From 5886426dac9df5eee7e3d1662791ab09c231833e Mon Sep 17 00:00:00 2001
From: Christoffer Martinsson <cm@cmtec.se>
Date: Mon, 20 Oct 2025 22:41:21 +0200
Subject: [PATCH] Fix service discovery to detect all services regardless of
 state

- Use systemctl list-unit-files and list-units --all to find inactive services
- Parse both outputs to ensure all services are discovered
- Remove special SSH detection logic since sshd is in service filters
- Rename interesting_services to service_name_filters for clarity
- Now detects services in any state: active, inactive, failed, dead, etc.
---
 agent/src/collectors/systemd.rs | 60 +++++++++++++++++++++------------
 1 file changed, 38 insertions(+), 22 deletions(-)

diff --git a/agent/src/collectors/systemd.rs b/agent/src/collectors/systemd.rs
index ca9e4c1..20430c3 100644
--- a/agent/src/collectors/systemd.rs
+++ b/agent/src/collectors/systemd.rs
@@ -111,19 +111,29 @@ impl SystemdCollector {
 
     /// Auto-discover interesting services to monitor
     fn discover_services(&self) -> Result<Vec<String>> {
-        let output = Command::new("systemctl")
-            .arg("list-units")
+        // First get all unit files (includes inactive services)
+        let unit_files_output = Command::new("systemctl")
+            .arg("list-unit-files")
             .arg("--type=service")
-            .arg("--state=running,failed,inactive")
             .arg("--no-pager")
             .arg("--plain")
             .output()?;
 
-        if !output.status.success() {
+        // Then get all loaded units (includes running/failed services)  
+        let units_output = Command::new("systemctl")
+            .arg("list-units")
+            .arg("--type=service")
+            .arg("--all")
+            .arg("--no-pager")
+            .arg("--plain")
+            .output()?;
+
+        if !unit_files_output.status.success() || !units_output.status.success() {
             return Err(anyhow::anyhow!("systemctl command failed"));
         }
 
-        let output_str = String::from_utf8(output.stdout)?;
+        let unit_files_str = String::from_utf8(unit_files_output.stdout)?;
+        let units_str = String::from_utf8(units_output.stdout)?;
         let mut services = Vec::new();
 
         // Skip setup/certificate services that don't need monitoring (from legacy)
@@ -142,7 +152,7 @@ impl SystemdCollector {
         ];
 
         // Define patterns for services we want to monitor (from legacy)
-        let interesting_services = [
+        let service_name_filters = [
             // Web applications
             "gitea",
             "immich",
@@ -183,10 +193,29 @@ impl SystemdCollector {
             "ark",
         ];
 
-        for line in output_str.lines() {
+        // Parse both unit files and loaded units
+        let mut all_service_names = std::collections::HashSet::new();
+        
+        // Parse unit files (includes inactive services)
+        for line in unit_files_str.lines() {
+            let fields: Vec<&str> = line.split_whitespace().collect();
+            if fields.len() >= 2 && fields[0].ends_with(".service") {
+                let service_name = fields[0].trim_end_matches(".service");
+                all_service_names.insert(service_name.to_string());
+            }
+        }
+        
+        // Parse loaded units (includes running/failed services)
+        for line in units_str.lines() {
             let fields: Vec<&str> = line.split_whitespace().collect();
             if fields.len() >= 4 && fields[0].ends_with(".service") {
                 let service_name = fields[0].trim_end_matches(".service");
+                all_service_names.insert(service_name.to_string());
+            }
+        }
+
+        // Now process all discovered services
+        for service_name in &all_service_names {
                 debug!("Processing service: '{}'", service_name);
 
                 // Skip excluded services first
@@ -207,8 +236,8 @@ impl SystemdCollector {
                     continue;
                 }
 
-                // Check if this service matches our interesting patterns
-                for pattern in &interesting_services {
+                // Check if this service matches our filter patterns
+                for pattern in &service_name_filters {
                     if service_name.contains(pattern) || pattern.contains(service_name) {
                         debug!(
                             "INCLUDING service '{}' because it matches pattern '{}'",
@@ -218,21 +247,8 @@ impl SystemdCollector {
                         break;
                     }
                 }
-            }
         }
 
-        // Always include ssh/sshd if present
-        if !services.iter().any(|s| s.contains("ssh")) {
-            for line in output_str.lines() {
-                let fields: Vec<&str> = line.split_whitespace().collect();
-                if fields.len() >= 4 && (fields[0] == "sshd.service" || fields[0] == "ssh.service")
-                {
-                    let service_name = fields[0].trim_end_matches(".service");
-                    services.push(service_name.to_string());
-                    break;
-                }
-            }
-        }
 
         Ok(services)
     }