From d3ad0f70134c8a8d4957ed68075b26b9909f1de7 Mon Sep 17 00:00:00 2001
From: Jason Staack <jason@staack.com>
Date: Sun, 22 Mar 2026 08:41:35 -0500
Subject: [PATCH] fix(poller): fall back to generic-snmp when device has no
 profile assigned

SNMP devices added without a profile (e.g., via simplified add flow)
were failing with "no SNMP profile assigned". Now falls back to the
generic-snmp profile which collects standard MIB-II metrics.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 poller/internal/snmp/collector.go | 17 ++++++++++++-----
 poller/internal/snmp/profiles.go  |  7 +++++++
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/poller/internal/snmp/collector.go b/poller/internal/snmp/collector.go
index 595c441..07a3b7b 100644
--- a/poller/internal/snmp/collector.go
+++ b/poller/internal/snmp/collector.go
@@ -64,13 +64,20 @@ func NewSNMPCollector(
 func (c *SNMPCollector) Collect(ctx context.Context, dev store.Device, pub *bus.Publisher) error {
 	startTime := time.Now()
 
-	// Step 1: Validate profile.
-	if dev.SNMPProfileID == nil {
-		return fmt.Errorf("device %s: no SNMP profile assigned (SNMPProfileID is nil)", dev.ID)
+	// Step 1: Resolve profile. Fall back to generic-snmp if none assigned.
+	profileID := ""
+	if dev.SNMPProfileID != nil {
+		profileID = *dev.SNMPProfileID
+	} else {
+		profileID = c.profiles.GetGenericID()
+		if profileID == "" {
+			return fmt.Errorf("device %s: no SNMP profile assigned and no generic-snmp fallback found", dev.ID)
+		}
+		slog.Debug("using generic-snmp fallback profile", "device_id", dev.ID)
 	}
-	profile := c.profiles.Get(*dev.SNMPProfileID)
+	profile := c.profiles.Get(profileID)
 	if profile == nil {
-		return fmt.Errorf("device %s: SNMP profile not found for ID %s", dev.ID, *dev.SNMPProfileID)
+		return fmt.Errorf("device %s: SNMP profile not found for ID %s", dev.ID, profileID)
 	}
 
 	// Step 2: Get credentials.
diff --git a/poller/internal/snmp/profiles.go b/poller/internal/snmp/profiles.go
index 0064f75..ddc725c 100644
--- a/poller/internal/snmp/profiles.go
+++ b/poller/internal/snmp/profiles.go
@@ -154,6 +154,13 @@ func (c *ProfileCache) Get(profileID string) *CompiledProfile {
 	return c.profiles[profileID]
 }
 
+// GetGenericID returns the profile ID of the generic-snmp fallback profile.
+func (c *ProfileCache) GetGenericID() string {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.genericID
+}
+
 // MatchSysObjectID finds the best profile for a device's sysObjectID value
 // using longest-prefix matching. Returns the generic-snmp profile ID if
 // no vendor-specific prefix matches.