sse

README

xk6-sse

A k6 extension for Server-Sent Events (SSE) using the xk6 system.

See the K6 SSE Extension design.

k6 version

This extension is tested with k6 version v0.53.0 last release is v0.1.3.

Build

To build a k6 binary with this plugin, first ensure you have the prerequisites:

• Go toolchain
• Git

Then:

1. Install xk6:

go install go.k6.io/xk6/cmd/xk6@latest

1. Build the binary:

xk6 build master \
--with github.com/phymbert/xk6-sse

Example

import sse from "k6/x/sse"
import {check} from "k6"

export default function () {
    const url = "https://echo.websocket.org/.sse"
    const params = {
        method: 'GET',
        headers: {
            "Authorization": "Bearer XXXX"
        },
        tags: {"my_k6s_tag": "hello sse"}
    }

    const response = sse.open(url, params, function (client) {
        client.on('open', function open() {
            console.log('connected')
        })

        client.on('event', function (event) {
            console.log(`event id=${event.id}, name=${event.name}, data=${event.data}`)
            if (parseInt(event.id) === 4) {
                client.close()
            }
        })

        client.on('error', function (e) {
            console.log('An unexpected error occurred: ', e.error())
        })
    })

    check(response, {"status is 200": (r) => r && r.status === 200})
}

License

                             Apache License
                       Version 2.0, January 2004
                    http://www.apache.org/licenses/

Documentation

Overview

Package sse implements a k6/x/sse javascript module extension for k6. It provides basic functionality to handle Server-Sent Event over http that *blocks* the event loop while the http connection is opened. [SSE API design document]: https://github.com/phymbert/xk6-sse/blob/master/docs/design/021-sse-api.md#proposed-solution

Index

• Constants
• Variables
• type Client
  • func (c *Client) Close() error
  • func (c *Client) On(event string, handler sobek.Value)
• type Event
• type HTTPResponse
• type RootModule
  • func New() *RootModule
  • func (*RootModule) NewModuleInstance(m modules.VU) modules.Instance

Constants

const MetricEventName = "sse_event"

MetricEventName is the sse event metric of the module

Variables

var ErrSSEInInitContext = common.NewInitContextError("using sse in the init context is not supported")

ErrSSEInInitContext is returned when sse are using in the init context

Types

type Client

type Client struct {
	// contains filtered or unexported fields
}

Client is the representation of the sse returned to the js.

func (*Client) Close

func (c *Client) Close() error

Close the event loop

func (*Client) On

func (c *Client) On(event string, handler sobek.Value)

On is used to configure what the client should do on each event.

type Event

type Event struct {
	ID      string
	Comment string
	Name    string
	Data    string
}

Event represents a Server-Sent Event

type HTTPResponse

type HTTPResponse struct {
	URL     string            `json:"url"`
	Status  int               `json:"status"`
	Headers map[string]string `json:"headers"`
	Error   string            `json:"error"`
}

HTTPResponse is the http response returned by sse.open.

type RootModule

type RootModule struct{}

RootModule is the global module instance that will create module instances for each VU.

func New

func New() *RootModule

New returns a pointer to a new RootModule instance.

func (*RootModule) NewModuleInstance

func (*RootModule) NewModuleInstance(m modules.VU) modules.Instance

NewModuleInstance implements the modules.Module interface to return a new instance for each VU.