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JavaScript Build a Simple Dynamic Site with Node.js HTTP Methods and Headers Dealing with the POST Body

postbody? where is that coming from?

sorry I didn't see the variable defined..

1 Answer

Sam Hall
PLUS
Sam Hall
Courses Plus Student 8,636 Points

Hi Thomas,

I'm learning as I go here, but this is what I understand is happening:

When the POST request is received it fires a "data" event.

We are attaching an event listener to this, so that a callback function executes when the post request data is received:

request.on("data", function(postBody){
   console.log(postBody);
});

So, when the server has received the POST request, it will trigger the callback function. By default the data event always passes a parameter into the function: the chunk of data that has been received.

postBody is the simply the name that Andrew has chosen to use for the chunk of data that is passed into the callback function when the "data" event is triggered. It's the name we use to reference it if we want to log it to the console, convert it to a string, etc.

The variable doesn't need to be defined because it is sent by the "data" event.

Hope that helps.

Sam