Discover bonjour services
Last modification: Thursday, June 11, 2009 04:07 pmFinds all services of the specified type on the local network and returns their host's name.
Required parameters
Parameter 1 (string)The service type to discover (http://www.dns-sd.org/ServiceTypes.html)
Parameter 2 (float)
The time in seconds the discovery is allowed to take.
Function Calls
-- Find AFP serversdiscoverBonjourServices("afpovertcp", 0.5)
-- Find SSH servers
discoverBonjourServices("ssh", 0.5)
-- Find Macs you could connect to with Server Admin
discoverBonjourServices("servermgr", 0.5)
Implementation
on discoverBonjourServices(_serviceType, _scantime)-- Service types can be looked up at: http://www.dns-sd.org/ServiceTypes.html
script DiscoverBonjourServices_Extras
on sortList(_list)
set _prvDlmt to text item delimiters
set text item delimiters to ASCII character 10
set _string to _list as string
set text item delimiters to _prvDlmt
try
set _sortedString to do shell script "echo " & quoted form of _string & " | sort"
on error
return _list
end try
set _prvDlmt to text item delimiters
set text item delimiters to ASCII character 13
set _sortedList to text items of _sortedString
set text item delimiters to _prvDlmt
return _sortedList
end sortList
on hostnamesFromDiscoveryResults(_results, _serviceType)
set _hostnames to {}
set _prvDlmt to text item delimiters
set text item delimiters to ("_" & _serviceType & "._tcp.")
repeat with _i from 1 to count of _results
try
set _hostname to text item 2 of (item _i of _results)
set end of _hostnames to stripWhitespace(_hostname)
end try
end repeat
set text item delimiters to _prvDlmt
return _hostnames
end hostnamesFromDiscoveryResults
on filterDuplicateString(_strings)
set _uniqueStrings to {}
repeat with _i from 1 to count of _strings
if (item _i of _strings) is not in _uniqueStrings then
set end of _uniqueStrings to (item _i of _strings)
end if
end repeat
return _uniqueStrings
end filterDuplicateString
on stripWhitespace(_string)
set _charCount to count of characters of _string
-- Exit early if there's no string to process
if _charCount is 0 then return ""
-- Determine the first character that is not whitespace
repeat with _startChar from 1 to _charCount
if (ASCII number (character _startChar of _string)) > 32 then exit repeat
end repeat
-- Determine the last characters that is not whitespace
set _endChar to _charCount
repeat
if (ASCII number (character _endChar of _string)) > 32 then exit repeat
set _endChar to _endChar - 1
if _endChar is 0 then exit repeat
end repeat
-- Get the substring
set _prvDlmt to text item delimiters
set text item delimiters to ""
set _string to characters _startChar thru _endChar of _string as string
set text item delimiters to _prvDlmt
return _string
end stripWhitespace
on runDiscoveryScript(_serviceType, _scantime)
try
-- Start the script
set _script to {"#!/bin/bash"}
-- Use the mDNS tool to discover services
set end of _script to "/usr/bin/mDNS -B _" & _serviceType & "._tcp local &"
-- Keep track of the process id for the mDNS tool
set end of _script to "mDNSpid=$!"
-- Wait a little for mDNS to discover services
set end of _script to "sleep " & (_scantime as string)
-- Quit the mDNS tool
set end of _script to "kill -HUP $mDNSpid"
-- Compose the script
set _script to combineList(_script, ASCII character 10)
-- Run the script
set _result to do shell script _script
-- Get the actual results without the header
set _results to paragraphs 4 thru -1 of _result
return _results
on error _eMsg number _eNum
return {}
end try
end runDiscoveryScript
on combineList(_list, _delimiter)
set _prvDlmt to text item delimiters
set text item delimiters to _delimiter
set _list to _list as string
set text item delimiters to _prvDlmt
return _list
end combineList
end script
tell DiscoverBonjourServices_Extras
set _results to runDiscoveryScript(_serviceType, _scantime)
set _hostnames to hostnamesFromDiscoveryResults(_results, _serviceType)
set _hostnames to filterDuplicateString(_hostnames)
set _hostnames to sortList(_hostnames)
end tell
return _hostnames
end discoverBonjourServices
