CSS Classes: connected (in combination with wireless, wired, mobile, other or local), disconnected, or portal (in combination with same as connected)

waybar.json

{
  "custom/network": {
    "exec": "~/.scripts/waybar/network",
    "return-type": "json",
    "interval": 5,
    "format": " {icon} {}",
    "tooltip": true,
    "format-icons": {
        "disconnected": "",
        "wired": "",
        "wireless": "",
        "mobile": ""
    }
}
}

waybar_network.rb

#!/usr/bin/env ruby

require 'json'
require 'yaml'

KIBI = 1024
MEBI = KIBI * 1024
GIBI = MEBI * 1024

# kind can be (:wired, :wireless, :mobile, :local, :other)
NetworkInterface = Struct.new(:name, :kind, :address, :lldp, :link_state, :display_name, :bwinfo)
LLDPInfo = Struct.new(:device, :port, :vlan)
# Internet can be either of :connected (everything working), :disconnected (link down), :portal (captive portal)
NetworkData = Struct.new(:default_device, :internet, :data)
BWInfo = Struct.new(:out, :in)

def get_default_iface()
    output = `ip -j r g 0.0.0.1`
    if output.chomp.empty?
        nil
    else
        JSON.parse(output).first['dev']
    end
end

def get_ifaces(state)
    ifaces = JSON.parse(`ip -j a s`)
    #routes = JSON.parse(`ip -j r s`)
    lldp = JSON.parse(`lldpctl -f json`)["lldp"]["interface"] || {}

    passed_time = Time.now.to_f - state[:timestamp]

    data = ifaces.map do |iface|
        ifname = iface['ifname']
        bytes_tx = File.read("/sys/class/net/#{ifname}/statistics/tx_bytes").to_i
        bytes_rx = File.read("/sys/class/net/#{ifname}/statistics/rx_bytes").to_i

        bw_info = if state[:iface][ifname]
            speed_tx = (bytes_tx - state[:iface][ifname][:last_tx]) / passed_time
            speed_rx = (bytes_rx - state[:iface][ifname][:last_rx]) / passed_time
            BWInfo.new(speed_tx, speed_rx)
        end

        kind = case ifname
            when 'lo' then :local
            when /^(eth\d+$|en[\d\w]+)$/ then :wired
            when /^(wlan\d+|wl[\d\w]+)$/ then :wireless
            when /^ww[\d\w]+$/ then :mobile # TODO: Determine signal strength
            else 
                :other
        end
        display_name = case kind
            when :local then "local network"
            when :wireless then `iwgetid -r`.chomp
            # TODO: Retrieve Carrier information for mobile networks
        end
        addrs = iface['addr_info'].map { |addr| "#{addr['local']}/#{addr['prefixlen']}" }
        
        lldp_data = lldp.first
        lldp_info = if lldp_data
            iface_lldp = lldp_data[ifname]
            lldp_info = if iface_lldp 
                dev_name = iface_lldp["chassis"].keys.first
                port_name = iface_lldp["port"]["id"]["value"]
                vlan_name = if iface_lldp["vlan"]
                    iface_lldp["vlan"]["vlan-id"]
                end
                LLDPInfo.new(dev_name, port_name, vlan_name)
            end
        end

        state[:iface][ifname] = { last_tx: bytes_tx, last_rx: bytes_rx }

        NetworkInterface.new(iface['ifname'], kind, addrs, lldp_info, iface['operstate'].downcase.to_sym, display_name, bw_info)
    end
    state[:timestamp] = Time.now.to_f
    data
end

def filter_data(data, config)
    data.select do |iface|
        config["iface_whitelist"].any?{|we| iface.name =~ Regexp.new(we)}||
            !config["iface_blacklist"].all?{|be| iface.name =~ Regexp.new(be)}
    end.sort_by { |iface| iface.link_state == :up ? 0 : 1 }
end

def network_name()
    res = File.read("/etc/resolv.conf").lines
        .map { |line| line.chomp.split(' ') }
        .find { |line| line[0] == 'domain' }
    return res[1] if res
    res = File.read("/etc/resolv.conf").lines
        .map { |line| line.chomp.split(' ') }
        .find { |line| line[0] == 'search' }
    res[1] if res
end

def render_speed(value)
    value = value * 8
    if value < KIBI
        "%.2f" % value + "bit/s"
    elsif value < MEBI
        "%.2f" % (value / KIBI) + "kbit/s"
    elsif value < GIBI
        "%.2f" % (value / MEBI) + "Mbit/s"
    else
        "%.2f" % (value / GIBI) + "Gbit/s"
    end
end

def display_net_info(iface)
    color = iface.link_state == :down ? '#ff0000' : '#00ff00'
    ret = ""
    if iface.display_name
        ret << "<span color=\"#{color}\">#{iface.display_name}</span> (#{iface.name})"
    else
        ret << "<span color=\"#{color}\">" << iface.name << "</span>"
    end
    if iface.link_state == :down
        ret << ": DOWN"
    else
        ret << "\n #{render_speed(iface.bwinfo.out)}  #{render_speed(iface.bwinfo.in)}"
        if iface.lldp
            ret << "\nLLDP: [#{iface.lldp.device}] #{iface.lldp.port}"
            ret << " | VLAN " << iface.lldp.vlan if iface.lldp.vlan
        end
        ret << iface.address.map { |addr| "\n  <span color=\"#0000ff\">" + addr + '</span>'}.join
    end
end

def class_from_default(default, portal)
    if default
        if portal
            "portal"
        else
            ["connected", default.kind.to_s]
        end
    else
        "disconnected"
    end
end

def alt_from_default(default, portal)
    if default
        default.kind.to_s
    else
        "disconnected"
    end
end

def display_from_default(default)
    return 'Disconnected' if default.nil?
    ret = default.display_name || network_name()
    ret = default.name + ": " + default.address.first unless ret
    ret = default.name unless ret
    ret
end

def display_data(data, default)
    default_iface = data.find { |iface| iface.name == default }
    portal = nil
    net_name = display_from_default(default_iface)
    {
        text: net_name,
        tooltip: data.map {|iface| display_net_info(iface) }.join("\n\n"),
        class: class_from_default(default_iface, portal),
        alt: alt_from_default(default_iface, portal)
    }.to_json
end

config = YAML.load_file(File.expand_path("~/.config/waybar_network.yml"))

state = if File.exists?("/tmp/bwstate")
    YAML.load_file("/tmp/bwstate")
else
    { timestamp: 0, iface: {} }
end

ifaces = get_ifaces(state)
default = get_default_iface()
ifaces = filter_data(ifaces, config)
puts display_data(ifaces, default)

File.write("/tmp/bwstate", state.to_yaml)

waybar_network.yml

iface_whitelist:
  - "^en[\\d\\w]+$"
  - "^eth\\d+$"
  - "^wl[\\d\\w]+$"
  - "^wlan\\d+$"
  - "^ww[\\d\\w]+$"

iface_blacklist: []