feat(18-01): add gosnmp dependency, SNMP types, and client builder

- Install gosnmp v1.43.2 as direct dependency - Create snmp package with SNMPConfig, CompiledProfile, PollGroup types - Implement BuildSNMPClient for v1, v2c, and v3 (all security levels) - Map auth protocols (MD5, SHA, SHA224-512) and priv protocols (DES, AES128-256) - MaxRepetitions set to 10 (not gosnmp default 50) for embedded devices - Full test coverage: 9 tests covering all SNMP versions and protocol mappings Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-21 19:18:37 -05:00
parent a231b18d69
commit 9458dadc90
5 changed files with 372 additions and 0 deletions
--- a/poller/internal/snmp/client_test.go
+++ b/poller/internal/snmp/client_test.go
@@ -0,0 +1,200 @@
+package snmp
+
+import (
+	"testing"
+
+	"github.com/gosnmp/gosnmp"
+	"github.com/staack/the-other-dude/poller/internal/store"
+	"github.com/staack/the-other-dude/poller/internal/vault"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBuildSNMPClient_V2c(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "10.0.0.1",
+		SNMPPort:  161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:   "v2c",
+		Community: "test-community",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, gosnmp.Version2c, g.Version)
+	assert.Equal(t, "test-community", g.Community)
+	assert.Equal(t, "10.0.0.1", g.Target)
+	assert.Equal(t, uint16(161), g.Port)
+}
+
+func TestBuildSNMPClient_V1(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "192.168.1.1",
+		SNMPPort:  161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:   "v1",
+		Community: "public",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, gosnmp.Version1, g.Version)
+	assert.Equal(t, "public", g.Community)
+}
+
+func TestBuildSNMPClient_V3_AuthPriv(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "10.0.0.2",
+		SNMPPort:  1161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:       "v3",
+		SecurityLevel: "auth_priv",
+		Username:      "admin",
+		AuthProtocol:  "SHA256",
+		AuthPass:      "authpass123",
+		PrivProtocol:  "AES128",
+		PrivPass:      "privpass456",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, gosnmp.Version3, g.Version)
+	assert.Equal(t, gosnmp.UserSecurityModel, g.SecurityModel)
+	assert.Equal(t, gosnmp.AuthPriv, g.MsgFlags)
+	assert.Equal(t, uint16(1161), g.Port)
+
+	usp, ok := g.SecurityParameters.(*gosnmp.UsmSecurityParameters)
+	require.True(t, ok, "SecurityParameters should be *UsmSecurityParameters")
+	assert.Equal(t, "admin", usp.UserName)
+	assert.Equal(t, gosnmp.SHA256, usp.AuthenticationProtocol)
+	assert.Equal(t, "authpass123", usp.AuthenticationPassphrase)
+	assert.Equal(t, gosnmp.AES, usp.PrivacyProtocol)
+	assert.Equal(t, "privpass456", usp.PrivacyPassphrase)
+}
+
+func TestBuildSNMPClient_V3_AuthNoPriv(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "10.0.0.3",
+		SNMPPort:  161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:       "v3",
+		SecurityLevel: "auth_no_priv",
+		Username:      "monitor",
+		AuthProtocol:  "SHA",
+		AuthPass:      "authonly",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, gosnmp.Version3, g.Version)
+	assert.Equal(t, gosnmp.AuthNoPriv, g.MsgFlags)
+
+	usp := g.SecurityParameters.(*gosnmp.UsmSecurityParameters)
+	assert.Equal(t, "monitor", usp.UserName)
+	assert.Equal(t, gosnmp.SHA, usp.AuthenticationProtocol)
+}
+
+func TestBuildSNMPClient_V3_NoAuthNoPriv(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "10.0.0.4",
+		SNMPPort:  161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:       "v3",
+		SecurityLevel: "no_auth_no_priv",
+		Username:      "readonly",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, gosnmp.Version3, g.Version)
+	assert.Equal(t, gosnmp.NoAuthNoPriv, g.MsgFlags)
+
+	usp := g.SecurityParameters.(*gosnmp.UsmSecurityParameters)
+	assert.Equal(t, "readonly", usp.UserName)
+}
+
+func TestMapAuthProto(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected gosnmp.SnmpV3AuthProtocol
+	}{
+		{"MD5", gosnmp.MD5},
+		{"SHA", gosnmp.SHA},
+		{"SHA224", gosnmp.SHA224},
+		{"SHA256", gosnmp.SHA256},
+		{"SHA384", gosnmp.SHA384},
+		{"SHA512", gosnmp.SHA512},
+	}
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			assert.Equal(t, tt.expected, mapAuthProto(tt.input))
+		})
+	}
+}
+
+func TestMapPrivProto(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected gosnmp.SnmpV3PrivProtocol
+	}{
+		{"DES", gosnmp.DES},
+		{"AES128", gosnmp.AES},
+		{"AES192", gosnmp.AES192},
+		{"AES256", gosnmp.AES256},
+	}
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			assert.Equal(t, tt.expected, mapPrivProto(tt.input))
+		})
+	}
+}
+
+func TestBuildSNMPClient_MaxRepetitions(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "10.0.0.1",
+		SNMPPort:  161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:   "v2c",
+		Community: "public",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, uint32(10), g.MaxRepetitions, "MaxRepetitions must be 10, not gosnmp default 50")
+}
+
+func TestBuildSNMPClient_Timeout(t *testing.T) {
+	dev := store.Device{
+		IPAddress: "10.0.0.1",
+		SNMPPort:  161,
+	}
+	cred := &vault.SNMPCredential{
+		Version:   "v2c",
+		Community: "public",
+	}
+	cfg := DefaultSNMPConfig()
+
+	g, err := BuildSNMPClient(dev, cred, cfg)
+	require.NoError(t, err)
+
+	assert.Equal(t, cfg.Timeout, g.Timeout, "Timeout should come from config")
+	assert.Equal(t, cfg.Retries, g.Retries, "Retries should come from config")
+}