I recently updated to the latest version of Node.js (1.10~) from 0.8~, and I've been getting a message when running that says:

   util.pump() is deprecated. Use readableStream.pipe() instead.

I've tried to switch my functions to say readableStream.pipe(), but I don't think it's working the same.

So I have three questions:

1. Why is util.pump deprecated?
2. How do I switch to readableStream.pipe()? OR 3. How do I turn off this warning?

Here is the code where I'm using it (with mustache)

   var stream = mupileAndRender(template_file, json_object_from_db);
       util.pump(stream, res);

When I replace util.pump with readableStream.pipe, I get this error:

ReferenceError: readableStream is not defined

Can anyone help point me in the right direction?

I recently updated to the latest version of Node.js (1.10~) from 0.8~, and I've been getting a message when running that says:

   util.pump() is deprecated. Use readableStream.pipe() instead.

I've tried to switch my functions to say readableStream.pipe(), but I don't think it's working the same.

So I have three questions:

1. Why is util.pump deprecated?
2. How do I switch to readableStream.pipe()? OR 3. How do I turn off this warning?

Here is the code where I'm using it (with mustache)

   var stream = mu.pileAndRender(template_file, json_object_from_db);
       util.pump(stream, res);

When I replace util.pump with readableStream.pipe, I get this error:

ReferenceError: readableStream is not defined

Can anyone help point me in the right direction?

• javascript
• node.js
• mustache

3 Answers 3

Okay, so this question was a pretty easy answer after some more experimentation (though documentation was null).

Basically, readableStream is just a variable you're supposed to replace with your stream. So in my case, the answer is:

stream.pipe(res);

You just replace util, basically, with the stream. Easy peezy.

I Think the following link will help for your work ! https://groups.google./forum/#!msg/nodejs/YWQ1sRoXOdI/3vDqoTazbQQJ

var readS = fs.createReadStream("fileA.txt");
var writeS = fs.createWriteStream("fileB.txt");
util.pump(readS, writeS, function(error)
   // Operation done
}); 

=====>

var readS = fs.createReadStream("fileA.txt");
var writeS = fs.createWriteStream("fileB.txt");
readS.pipe(writeS);

readS.on("end", function() {
   // Operation done
});

You can look this link http://nodejs.cn/api/stream.html
This is emitted whenever the stream.pipe() method is called on a readable stream, adding this writable to its set of destinations.

var writer = getWritableStreamSomehow();
var reader = getReadableStreamSomehow();
writer.on('pipe', (src) => {
console.error('something is piping into the writer');
assert.equal(src, reader);
});
reader.pipe(writer);