About
Binary Data
Overview
Convert String to ArrayBuffer
Convert ArrayBuffer to String
Convert ArrayBuffers to String
Handle Errors Converting ArrayBuffer to String
Immutable ArrayBuffers
Resize an ArrayBuffer
Combine ArrayBuffers
Convert Base64 to Binary Data
Convert Binary Data to Base64
Convert Binary Data to Hex
Convert Hex to Binary Data
Calculate CRC for Binary Data
Compress Binary Data – One Buffer
Compress Binary Data – Streaming
Decompress Binary Data – One Buffer
Decompress Binary Data – Streaming
Captive Portal
Overview
Create Captive Portal
Close Captive Portal
Provide Web Pages for Captive Portal
Get Information from Captive Portal
DNS
Overview
Resolve Name
Resolve Multiple Names
DNS Service Discovery
Overview
Claim Local Name
Advertise Services
Discover Services
EventSource
Overview
Connect
Connect Securely
Close
Receive
Connection Information
Files
Overview
Create, Open, and Close File
Read File
Write File
Delete File
Get File Information
Create Directory
Enumerate Directory
Delete Directory
Open Directory
HTTP
Overview
Make Request using fetch()
Make Secure Request using fetch()
Send Request Headers using fetch()
Receive Response Headers using fetch()
Send Request Body using fetch()
Make Request using HTTP Client
Make Secure Request using HTTP Client
Send Request Headers using HTTP Client
Receive Response Headers using HTTP Client
Send Request Body using HTTP Client
HTTP Server
Overview
Create Server
Route Request
Respond to Request
Respond to Request with File
Receive Request Body
Receive Request Body to File
Implementing ECMA-419 Modules
Overview
Constructor Sets target
Constructor IO
Constructor Clean-up on Failure
close() and [Symbol.dispose]
Calling Callbacks
Setting Options with configure()
Keep Instance Surface Clean
Key-Value Storage
Overview
Read and Write Values using Web Storage
Delete Keys using Web Storage
Enumerate Keys using Web Storage
Read and Write Values using Key-Value Pair
Change Data Formats using Key-Value Pair
Delete Keys using Key-Value Pair
Enumerate Keys using Key-Value Pair
Logging
Overview
Logging with Console
Logging with trace()
MQTT
Overview
Connect to MQTT Server using MQTT()
Connect Securely to MQTT Server using MQTT()
Close Connection using MQTT()
Publish Message using MQTT()
Subscribe to Topic using MQTT()
Receive Messages using MQTT()
Get Connection Information using MQTT()
Connect to MQTT Server using MQTT Client
Connect Securely to MQTT Server using MQTT Client
Close Connection using MQTT Client
Publish Message using MQTT Client
Subscribe to Topic using MQTT Client
Receive Messages using MQTT Client
Optimizing Embedded JavaScript
Overview
When to Optimize
Know Where to Optimize
Loop through an Array
Iterate Over a String
Build a String
Avoid Copying Buffers
Accessing Properties
Map versus Object
Append to an Array
Operate on Bits
Define Class Methods
Streams
Time
Overview
Get Unix Time
Get Time of Day
Get Date
Get Time Since System Start
Get Microseconds
Set System Date and Time
How Time and Timezone are Initialized
Get Time and Date from Real-Time Clock
Set Real-Time Clock Time
Get Time and Date from Network
Sleep
Time Callbacks
Overview
One-Time Callback
Repeating Callback
Repeating Callback with Initial Delay
Immediate Callback
Reschedule Callback
Cancel Callback
Suspend Callback
Transport Layer Security (TLS)
Overview
Include Public Certificates
Include Private Certificates
Diagnostics
DER and PEM Certificates
WebSocket
Overview
Connect to Server using WebSocket()
Connect Securely to Server using WebSocket()
Close Connection using WebSocket()
Send Message using WebSocket()
Receive Message using WebSocket()
Get Connection Information using WebSocket()
Connect to Server using WebSocket Client
Connect Securely to Server using WebSocket Client
Close Connection using WebSocket Client
Send Message using WebSocket Client
Receive Message using WebSocket Client
Control Messages using WebSocket Client
Connect to Server using WebSocketStream
Connect Securely to Server using WebSocketStream
Close Connection using WebSocketStream
Send Message using WebSocketStream
Receive Message using WebSocketStream
WebSocket Server
Overview
Create WebSocket Server Endpoint
Accept WebSocket Request
Wi-Fi
Overview
Scan for Access Points
Scan Continuously for Access Points
Connect
Reconnect Automatically
Disconnect
Get Connection Information
Use Static IP Address
Wi-Fi Access Point
Overview
Create Access Point
Close Access Point
Get Information
Manage Stations
DNS Redirect
Provide HTTP Server
The WebSocket Server provides comprehensive support for the WebSocket protocol by building on the HTTP Server and WebSocket client capabilities. A WebSocket connection begins with an HTTP connection before transitioning to the WebSocket protocol. This phase is implemented in the HTTP server using the WebSocket Handshake route. Once the handshake is complete, the connection is detached from the HTTP server and attached to a WebSocket client. While this may seem counter-intuitive, once the connection has been established, WebSocket is effectively a peer-to-peer protocol so the same API can be used by both endpoints.
This guide covers the process of creating a WebSocket server endpoint, accepting connections, and attaching them to a WebSocket client. For deeper information see the HTTP Server Guide and WebSocket Guide.
Using ECMA-419 WebSocket Handshake Route
The WebSocket Handshake Route is included by the HTTP Server manifest. Add it to your project's manifest:
$(MODDABLE)/examples/io/listener/httpserver/manifest_httpserver.json
To attach accepted connections to a WebSocket client, add the WebSocket manifest:
$(MODDABLE)/examples/io/tcp/websocket/manifest_websocket.json
This provides both the Web platform's WebSocket() and ECMA-419 WebSocket Client.
If your project accesses the HTTP Server through device.network.http.server, mcpack includes the WebSocket Handshake route automatically.
- Standards
- Examples
- Implementation
- TypeScript Declaration