SNMP Initial Commits

This commit introduces a new SNMP monitor feature to the application, allowing users to monitor devices using SNMP (Simple Network Management Protocol).

db/knex_migrations/2024-04-26-0000-snmp-monitor.js

@@ -0,0 +1,10 @@
+exports.up = function (knex) {
+    return knex.schema
+        .alterTable("monitor", function (table) {
+            table.string("snmp_community_string", 255).defaultTo("public"); // Add community_string column
+            table.string("snmp_oid").notNullable(); // Add oid column
+            table.enum("snmp_version", ["1", "2c", "3"]).defaultTo("2c"); // Add snmp_version column with enum values
+            table.float("snmp_control_value").notNullable(); // Add control_value column as float
+            table.string("snmp_condition").notNullable(); // Add oid column
+        });
+};

package.json

@@ -137,6 +137,7 @@
         "redbean-node": "~0.3.0",
         "redis": "~4.5.1",
         "semver": "~7.5.4",
+        "snmp-native": "^1.2.0",
         "socket.io": "~4.6.1",
         "socket.io-client": "~4.6.1",
         "socks-proxy-agent": "6.1.1",

server/monitor-types/snmp.js

@@ -0,0 +1,69 @@
+const { MonitorType } = require("./monitor-type");
+const { UP, DOWN } = require("../../src/util");
+const snmp = require("snmp-native");
+
+class SNMPMonitorType extends MonitorType {
+    name = "snmp";
+
+    /**
+     * Checks the SNMP value against the condition and control value.
+     * @param {object} monitor The monitor object associated with the check.
+     * @param {object} heartbeat The heartbeat object to update.
+     * @param {object} _server Unused server object.
+     */
+    async check(monitor, heartbeat, _server) {
+        try {
+            const session = new snmp.Session({ host: monitor.ipAddress, community: monitor.snmpCommunityString, version: monitor.snmpVersion });
+
+            session.get({ oid: monitor.snmpOid }, (err, varbinds) => {
+                if (err) {
+                    heartbeat.status = DOWN;
+                    heartbeat.msg = `Error: ${err.message}`;
+                    return;
+                }
+
+                // Assuming only one varbind is returned
+                const value = varbinds[0].value;
+
+                // Convert value to appropriate type based on SNMP type (assuming it's integer or string for simplicity)
+                const numericValue = parseInt(value);
+                const stringValue = value.toString();
+
+                // Check against condition and control value
+                switch (monitor.snmpCondition) {
+                    case '>':
+                        heartbeat.status = numericValue > monitor.snmpControlValue ? UP : DOWN;
+                        break;
+                    case '>=':
+                        heartbeat.status = numericValue >= monitor.snmpControlValue ? UP : DOWN;
+                        break;
+                    case '<':
+                        heartbeat.status = numericValue < monitor.snmpControlValue ? UP : DOWN;
+                        break;
+                    case '<=':
+                        heartbeat.status = numericValue <= monitor.snmpControlValue ? UP : DOWN;
+                        break;
+                    case '==':
+                        heartbeat.status = value === monitor.snmpControlValue ? UP : DOWN;
+                        break;
+                    case 'contains':
+                        heartbeat.status = stringValue.includes(monitor.snmpControlValue) ? UP : DOWN;
+                        break;
+                    default:
+                        heartbeat.status = DOWN;
+                        heartbeat.msg = `Invalid condition: ${monitor.snmpCondition}`;
+                }
+
+                session.close();
+            });
+        } catch (err) {
+            heartbeat.status = DOWN;
+            heartbeat.msg = `Error: ${err.message}`;
+        }
+    }
+
+}
+
+module.exports = {
+    SNMPMonitorType,
+};

server/uptime-kuma-server.js

@@ -113,6 +113,7 @@ class UptimeKumaServer {
         UptimeKumaServer.monitorTypeList["tailscale-ping"] = new TailscalePing();
         UptimeKumaServer.monitorTypeList["dns"] = new DnsMonitorType();
         UptimeKumaServer.monitorTypeList["mqtt"] = new MqttMonitorType();
+        UptimeKumaServer.monitorTypeList["snmp"] = new SNMPMonitorType();
 
         // Allow all CORS origins (polling) in development
         let cors = undefined;
@@ -516,3 +517,4 @@ const { RealBrowserMonitorType } = require("./monitor-types/real-browser-monitor
 const { TailscalePing } = require("./monitor-types/tailscale-ping");
 const { DnsMonitorType } = require("./monitor-types/dns");
 const { MqttMonitorType } = require("./monitor-types/mqtt");
+const { SNMPMonitorType } = require("./monitor-types/snmp");