Espruino Host

Tool to run in the background and provide a WebSocket server that http://espruino.com/ide can use to access BLE and Serial devices.

Usage

• Run the tool for your platform in the builds folder
• Go to https://espruino.github.io/EspruinoWebIDE/
• In settings (top right), Communications, ensure Websocket URL is set to the URL reported in the tool (probably wss://localhost:31234)
• MacOS Note: If you're prompted for a keychain password in the next step, you do need to enter one. Do not close/cancel the window or you will have to restart your Mac before you'll be able to get Espruino Host working!
• Instead of wss://localhost:31234, go to https://localhost:31234 in your browser, and if prompted by a security warning click 'advanced' and then 'ignore' (or follow the Setup SSL Certificate heading below). A page seting 'Empty Response' is fine.
• Now connect on the Web IDE page you first opened, and you're sorted!

Setup SSL Certificate

To avoid the issues around permissions, you can pre-install the certificate:

• Go to Chrome Settings
• Scroll down & click Advanced
• Manage Certificates
  • Linux -> IMPORT
  • Mac OS -> File -> Import Items...
• Choose localhost.p12 with password espruino

Creating your own key/certificate

EspruinoHub uses a built-in certificate, but you can:

Create with:

openssl req -newkey rsa:2048 -nodes -keyout localhost.key -x509 -out localhost.cert
# Then edit the app.qrc file in Qt Creator and update
# the localhost.* files

Turn the certificate into something that can be loaded by most web browsers with:

openssl pkcs12 -export -clcerts -in localhost.cert -inkey localhost.key -out localhost.p12

Protocol

• -> means sent to EspruinoHost
• <- means returned from EspruinoHost

-> {"type":"version"}

<- {
    "type": "version",
    "version": "0.1"
}

List available ports

-> {"type":"list"}

<- {
    "ports": [
        {
            "description": "STM32 Virtual ComPort",
            "path": "/dev/ttyACM0",
            "interface": "serial"
        },
        {
            "description": "",
            "path": "/dev/ttyS0",
            "interface": "serial"
        }
    ],
    "type": "list"
}

Connect to a port

-> {"type":"connect","interface":"serial","path":"/dev/ttyACM0","baud":9600}
-> {"type":"connect","interface":"bluetooth","path":"C1:6F:4D:4A:C1:27"}

<- {"type":"connect"}
or
<- {"type":"error", "message":""}

Write data

-> {"type":"write","data":"\u0003"}
-> {"type":"write","data":"LED.set()\r\n"}

// when write complete...
<- {"type":"write",count:234}

Data received from remote device

<- {"type":"read","data":" ... "}

To disconnect

-> {"type":"disconnect"}

Building

LINUX

You need to install these dependencies before installing Qt and building or Bluetooth will silently fall back to a dummy version

sudo apt-get install libbluetooth-dev bluetooth blueman bluez libusb-dev libdbus-1-dev bluez-hcidump bluez-tools

Windows

You'll need to build against Visual Studio 64 bit, or Bluetooth support won't work!

TODO

• Send 'status' messages during BLE connect to avoid the multi-second second pause during connection
• Deal with BLE connection errors properly (probably not handled right at the moment)
• QSettings to store persistent settings
• Ability to access local files within some predefined directory - for modules/etc
• Have option to download IDE locally (as a zip?), then serve the whole thing up over the WebSocket URL