windows_exporter/internal/collector/process/AGENTS.md

process collector

IIS application pool names (--collector.process.iis) come from two sources.

• Primary: the -ap "<pool>" argument of each w3wp command line, read with NtQueryInformationProcess(ProcessCommandLineInformation). It needs only PROCESS_QUERY_LIMITED_INFORMATION and Windows 8.1 or Server 2012 R2.
• Fallback: WorkerProcess in root\WebAdministration, used only when it answered during Build and a command line can't be read or has no -ap. It needs the optional IIS Management Scripts and Tools feature (Web-Scripting-Tools), and asks WAS through RSCA on every query.
• splitCommandLine follows CommandLineToArgvW. FuzzSplitCommandLine compares it with windows.DecomposeCommandLine; run it after parser changes with go test -run '^$' -fuzz FuzzSplitCommandLine ./internal/collector/process/.
• Without IIS, TestCollectorWorkerProcessCommandLine starts a suspended copy of the test binary named w3wp.exe to check the published label. The IIS tests compare against WMI when available and against the IIS APPPOOL\<pool> process owner.
• Don't create or change IIS application pools on a development machine to test edge cases; use suspended processes with crafted command lines.