Added logger as YDB config

Added logger as YDB config

Author: ilyakharev

CHANGELOG.md

@@ -1,3 +1,4 @@
+* add logger as Ydb config
 * added snapshot mode in noninteractive transaction
 
 ## 1.12.0

README.md

@@ -546,3 +546,19 @@ Methods of the query builder:
 - `txControl(\Ydb\Table\TransactionControl $tx_control)` - transaction control with custom settings
 
 You can chain these methods for convenience.
+
+## Logging
+
+For logging purposes, you need use class, which implements `\Psr\Log\LoggerInterface`.
+YDB-PHP-SDK has build-in loggers in `YdbPlatform\Ydb\Logger` namespace:
+* `NullLogger` - default
+* `SimpleStdLogger($level)` - logger, which push logs in STDERR. 
+
+Example of using:
+```php
+$config = [
+    'logger' => new \YdbPlatform\Ydb\Logger\SimpleStdLogger(\YdbPlatform\Ydb\Logger\SimpleStdLogger::INFO)
+]
+$ydb = new \YdbPlatform\Ydb\Ydb($config);
+```
+

src/Ydb.php

@@ -107,10 +107,14 @@ public function __construct($config = [], LoggerInterface $logger = null)
         $this->database = $config['database'] ?? null;
         $this->iam_config = $config['iam_config'] ?? [];
 
-        if ($logger){
-            $this->logger = $logger;
+        if (!is_null($logger) && isset($config['logger'])){
+            throw new \Exception('Logger set in 2 places');
+        } else if (isset($config['logger'])) {
+            $this->setLogger($config['logger']);
+        } else if ($logger) {
+            $this->setLogger($logger);
         } else {
-            $this->logger = new NullLogger();
+            $this->setLogger(new NullLogger());
         }
 
         $this->retry = new Retry($this->logger);
@@ -351,4 +355,21 @@ public function discoveryInterval()
     {
         return $this->discoveryInterval;
     }
+
+    /**
+     * @return LoggerInterface|NullLogger
+     */
+    public function getLogger()
+    {
+        return $this->logger;
+    }
+
+    /**
+     * @param LoggerInterface $logger
+     * @return void
+     */
+    protected function setLogger(LoggerInterface $logger){
+        $this->logger = $logger;
+    }
+
 }

tests/LoggerCheckTest.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace YdbPlatform\Ydb\Test;
+
+use PHPUnit\Framework\TestCase;
+use YdbPlatform\Ydb\Auth\Implement\AnonymousAuthentication;
+use YdbPlatform\Ydb\Logger\NullLogger;
+use YdbPlatform\Ydb\Logger\SimpleStdLogger;
+use YdbPlatform\Ydb\Ydb;
+
+class LoggerCheckTest extends TestCase{
+
+    public function testExceptExceptionInConfigs(){
+        $config = [
+            'logger' => new SimpleStdLogger(7)
+        ];
+        $this->expectException('Exception');
+        new Ydb($config, new NullLogger());
+    }
+    public function testCheckUseLoggerFromConfig(){
+        $logger = new SimpleStdLogger(7);
+        $config = [
+            'logger' => $logger
+        ];
+        $ydb = new Ydb($config);
+        $this->assertEquals($logger, $ydb->getLogger());
+    }
+    public function testCheckUseLoggerFromParam(){
+        $logger = new SimpleStdLogger(7);
+        $config = [];
+        $ydb = new Ydb($config, $logger);
+        $this->assertEquals($logger, $ydb->getLogger());
+    }
+    public function testCheckUseNullLogger(){
+        $config = [];
+        $ydb = new Ydb($config);
+        $this->assertInstanceOf(NullLogger::class, $ydb->getLogger());
+    }
+
+    public function testThrowExceptionOnNonLoggerObject(){
+        $config = [
+            'logger'    => new AnonymousAuthentication()
+        ];
+        $this->expectException('TypeError');
+        $ydb = new Ydb($config);
+        $this->assertInstanceOf(NullLogger::class, $ydb->getLogger());
+    }
+}