feat(snmp): add SNMPv3 noAuthNoPriv support with backend test (#6552)

Co-authored-by: dipok-1 <dipokdutta8099@gmail.com>
Co-authored-by: Frank Elsinga <frank@elsinga.de>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

test/backend-test/test-snmp.js

@@ -0,0 +1,128 @@
+const { describe, test } = require("node:test");
+const assert = require("node:assert/strict");
+const { GenericContainer } = require("testcontainers");
+const { SNMPMonitorType } = require("../../server/monitor-types/snmp");
+const { UP } = require("../../src/util");
+const snmp = require("net-snmp");
+
+describe("SNMPMonitorType", () => {
+    test(
+        "check() sets heartbeat to UP when SNMP agent responds",
+        {
+            skip: !!process.env.CI && (process.platform !== "linux" || process.arch !== "x64"),
+        },
+        async () => {
+            const container = await new GenericContainer("polinux/snmpd").withExposedPorts("161/udp").start();
+
+            try {
+                // Get the mapped UDP port
+                const hostPort = container.getMappedPort("161/udp");
+                const hostIp = container.getHost();
+
+                // UDP service small wait to ensure snmpd is ready inside container
+                await new Promise((r) => setTimeout(r, 2000));
+
+                const monitor = {
+                    type: "snmp",
+                    hostname: hostIp,
+                    port: hostPort,
+                    snmpVersion: "2c",
+                    radiusPassword: "public",
+                    snmpOid: "1.3.6.1.2.1.1.1.0",
+                    timeout: 5,
+                    maxretries: 1,
+                    jsonPath: "$",
+                    jsonPathOperator: "!=",
+                    expectedValue: "",
+                };
+
+                const snmpMonitor = new SNMPMonitorType();
+                const heartbeat = {};
+
+                await snmpMonitor.check(monitor, heartbeat);
+
+                assert.strictEqual(heartbeat.status, UP);
+                assert.match(heartbeat.msg, /JSON query passes/);
+            } finally {
+                await container.stop();
+            }
+        }
+    );
+
+    test(
+        "check() throws when SNMP agent does not respond",
+        {
+            skip: !!process.env.CI && (process.platform !== "linux" || process.arch !== "x64"),
+        },
+        async () => {
+            const monitor = {
+                type: "snmp",
+                hostname: "127.0.0.1",
+                port: 65530, // Assuming no SNMP agent is running here
+                snmpVersion: "2c",
+                radiusPassword: "public",
+                snmpOid: "1.3.6.1.2.1.1.1.0",
+                timeout: 1,
+                maxretries: 1,
+            };
+
+            const snmpMonitor = new SNMPMonitorType();
+            const heartbeat = {};
+
+            await assert.rejects(() => snmpMonitor.check(monitor, heartbeat), /timeout|RequestTimedOutError/i);
+        }
+    );
+
+    test("check() uses SNMPv3 noAuthNoPriv session when version is 3", async () => {
+        const originalCreateV3Session = snmp.createV3Session;
+        const originalCreateSession = snmp.createSession;
+
+        let createV3Called = false;
+        let createSessionCalled = false;
+        let receivedOptions = null;
+
+        // Stub createV3Session
+        snmp.createV3Session = function (_host, _username, options) {
+            createV3Called = true;
+            receivedOptions = options;
+
+            return {
+                on: () => {},
+                close: () => {},
+                // Stop execution after session creation to avoid real network I/O.
+                get: (_oids, cb) => cb(new Error("stop test here")),
+            };
+        };
+
+        // Stub createSession
+        snmp.createSession = function () {
+            createSessionCalled = true;
+            return {};
+        };
+
+        const monitor = {
+            type: "snmp",
+            hostname: "127.0.0.1",
+            port: 161,
+            timeout: 5,
+            maxretries: 1,
+            snmpVersion: "3",
+            snmp_v3_username: "testuser",
+            snmpOid: "1.3.6.1.2.1.1.1.0",
+        };
+
+        const snmpMonitor = new SNMPMonitorType();
+        const heartbeat = {};
+
+        await assert.rejects(() => snmpMonitor.check(monitor, heartbeat), /stop test here/);
+
+        // Assertions
+        assert.strictEqual(createV3Called, true);
+        assert.strictEqual(createSessionCalled, false);
+        assert.strictEqual(receivedOptions.securityLevel, snmp.SecurityLevel.noAuthNoPriv);
+
+        // Restore originals
+        snmp.createV3Session = originalCreateV3Session;
+        snmp.createSession = originalCreateSession;
+    });
+});