Function argument in nodejs-CodePudding

Variable when passed through a function returns property of value undefined. I'm passing variable ApiId or ApiName. Should the variable name be wrapped some other way inside the function?

I'm using this

Error:

ERROR   Invoke Error    
{
    "errorType": "TypeError",
    "errorMessage": "Cannot read property 'value' of undefined",
    "stack": [
        "TypeError: Cannot read property 'value' of undefined",
        "    at dimensionValue (/var/task/index.js:20:80)",
        "    at Runtime.exports.handler (/var/task/index.js:37:36)",
        "    at Runtime.handleOnce (/var/runtime/Runtime.js:66:25)"
    ]
}

code:

   function dimensionValue(name) {
       console.log("Testing")
       //var dimensionsValue = sns.Trigger.Dimensions.find(dimension => dimension.name === name).value 
       return sns.Trigger.Dimensions.find(dimension => dimension.name === name).value
   }
   
   
  if (sns.Trigger.Namespace == "AWS/ApiGateway") {
      console.log("Testing2")
    if (sns.Trigger.Dimensions.find(dimension => dimension.name === 'ApiId') && sns.Trigger.Dimensions.find(dimension => dimension.name === 'Stage')) {
        console.log('ApiId and Stage')
        var sns_DimensionsValue = dimensionValue('ApiId')   '_'   dimensionValue('Stage')
    } else if (sns_DimensionsValue == sns.Trigger.Dimensions.find(dimension => dimension.name === 'ApiName') &&  sns.Trigger.Dimensions.find(dimension => dimension.name === 'Stage')) {
        console.log('ApiName and Stage')
        var sns_DimensionsValue =  dimensionValue('ApiName')   '_'    dimensionValue('Stage') 
    } else if (sns_DimensionsValue == sns.Trigger.Dimensions.find(dimension => dimension.name === 'ApiId')) {
        console.log('ApiId')
        var sns_DimensionsValue =  dimensionValue('ApiId')    
    } else if (sns_DimensionsValue == sns.Trigger.Dimensions.find(dimension => dimension.name === 'ApiName')) {
         console.log('ApiName')
        var sns_DimensionsValue =  dimensionValue('ApiName')    
    }
  }

CodePudding user response：

The problem are those sns_DimensionsValue == parts at the start of every condition. Just remove them.

You essentially do if (undefined == findAppId() && findStage()), which will be true if Stage was found and AppId wasn't, but then you attempt to access the value of AppId and fail.

Let me suggest a generally simplified approach:

const dimensions = Object.fromEntries(sns.Trigger.Dimensions.map(d => [d.name, d.value]))
let sns_DimensionsValue = dimensions.ApiId ?? dimensions.ApiName
if (!sns_DimensionsValue) throw new Error('No API ID/API name found')
if (dimensions.Stage) sns_DimensionsValue  = '_'   dimensions.Stage