benfry · October 3, 2024 01:24
diff --git a/usb_detect.py b/usb_detect.py
 #!/usr/bin/env python3

 import json
 import sys


 ''' Quick hack to detect the speed of plugged-in USB devices on macOS,
    then write a simple HTML page with the info and open it in a browser.
    Calls out to the command line system_profiler tool to retrieve the information.

    Was frustrated by needing to visit
     → About This Mac → More Info… → (scroll down to) System Report → Hardware → USB
    whenever trying to figure out whether a device or cable was working as expected.

    Ben Fry (ben at fathom dot info) 2024-09-29
 '''

 # TODO can't find a proper Apple reference for all of these
 #      missing entries for 20 and 40
 #      unsure how dual vs single channel is denoted (i.e. 1x20 vs 2x10, or 1x40 vs 2x20)
 # https://en.wikipedia.org/wiki/USB_communications#Signaling_rate_(transmission_rate)
 SPEEDS = {
    'low_speed': 'Up to 1.5 Mb/s',
    'full_speed': 'Up to 12 Mb/s',
    'high_speed': 'Up to 480 Mb/s',
    'super_speed': 'Up to 5 Gb/sec',
    'super_speed_plus': 'Up to 10 Gb/s',
 }


 def process_exec(args):
    ''' Simple wrapper on subprocess to just get stdout and stderr.
    '''
    from subprocess import Popen, PIPE
    p = Popen(args, stdout=PIPE, stderr=PIPE)
    (out_data, err_data) = p.communicate()
    result = p.wait()
    return (result, out_data.decode('utf-8'), err_data.decode('utf-8'))


 def decode(blob, found):
    ''' Walk the dictionary recursively to get device entries.
    '''
    for entry in blob:
        if '_items' in entry:
            decode(entry['_items'], found)
        elif 'host_controller' in entry:
            # not personally interested in the hubs
            pass
        else:
            found.append(entry)


 def make_html(found):
    ''' Export an HTML page with 90s-era <table> syntax.
    '''
    outgoing = '''
    <html lang="en-US"><head><meta charset="utf-8"/>

    <head>
        <link href="https://fonts.googleapis.com/css?family=Roboto:400,700" rel="stylesheet">
        <style>html * { font: 14px Roboto; color: #444 }</style>
        <style>a { color: #822 } .less { color: #777 } </style>
    </head>

    <body>
    <table style="margin-left: auto; margin-right: auto;" cellpadding="4">
    '''

    for item in found:
        if 'device_speed' in item:
            outgoing += f"""<tr>
                <td class="less"> {item.get('manufacturer', '')} </td>
                <td style="font-weight: 700"> {item['_name']} </td>
                <td> {SPEEDS.get(item['device_speed'], '')} </td>
                <td> <tt class="less">{item['device_speed']}</tt> </td>
            """

            if 'bus_power' in item:
                outgoing += '<td>'
                bus_power = int(item['bus_power'])
                if 'bus_power_used' in item:
                    bus_power_used = int(item['bus_power_used'])
                else:
                    # bus_power_used = bus_power
                    print('bus power used not present for ' + item['_name'])
                    exit(1)

                width_max = 180  # 180px is probably a good width
                divisor = 900 // width_max  # 900 is gonna be the max mA
                bus_power_px = bus_power // divisor
                bus_power_used_px = bus_power_used // divisor
                remainder_px = bus_power_px - bus_power_used_px

                outgoing += f'<div style="background-color: #822; height: 11px; display: inline-block; width: {bus_power_used_px}px"> </div>'
                outgoing += f'<div style="background-color: #b77; height: 11px; display: inline-block; width: {remainder_px}px"> </div>'

                outgoing += f'<span class="less"> {item["bus_power_used"]} mA </span'

                outgoing += '</td>'

            outgoing += '</tr>'
        else:
            print(f"Skipping {item['_name']} because no speed listed.")

    outgoing += '''
    </table>
    </body>
    </html>
    '''

    return outgoing


 def write_temp(found):
    ''' Write the HTML to the temp folder so it's just cleaned up later.
    '''
    import os
    import tempfile

    fd, path = tempfile.mkstemp(suffix='.html')
    try:
        with os.fdopen(fd, 'w') as tmp:
            # do stuff with temp file
            tmp.write(make_html(found))
            process_exec(['open', path])
    except Exception as e:
        print(e)
    finally:
        # os.remove(path)
        pass


 if __name__ == "__main__":
    (result, out, err) = process_exec([
        'system_profiler',
        '-json',
        '-detailLevel', 'full',
        'SPUSBDataType'
    ])
    if len(err.strip()) > 0:
        print(err, file=sys.stderr)
    if result == 0:
        found = [ ]
        decode(json.loads(out)['SPUSBDataType'], found)
        write_temp(found)

    exit(result)
	#!/usr/bin/env python3

	import json
	import sys


	''' Quick hack to detect the speed of plugged-in USB devices on macOS,
	then write a simple HTML page with the info and open it in a browser.
	Calls out to the command line system_profiler tool to retrieve the information.

	Was frustrated by needing to visit
	 → About This Mac → More Info… → (scroll down to) System Report → Hardware → USB
	whenever trying to figure out whether a device or cable was working as expected.

	Ben Fry (ben at fathom dot info) 2024-09-29
	'''

	# TODO can't find a proper Apple reference for all of these
	# missing entries for 20 and 40
	# unsure how dual vs single channel is denoted (i.e. 1x20 vs 2x10, or 1x40 vs 2x20)
	# https://en.wikipedia.org/wiki/USB_communications#Signaling_rate_(transmission_rate)
	SPEEDS = {
	'low_speed': 'Up to 1.5 Mb/s',
	'full_speed': 'Up to 12 Mb/s',
	'high_speed': 'Up to 480 Mb/s',
	'super_speed': 'Up to 5 Gb/sec',
	'super_speed_plus': 'Up to 10 Gb/s',
	}


	def process_exec(args):
	''' Simple wrapper on subprocess to just get stdout and stderr.
	'''
	from subprocess import Popen, PIPE
	p = Popen(args, stdout=PIPE, stderr=PIPE)
	(out_data, err_data) = p.communicate()
	result = p.wait()
	return (result, out_data.decode('utf-8'), err_data.decode('utf-8'))


	def decode(blob, found):
	''' Walk the dictionary recursively to get device entries.
	'''
	for entry in blob:
	if '_items' in entry:
	decode(entry['_items'], found)
	elif 'host_controller' in entry:
	# not personally interested in the hubs
	pass
	else:
	found.append(entry)


	def make_html(found):
	''' Export an HTML page with 90s-era <table> syntax.
	'''
	outgoing = '''
	<html lang="en-US"><head><meta charset="utf-8"/>

	<head>
	<link href="https://fonts.googleapis.com/css?family=Roboto:400,700" rel="stylesheet">
	<style>html * { font: 14px Roboto; color: #444 }</style>
	<style>a { color: #822 } .less { color: #777 } </style>
	</head>

	<body>
	<table style="margin-left: auto; margin-right: auto;" cellpadding="4">
	'''

	for item in found:
	if 'device_speed' in item:
	outgoing += f"""<tr>
	<td class="less"> {item.get('manufacturer', '')} </td>
	<td style="font-weight: 700"> {item['_name']} </td>
	<td> {SPEEDS.get(item['device_speed'], '')} </td>
	<td> <tt class="less">{item['device_speed']}</tt> </td>
	"""

	if 'bus_power' in item:
	outgoing += '<td>'
	bus_power = int(item['bus_power'])
	if 'bus_power_used' in item:
	bus_power_used = int(item['bus_power_used'])
	else:
	# bus_power_used = bus_power
	print('bus power used not present for ' + item['_name'])
	exit(1)

	width_max = 180 # 180px is probably a good width
	divisor = 900 // width_max # 900 is gonna be the max mA
	bus_power_px = bus_power // divisor
	bus_power_used_px = bus_power_used // divisor
	remainder_px = bus_power_px - bus_power_used_px

	outgoing += f'<div style="background-color: #822; height: 11px; display: inline-block; width: {bus_power_used_px}px"> </div>'
	outgoing += f'<div style="background-color: #b77; height: 11px; display: inline-block; width: {remainder_px}px"> </div>'

	outgoing += f'<span class="less"> {item["bus_power_used"]} mA </span'

	outgoing += '</td>'

	outgoing += '</tr>'
	else:
	print(f"Skipping {item['_name']} because no speed listed.")

	outgoing += '''
	</table>
	</body>
	</html>
	'''

	return outgoing


	def write_temp(found):
	''' Write the HTML to the temp folder so it's just cleaned up later.
	'''
	import os
	import tempfile

	fd, path = tempfile.mkstemp(suffix='.html')
	try:
	with os.fdopen(fd, 'w') as tmp:
	# do stuff with temp file
	tmp.write(make_html(found))
	process_exec(['open', path])
	except Exception as e:
	print(e)
	finally:
	# os.remove(path)
	pass


	if __name__ == "__main__":
	(result, out, err) = process_exec([
	'system_profiler',
	'-json',
	'-detailLevel', 'full',
	'SPUSBDataType'
	])
	if len(err.strip()) > 0:
	print(err, file=sys.stderr)
	if result == 0:
	found = [ ]
	decode(json.loads(out)['SPUSBDataType'], found)
	write_temp(found)

	exit(result)