This is a Node.js and browser library for consuming Greyhound data.

npm install greyhound.js

The library provides two classes named GreyhoundReader and Schema.

This is the main class to read data from Greyhound. You start by creating a session on the Greyhound server and then querying it for data.

var GreyhoundReader = require('greyhound.js').GreyhoundReader

var reader = GreyhoundReader("server.com");
reader.createSession("pipeline-id", function(err, sessionId) {
    if (err) return console.log("Error creating pipeline:", err);
    console.log("Created a new session with id:", sessionId);
});

Once you have a session you can start reading data from it, right now the reader supports reading all of the data in one go.

reader.read(sessionId, function(err, data) {
    if (err) return console.log("Failed to read:", err);
    console.log("Got", data.length, "total bytes");
});

You can additionally specify a schema as well:

var Schema = require('greyhound.js').Schema;

reader.read(sessionId, {
    schema: Schema.standard()
}, function(err, data) {
    if (err) return console.log("Failed to read:", err);
    console.log("Got", data.length, "total bytes");
});

You should finally destroy the session:

reader.destroy(sessionId, function(err) {
    if (err) return console.log("Failed to destroy session:", err);
    console.log("Session was destroyed");
});

A Schema class is provided to construct schemas on the fly. This class provides two standard schemas accessible through functions: standard() and XYZ(). To construct a schema you could use one of these as starting points or build your own.

As an example, a schema definition for just the X value, along with Intensity and Red color channel would look like:

Schema.X().Intensity().Red();

These fields have default types, but you can always specify your own:

Schema.X("floating", 8).Intensity("unsigned", 2).Red("float", 4);

Just checkout the code and run

gulp tdd

This will give you URL which you can visit to see the output of unit-tests. Additionally,

npm test

will run the test suite for node.js.

MIT