node-urclient

This repository is part of the Joyent Triton project. See the contribution guidelines and general documentation at the main Triton project page.

A high-level client for the use of the ur agent in Joyent Triton DataCenter. The client allows the consumer to discover compute nodes (servers) in a Triton DataCenter deployment, copy files to and from those nodes, ping nodes, and run arbitrary commands.

Overview

This library provides two classes:

• URClient, a client for performing node discovery and interacting with the ur-agent of a single node, via AMQP, for the purpose of running a command or transferring a file.
• RunQueue, a higher-level orchestration class, capable of performing the same action on an incrementally specified set of remote ur-agent instances, with per-node execution timeouts and starting line synchronisation

The software is basically done, but the documentation is still a work in progress.

URClient; Interacting With A Single Node

discover(); Node Discovery

Create an instance of URClient, thus:

var mod_urclient = require('urclient');

URCLIENT = mod_urclient.create_ur_client({
    log: LOG,
    connect_timeout: 5000,
    enable_http: false,
    bind_ip: '10.0.0.1',
    amqp_config: {
        login: 'guest',
        password: 'guest',
        host: '10.0.0.100',
        port: 5672
    }
});

URCLIENT.on('ready', function () {
    var disco = URCLIENT.discover({
        timeout: 3 * 1000,
        exclude_headnode: false
    });

    disco.on('server', function (server) {
        console.log('found server: %s (%s)', server.uuid, server.hostname);
    });
    disco.on('end', function () {
        console.log('discovery complete');
        process.exit(0);
    });
});

The discover() function returns an event emitter that will emit 'server' events for each server that responds to the discovery request. If the same server responds more than once, only the first response will induce a 'server' event. Once the discovery timeout has expired, an 'end' event will be emitted.

If you need to check for the existence of a specific set of hostnames or UUIDs, provide that list to discover() in the node_list parameter. In this mode, the 'end' event will trigger when all nodes are discovered. An 'error' will be generated in the event that we were not able to find a match for each node in node_list, or if a problem arises with the underlying AMQP transport.

ping(); Ping A Node

TODO: Not Yet Documented

exec(); Execute Script On Node

TODO: Not Yet Documented

send_file(); Send File To Node

TODO: Not Yet Documented

recv_file(); Receive File From Node

TODO: Not Yet Documented

RunQueue; Interacting With A Set Of Nodes

add_server(); Add Node To Set

TODO: Not Yet Documented

start(); Begin Execution On Nodes In Set

You may call start() at any time -- before or after selecting nodes, and before calling close() to finish node selection. This enables you to either configure the entire set in advance and only execute once you have finished discovery, or begin executing immediately as discovery messages are still arriving.

close(); Finish Specifying Set

TODO: Not Yet Documented

'dispatch' event

TODO: Not Yet Documented

'success' event

TODO: Not Yet Documented

'failure' event

TODO: Not Yet Documented

'end' event

TODO: Not Yet Documented

License

This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. For the full license text see LICENSE, or http://mozilla.org/MPL/2.0/.

Copyright 2016 Joyent, Inc.