response-streams v0.1.7

response-streams

Helps to write streams-containing object into non-object stream. The streams packaged with the object will be exhausted.

#Compatibility Compatible with Streams2 & 3. An object treated as Readable stream using duck type checking. That means you can freely use third-party modules such as readable-stream.

For older streams (such as mongoose offers) you can pipe them into newer (likely passing through) streams.

#Installation

npm install response-streams

#Usage Module exposes a function wich takes two args: writable non-object stream and an object to write.

var stream = require('response-streams');
...
stream(dest, obj);

Passed object could itself be a readable stream, or could contain any number of readable streams at any level of nesting.

#Output Generated and written into dest stream data represents valid JSON except for the following cases:

• instead of an object a primitive was passed;
• non-object stream was passed.

Independently of level at which stream is placed, object stream turns into array consisting of objects from that stream whereas non-object stream turns into string consisting of its chunks.

#Backpressure Module respects backpressure.

#Example Lets say we have writable destination stream and two readable streams: one in object mode and other not:

var dest = ...;

var objStream = ...;
var nonObjStream = ...;

We also have written some data into them:

objStream.write({a: 'b'});
objStream.write({c: 'd'});
objStream.end();

nonObjStream.write('x');
nonObjStream.write('y');
nonObjStream.write('z');
nonObjStream.end();

###top-level streams

stream(dest, nonObjStream); // '"xyz"' in dest

or

stream(dest, objStream); // [{"a":"b"},{"c":"d"}] in dest

###deep nesting

var obj = {
  arr: [[], [1,2,3], [[nonObjStream]]],
  obj: {
    subobj: {
      k: objStream
    }
  },
  num: 5,
  bool: true
};

stream(dest, obj);

In dest we get:

{
  "arr": [[],[1,2,3],[["xyz"]]],
  "obj": {
    "subobj": {
      "k": [{"a":"b"},{"c":"d"}]
    }
  },
  "num": 5,
  "bool": true
}