Improve Snmpsim usage to ease testing (#15471)

* Snmpsim use python venv
Patch to enable listening while minimizing output
Update lnms dev:simulate, tests, and ./scripts/save-test-data.php
removed old option to start snmpsim from older scripts, use lnms dev:simulate

* Apply fixes from StyleCI

* various fixes

* Remove patch official package is updated

---------

Co-authored-by: StyleCI Bot <bot@styleci.io>

.github/workflows/test.yml

@@ -99,7 +99,7 @@ jobs:
         name: Pip install
         run: |
           python3 -m pip install --upgrade pip
-          python3 -m pip install --upgrade --user snmpsim pylint python-memcached mysqlclient
+          python3 -m pip install --upgrade --user pylint python-memcached mysqlclient
       -
         name: Composer validate
         run: |
@@ -128,6 +128,10 @@ jobs:
         name: Composer install
         run: |
           composer install --prefer-dist --no-interaction --no-progress
+      -
+        name: Snmpsim setup
+        run: |
+          php lnms dev:simulate --setup-venv
       -
         name: Artisan dusk:chrome-driver
         if: matrix.skip-web-check != '1'
@@ -168,7 +172,7 @@ jobs:
         name: Start SNMP
         if: matrix.skip-unit-check != '1'
         run: |
-          ~/.local/bin/snmpsim-command-responder-lite --data-dir=tests/snmpsim --agent-udpv4-endpoint=127.1.6.2:1162 --log-level=error --logging-method=file:/tmp/snmpsimd.log &
+          .python_venvs/snmpsim/bin/snmpsim-command-responder-lite --data-dir=tests/snmpsim --agent-udpv4-endpoint=127.1.6.2:1162 --log-level=error --logging-method=file:/tmp/snmpsimd.log &
       -
         name: lnms dev:check ci
         run: |

LibreNMS/Util/CiHelper.php

@@ -295,7 +295,7 @@ class CiHelper
             $py_lint_cmd = [$this->checkPythonExec('pylint'), '-E', '-j', '0'];
 
             $files = $this->flags['full']
-                ? explode(PHP_EOL, rtrim(shell_exec("find . -name '*.py' -not -path './vendor/*' -not -path './tests/*'")))
+                ? explode(PHP_EOL, rtrim(shell_exec("find . -name '*.py' -not -path './vendor/*' -not -path './tests/*' -not -path './.python_venvs/*'")))
                 : $this->changed['python'];
 
             $py_lint_cmd = array_merge($py_lint_cmd, $files);

LibreNMS/Util/ModuleTestHelper.php

@@ -560,17 +560,17 @@ class ModuleTestHelper
         }
 
         // Remove existing device in case it didn't get removed previously
-        if (($existing_device = device_by_name($snmpsim->getIp())) && isset($existing_device['device_id'])) {
+        if (($existing_device = device_by_name($snmpsim->ip)) && isset($existing_device['device_id'])) {
             delete_device($existing_device['device_id']);
         }
 
         // Add the test device
         try {
             $new_device = new Device([
-                'hostname' => $snmpsim->getIp(),
+                'hostname' => $snmpsim->ip,
                 'version' => 'v2c',
                 'community' => $this->file_name,
-                'port' => $snmpsim->getPort(),
+                'port' => $snmpsim->port,
                 'disabled' => 1, // disable to block normal pollers
             ]);
             (new ValidateDeviceAndCreate($new_device, true))->execute();
@@ -647,7 +647,7 @@ class ModuleTestHelper
         $data = array_merge_recursive($data, $this->dumpDb($device_id, $polled_modules, 'poller'));
 
         // Remove the test device, we don't need the debug from this
-        if ($device['hostname'] == $snmpsim->getIp()) {
+        if ($device['hostname'] == $snmpsim->ip) {
             Debug::set(false);
             delete_device($device_id);
         }

LibreNMS/Util/Snmpsim.php

@@ -25,166 +25,70 @@
 
 namespace LibreNMS\Util;
 
-use App;
+use Symfony\Component\Process\Process;
-use LibreNMS\Config;
-use LibreNMS\Proc;
 
-class Snmpsim
+class Snmpsim extends Process
 {
-    private $snmprec_dir;
+    public readonly string $snmprec_dir;
-    private $ip;
-    private $port;
-    private $log;
-    /** @var Proc */
-    private $proc;
 
-    public function __construct($ip = '127.1.6.1', $port = 1161, $log = '/tmp/snmpsimd.log')
+    public function __construct(
+        public readonly string $ip = '127.1.6.1',
+        public readonly int $port = 1161,
+        public readonly ?string $log_method = null)
     {
-        $this->ip = $ip;
+        $this->snmprec_dir = base_path('tests/snmpsim');
-        $this->port = $port;
+
-        $this->log = $log;
+        $cmd = [
-        $this->snmprec_dir = Config::get('install_dir') . '/tests/snmpsim/';
+            $this->getVenvPath('bin/snmpsim-command-responder-lite'),
+            "--data-dir={$this->snmprec_dir}",
+            "--agent-udpv4-endpoint={$this->ip}:{$this->port}",
+            '--log-level=error',
+        ];
+
+        if ($this->log_method !== null) {
+            $cmd[] = "--logging-method=$this->log_method";
+        }
+
+        parent::__construct($cmd, base_path());
+        $this->setTimeout(null); // no timeout by default
     }
 
-    /**
+    public function waitForStartup(): string
-     * Run snmpsimd and fork it into the background
-     * Captures all output to the log
-     *
-     * @param  int  $wait  Wait for x seconds after starting before returning
-     */
-    public function fork($wait = 2)
     {
-        if ($this->isRunning()) {
+        $listen = $this->ip . ':' . $this->port;
-            echo "Snmpsim is already running!\n";
+        $this->waitUntil(function ($type, $buffer) use ($listen, &$last) {
+            $last = $buffer;
 
-            return;
+            return $type == Process::ERR && str_contains($buffer, $listen);
-        }
+        });
 
-        $cmd = $this->getCmd();
+        return trim($last);
+    }
 
-        if (App::runningInConsole()) {
+    public function isVenvSetUp(): bool
-            echo "Starting snmpsim listening on {$this->ip}:{$this->port}... \n";
+    {
-            d_echo($cmd);
+        return is_executable($this->getVenvPath('bin/snmpsim-command-responder-lite'));
-        }
+    }
 
-        $this->proc = new Proc($cmd);
+    public function setupVenv($print_output = false): void
+    {
+        $snmpsim_venv_path = $this->getVenvPath();
 
-        if ($wait) {
+        if (! $this->isVenvSetUp()) {
-            sleep($wait);
+            \Log::info('Setting up snmpsim virtual env in ' . $snmpsim_venv_path);
-        }
 
-        if (App::runningInConsole() && ! $this->proc->isRunning()) {
+            $setupProcess = new Process(['python', '-m', 'venv', $snmpsim_venv_path]);
-            // if starting failed, run snmpsim again and output to the console and validate the data
+            $setupProcess->setTty($print_output);
-            passthru($this->getCmd(false) . ' --validate-data');
+            $setupProcess->run();
 
-            if (! is_executable($this->findSnmpsimd())) {
+            $installProcess = new Process([$snmpsim_venv_path . '/bin/pip', 'install', 'snmpsim']);
-                echo "\nCould not find snmpsim, you can install it with 'pip install snmpsim-lextudio'.  If it is already installed, make sure snmpsimd, snmpsim-command-responder or snmpsimd.py is in PATH\n";
+            $installProcess->setTty($print_output);
-            } else {
+            $installProcess->run();
-                echo "\nFailed to start Snmpsim. Scroll up for error.\n";
-            }
-            exit(1);
         }
     }
 
-    /**
+    public function getVenvPath(string $subdir = ''): string
-     * Stop and start the running snmpsim process
-     */
-    public function restart()
     {
-        $this->stop();
+        return base_path('.python_venvs/snmpsim/' . $subdir);
-        $this->proc = new Proc($this->getCmd());
-    }
-
-    public function stop()
-    {
-        if (isset($this->proc)) {
-            if ($this->proc->isRunning()) {
-                $this->proc->terminate();
-            }
-            unset($this->proc);
-        }
-    }
-
-    /**
-     * Run snmpsimd but keep it in the foreground
-     * Outputs to stdout
-     */
-    public function run()
-    {
-        echo "Starting snmpsim listening on {$this->ip}:{$this->port}... \n";
-        shell_exec($this->getCmd(false));
-    }
-
-    public function isRunning()
-    {
-        if (isset($this->proc)) {
-            return $this->proc->isRunning();
-        }
-
-        return false;
-    }
-
-    /**
-     * @return string
-     */
-    public function getDir()
-    {
-        return $this->snmprec_dir;
-    }
-
-    /**
-     * @return string
-     */
-    public function getIp()
-    {
-        return $this->ip;
-    }
-
-    /**
-     * @return int
-     */
-    public function getPort()
-    {
-        return $this->port;
-    }
-
-    /**
-     * Generate the command for snmpsimd
-     *
-     * @param  bool  $with_log
-     * @return string
-     */
-    private function getCmd($with_log = true)
-    {
-        $cmd = $this->findSnmpsimd();
-
-        $cmd .= " --data-dir={$this->snmprec_dir} --agent-udpv4-endpoint={$this->ip}:{$this->port}";
-
-        if (is_null($this->log)) {
-            $cmd .= ' --logging-method=null';
-        } elseif ($with_log) {
-            $cmd .= " --logging-method=file:{$this->log}";
-        }
-
-        return $cmd;
-    }
-
-    public function __destruct()
-    {
-        // unset $this->proc to make sure it isn't referenced
-        unset($this->proc);
-    }
-
-    public function findSnmpsimd()
-    {
-        $cmd = Config::locateBinary('snmpsimd');
-        if (! is_executable($cmd)) {
-            $cmd = Config::locateBinary('snmpsim-command-responder');
-            if (! is_executable($cmd)) {
-                $cmd = Config::locateBinary('snmpsimd.py');
-            }
-        }
-
-        return $cmd;
     }
 }

app/Console/Commands/DevSimulate.php

@@ -8,7 +8,7 @@ use Illuminate\Support\Str;
 use LibreNMS\Util\Snmpsim;
 use Symfony\Component\Console\Input\InputArgument;
 use Symfony\Component\Console\Input\InputOption;
-use Symfony\Component\Process\Process;
+use Symfony\Component\Process\Exception\ProcessSignaledException;
 
 class DevSimulate extends LnmsCommand
 {
@@ -38,6 +38,7 @@ class DevSimulate extends LnmsCommand
         $this->addArgument('file', InputArgument::OPTIONAL);
         $this->addOption('multiple', 'm', InputOption::VALUE_NONE);
         $this->addOption('remove', 'r', InputOption::VALUE_NONE);
+        $this->addOption('setup-venv', mode: InputOption::VALUE_NONE);
     }
 
     /**
@@ -45,12 +46,8 @@ class DevSimulate extends LnmsCommand
      *
      * @return int
      */
-    public function handle()
+    public function handle(): int
     {
-        $this->snmpsim = new Snmpsim();
-        $snmprec_dir = $this->snmpsim->getDir();
-        $listen = $this->snmpsim->getIp() . ':' . $this->snmpsim->getPort();
-
         $file = $this->argument('file');
         if ($file && ! file_exists(base_path("tests/snmpsim/$file.snmprec"))) {
             $this->error("$file does not exist");
@@ -58,45 +55,52 @@ class DevSimulate extends LnmsCommand
             return 1;
         }
 
-        $snmpsim = new Process([
+        $this->snmpsim = new Snmpsim;
-            $this->snmpsim->findSnmpsimd(),
+        if (! $this->snmpsim->isVenvSetUp()) {
-            "--data-dir=$snmprec_dir",
+            $this->line(trans('commands.dev:simulate.setup', ['dir' => $this->snmpsim->getVenvPath()]));
-            "--agent-udpv4-endpoint=$listen",
+            $this->snmpsim->setupVenv($this->getOutput()->isVeryVerbose());
-        ]);
+        }
-        $snmpsim->setTimeout(null);
 
-        $snmpsim->run(function ($type, $buffer) use ($listen) {
+        if ($this->option('setup-venv')) {
-            if (Process::ERR === $type) {
+            return 0; // venv is set up exit
-                if (Str::contains($buffer, $listen)) {
+        }
-                    $this->line(trim($buffer));
-                    $this->started();
-                    $this->line(trans('commands.dev:simulate.exit'));
-                }
-            }
-        });
 
-        if (! $snmpsim->isSuccessful()) {
+        $this->snmpsim->start();
-            $this->line($snmpsim->getErrorOutput());
+        $this->line($this->snmpsim->waitForStartup());
+        $this->started();
+        $this->line(trans('commands.dev:simulate.exit'));
+        try {
+            $this->snmpsim->wait();
+        } catch(ProcessSignaledException $e) {
+            $this->error($e->getMessage());
+
+            return 1;
+        }
+
+        if (! $this->snmpsim->isSuccessful()) {
+            $this->line($this->snmpsim->getErrorOutput());
+
+            return 1;
         }
 
         return 0;
     }
 
-    private function started()
+    private function started(): void
     {
         if ($file = $this->argument('file')) {
             $this->addDevice($file);
         }
     }
 
-    private function addDevice($community)
+    private function addDevice($community): void
     {
         $hostname = $this->option('multiple') ? $community : 'snmpsim';
         $device = Device::firstOrNew(['hostname' => $hostname]);
         $action = $device->exists ? 'updated' : 'added';
 
-        $device->overwrite_ip = $this->snmpsim->getIp();
+        $device->overwrite_ip = $this->snmpsim->ip;
-        $device->port = $this->snmpsim->getPort();
+        $device->port = $this->snmpsim->port;
         $device->snmpver = 'v2c';
         $device->transport = 'udp';
         $device->community = $community;
@@ -112,7 +116,7 @@ class DevSimulate extends LnmsCommand
         }
     }
 
-    private function queueRemoval($device_id)
+    private function queueRemoval($device_id): void
     {
         if (function_exists('pcntl_signal')) {
             pcntl_signal(SIGINT, function () {

lang/en/commands.php

@@ -63,6 +63,7 @@ return [
         'exit' => 'Ctrl-C to stop',
         'removed' => 'Device :id removed',
         'updated' => 'Device :hostname (:id) updated',
+        'setup' => 'Setting up snmpsim venv in :dir',
     ],
     'device:add' => [
         'description' => 'Add a new device',

phpstan-baseline.neon

@@ -150,16 +150,6 @@ parameters:
 			count: 1
 			path: LibreNMS/Util/Graph.php
 
-		-
-			message: "#^Property LibreNMS\\\\Util\\\\Snmpsim\\:\\:\\$proc \\(LibreNMS\\\\Proc\\) in isset\\(\\) is not nullable\\.$#"
-			count: 2
-			path: LibreNMS/Util/Snmpsim.php
-
-		-
-			message: "#^Unreachable statement \\- code above always terminates\\.$#"
-			count: 1
-			path: LibreNMS/Util/Snmpsim.php
-
 		-
 			message: "#^Static method Silber\\\\Bouncer\\\\BouncerFacade\\:\\:role\\(\\) invoked with 0 parameters, 1 required\\.$#"
 			count: 1

scripts/collect-snmp-data.php

@@ -5,7 +5,6 @@ use Illuminate\Support\Str;
 use LibreNMS\Exceptions\InvalidModuleException;
 use LibreNMS\Util\Debug;
 use LibreNMS\Util\ModuleTestHelper;
-use LibreNMS\Util\Snmpsim;
 
 $install_dir = realpath(__DIR__ . '/..');
 chdir($install_dir);
@@ -23,18 +22,11 @@ $options = getopt(
         'variant:',
         'file:',
         'debug',
-        'snmpsim',
         'full',
         'help',
     ]
 );
 
-if (isset($options['snmpsim'])) {
-    $snmpsim = new Snmpsim();
-    $snmpsim->run();
-    exit;
-}
-
 if (isset($options['v'])) {
     $variant = $options['v'];
 } elseif (isset($options['variant'])) {

scripts/save-test-data.php

@@ -20,7 +20,6 @@ $options = getopt(
         'no-save',
         'file:',
         'debug',
-        'snmpsim',
         'help',
     ]
 );
@@ -32,12 +31,6 @@ Debug::setVerbose(
     Debug::set(isset($options['d']) || isset($options['debug']))
 );
 
-if (isset($options['snmpsim'])) {
-    $snmpsim = new Snmpsim();
-    $snmpsim->run();
-    exit;
-}
-
 if (isset($options['h'])
     || isset($options['help'])
     || ! (isset($options['o']) || isset($options['os']) || isset($options['m']) || isset($options['modules']))
@@ -120,9 +113,10 @@ if (isset($options['f'])) {
 
 // Now use the saved data to update the saved database data
 $snmpsim = new Snmpsim();
-$snmpsim->fork();
+$snmpsim->setupVenv();
-$snmpsim_ip = $snmpsim->getIp();
+$snmpsim->start();
-$snmpsim_port = $snmpsim->getPort();
+echo "Waiting for snmpsim to initialize...\n";
+$snmpsim->waitForStartup();
 
 if (! $snmpsim->isRunning()) {
     echo "Failed to start snmpsim, make sure it is installed, working, and there are no bad snmprec files.\n";
@@ -130,8 +124,6 @@ if (! $snmpsim->isRunning()) {
     exit(1);
 }
 
-echo "Pausing 10 seconds to allow snmpsim to initialize...\n";
-sleep(10);
 echo "\n";
 
 try {

tests/OSDiscoveryTest.php

@@ -143,9 +143,9 @@ class OSDiscoveryTest extends TestCase
     private function genDevice($community): Device
     {
         return new Device([
-            'hostname' => $this->getSnmpsim()->getIP(),
+            'hostname' => $this->getSnmpsim()->ip,
             'snmpver' => 'v2c',
-            'port' => $this->getSnmpsim()->getPort(),
+            'port' => $this->getSnmpsim()->port,
             'timeout' => 3,
             'retries' => 0,
             'snmp_max_repeaters' => 10,

tests/bootstrap.php

@@ -36,10 +36,11 @@ chdir($install_dir);
 ini_set('display_errors', '1');
 //error_reporting(E_ALL & ~E_WARNING);
 
-$snmpsim = new Snmpsim('127.1.6.2', 1162, null);
+$snmpsim = new Snmpsim('127.1.6.2', 1162);
 if (getenv('SNMPSIM')) {
     if (! getenv('GITHUB_ACTIONS')) {
-        $snmpsim->fork(6);
+        $snmpsim->setupVenv();
+        $snmpsim->start();
     }
 
     // make PHP hold on a reference to $snmpsim so it doesn't get destructed