improvements

- dashboard defaults to all watchers, added "*" to explicitly include all watchers too.
- added portInUse check.
- added proper exception handling for httpcheck promise

src/lib/settings.js

@@ -45,22 +45,14 @@ module.exports = {
                 sendgrid : null
 
             }, rawSettings);
-
-            for (const name in rawSettings.dashboards){
-
-                let dashboard = rawSettings.dashboards[name];
-
-                rawSettings.dashboards[name] = Object.assign({
-                    __name : name,  // node name, attached here for convenience
-                    __safeName : sanitize(name), // nodename, made safe for filesystems
-                    name : name,    // users can add their own convenient name, if not this defaults to node name
-                    watchers : ''   //force empty list
-                }, dashboard);
-            }
 
+            let allWatcherNames = [];
+            // process watchers first, we need these to process dashboards
             for (const name in rawSettings.watchers){
 
                 let watcher = rawSettings.watchers[name];
+
+                allWatcherNames.push(name);
 
                 rawSettings.watchers[name] = Object.assign({
                     __name : name,
@@ -72,6 +64,22 @@ module.exports = {
                 }, watcher);
             }
 
+            for (const name in rawSettings.dashboards){
+
+                let dashboard = rawSettings.dashboards[name];
+
+                rawSettings.dashboards[name] = Object.assign({
+                    __name : name,  // node name, attached here for convenience
+                    __safeName : sanitize(name), // nodename, made safe for filesystems
+                    name : name,    // users can add their own convenient name, if not this defaults to node name
+                    watchers : '*'  // force to all watchers
+                }, dashboard);
+
+                // if dashboard is set to * watchers, replace it's watchers list with literal names of all watchers
+                if (rawSettings.dashboards[name].watchers.trim() === '*')
+                    rawSettings.dashboards[name].watchers = allWatcherNames.join(',');
+            }
+
             _settings = rawSettings;
 
             // default values

src/package.json

@@ -15,6 +15,7 @@
     "dependencies": {
         "handlebars-layouts": "3.1.4",
         "handlebars": "4.7.3",
+        "netcat": "1.5.0",
         "jsonfile": "5.0.0",
         "s-ago": "2.0.1",
         "js-yaml": "3.13.1",

src/routes/dashboard.js

@@ -36,8 +36,10 @@ module.exports = function(app){
         let cronJobs = daemon.cronJobs.slice(0).filter((job)=>{
             if (!job.config.enabled)
                 return null;
+
             if (!dashboardWatchers.includes(job.config.__name))
                 return null;
+
             return job;
         }); 
 

src/settings.yml

@@ -31,12 +31,16 @@ watchers:
         url: http://example.com
         # call this script to perform up test 
         test: user/example
-        recipients :  me,bob 
+        recipients :  me,bob
+    servicecheck:
+        interval: "1 * * * *" 
+        host: 127.0.0.1
+        port: 3000
+        test : system/portInUse
 
 dashboards:
     all:
         # name is optional, node name "all" will be use as fallback
         name : All the things
-        watchers: example, another
     single:
         watchers: example

src/tests/system/httpcheck.js

@@ -9,24 +9,27 @@ module.exports = async function(watcher){
         throw `Watcher "${watcher.__name}" is missing a url. test/system/basic requires a url`;
 
     return new Promise((resolve, reject)=>{
-        let code = null;
-
-        request( { uri: watcher.url }, 
-            function(error, response) {
-                if (error){
-                    if (error.errno === 'ENOTFOUND' || error.errno === 'EAI_AGAIN')  
-                        error = `${watcher.url} could not be reached.`;
-
-                    return reject(error);
+        try {
+            let code = null;
+            request( { uri: watcher.url }, 
+                function(error, response) {
+                    if (error){
+                        if (error.errno === 'ENOTFOUND' || error.errno === 'EAI_AGAIN')  
+                            error = `${watcher.url} could not be reached.`;
+
+                        return reject(error);
+                    }
+
+                    if (code && (code < 200 || code > 299)) // allow all code 2**
+                        return reject(`Unexpected HTTP code ${code}`);
+
+                    resolve(response);
                 }
-
-                if (code && (code < 200 || code > 299)) // allow all code 2**
-                    return reject(`Unexpected HTTP code ${code}`);
-
-                resolve(response);
-            }
-        ).on('response', function(response) {
-            code = response.statusCode;
-        })
+            ).on('response', function(response) {
+                code = response.statusCode;
+            })
+        } catch(ex){
+            reject(ex);
+        }
     });
 }

src/tests/system/portInUse.js

@@ -0,0 +1,26 @@
+/**
+ * Uses Netcat to check if a TCP port is in use
+ */
+const NetcatClient = require('netcat/client');
+
+module.exports = async function(watcher){
+    if (!watcher.host)
+        throw `Watcher "${watcher.__name}" is missing a "host" entry.`;
+
+    if (!watcher.port)
+        throw `Watcher "${watcher.__name}" is missing a "port" entry.`;
+
+    return new Promise((resolve, reject)=>{
+        try {
+            const nc = new NetcatClient();
+            nc.addr(watcher.host).scan(watcher.port, function(ports){
+                if (ports[watcher.port] === 'open')
+                    return resolve('port open');
+
+                return reject('port closed');
+            })
+        }catch(ex){
+            reject(ex);
+        }
+    });
+}