Odtnhj

i was trying to use Lambda@Edge to handle A/B testing in my site.
i wonder is there a way to let Lambada@Edge functions load an external config data from a url, eg. i created an api to return the traffic rates of A/B channels,i want control that config data outside, so that i can dynamically adjust the traffics flow to A or B channel and no need to modify the Lambda function.
what i did now is

var versions = ;
var isLoadingVersionData = false;
const https = require('https');
function loadVersions() 
if (isLoadingVersionData)
 return null;

isLoadingVersionData=true;

https.get('https://example.com/getAbTestConfig', (res) => 
 res.on('data', (d) => 
 var parsedBody = JSON.parse(d);
 if (parsedBody.status)
 versions = parsedBody.data;

 );

 ).on('error', (e) => 
 console.log(e);
 );


//and load the function in handler
exports.handler = (event, context, callback) => 
 context.callbackWaitsForEmptyEventLoop = false;
 loadVersions();

i wonder this variable "versions" can be loaded correctly and shared in each later requests

do you have some more effectually solutions?

Why not maintain this data in S3 and use your Lambda@Edge to get the configuration from there? Further to reduce latency, you can front the S3 bucket containing traffic ratio with CloudFront and have your L@E make a call to CloudFront and get the desired value.

I was facing the same issue but not for A/B testing. I just created a json file in my lambda function to avoid delay of making http calls inside lambda functions. It works but the maintenance is not good, as every time when I need to change the Json file I need deploy the lambda function again.

While I was searching for it, I found same solution described for Mr.Ocean above, sounds like a good alternative to maintain the data in S3.