhreed](https://forum.serverless.com/u/trevorhreed)\ **Post date:** [January 11, 2018, 9:51pm UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102/2 "2018-01-11T21:51:27Z")
You wouldn’t happen to be listing one of your lambda functions under the `resources` section would you? Something like this: ``` resources: Resources: lambdaFnName: Type: AWS::Lambda::Function Properties: ... ``` It appears that if you add a lambda under the `resources` section, the `Code` field is required and the error handling for a missing `Code` field is pretty poor (as in non-existent). ---
**Author:** ![brettcooper](https://avatars.discourse-cdn.com/v4/letter/b/e480ec/32.png) [@brettcooper](https://forum.serverless.com/u/brettcooper)\ **Post date:** [May 30, 2018, 3:34pm UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102/3 "2018-05-30T15:34:20Z")
I encountered the same issue and it was because the case of the function name was off in the resources section. I renamed the lambda function name in the resources section to match the lambda function name exactly from .serverless/cloudformation-template-update-stack.json and the S3Key error went away. ---
**Author:** ![imrajdas](https://avatars.discourse-cdn.com/v4/letter/i/ed655f/32.png) [@imrajdas](https://forum.serverless.com/u/imrajdas)\ **Post date:** [August 7, 2018, 5:53pm UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102/4 "2018-08-07T17:53:36Z")
I think you forgot to add **Code** field in lambda function resource > resources: > Resources: > offlineStatemenFunction: > Type: AWS::Lambda::Function > Properties: > **Code: #actual code, which echos the incoming event** > ZipFile: \> > exports.handler = function(event, context, callback) { > console.log(“receiving event”); > console.log(event); > callback(null,“done”); > }; > Handler: index.handler > Role: > Fn::GetAtt: [LambdaRole , ARN] > Runtime: nodejs8.10 > Timeout: 300 > [/quote] ---
**Author:** ![kalinchernev](https://yyz2.discourse-cdn.com/flex036/user_avatar/forum.serverless.com/kalinchernev/32/1041_2.png) [@kalinchernev](https://forum.serverless.com/u/kalinchernev)\ **Post date:** [October 19, 2018, 7:42am UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102/5 "2018-10-19T07:42:04Z")
The issue comes from the fact that sometimes there is a difference between how you name the function in your `serverless.yaml` file and how the framework actually names it during its creation in CloudFormation. For instance, I named a function `onObjectCreated` in the configuration file, whereas it became `OnObjectCreatedLambdaFunction` in CloudFormation. You can see this inspecting the list of created `Resources` in the console of the service. ---
**Author:** ![Aljaz-S](https://avatars.discourse-cdn.com/v4/letter/a/e9bcb4/32.png) [@Aljaz-S](https://forum.serverless.com/u/Aljaz-S)\ **Post date:** [February 25, 2020, 12:32pm UTC](https://forum.serverless.com/t/cannot-set-property-s3key-of-undefined/3102/6 "2020-02-25T12:32:14Z")
Hi, I am having same problem at the moment when I am trying to deploy from one AWS account to another. Would it be possible to provide your serverless.yaml file ? At the moment I am not sure if the issue is with function name as it is mentioned in this topic or something else. Thanks in advance. Br, Aljaž.