Merge pull request #125 from clue-labs/examples

Restructure examples to ease getting started

Author: jsor

examples/04-signals.php

@@ -2,11 +2,18 @@
 
 require __DIR__ . '/../vendor/autoload.php';
 
+if (!defined('SIGINT')) {
+    fwrite(STDERR, 'Not supported on your platform (ext-pcntl missing or Windows?)' . PHP_EOL);
+    exit(1);
+}
+
 $loop = React\EventLoop\Factory::create();
 
 $loop->addSignal(SIGINT, $func = function ($signal) use ($loop, &$func) {
     echo 'Signal: ', (string)$signal, PHP_EOL;
     $loop->removeSignal(SIGINT, $func);
 });
 
+echo 'Listening for SIGINT. Use "kill -SIGINT ' . getmypid() . '" or CTRL+C' . PHP_EOL;
+
 $loop->run();

examples/11-consume-stdin.php

@@ -4,19 +4,23 @@
 
 require __DIR__ . '/../vendor/autoload.php';
 
-if (stream_set_blocking(STDIN, false) !== true) {
-    fwrite(STDERR, 'ERROR: Unable to set STDIN non-blocking' . PHP_EOL);
+if (!defined('STDIN') || stream_set_blocking(STDIN, false) !== true) {
+    fwrite(STDERR, 'ERROR: Unable to set STDIN non-blocking (not CLI or Windows?)' . PHP_EOL);
     exit(1);
 }
 
 $loop = Factory::create();
 
+// read everything from STDIN and report number of bytes
+// for illustration purposes only, should use react/stream instead
 $loop->addReadStream(STDIN, function ($stream) use ($loop) {
     $chunk = fread($stream, 64 * 1024);
 
     // reading nothing means we reached EOF
     if ($chunk === '') {
         $loop->removeReadStream($stream);
+        stream_set_blocking($stream, true);
+        fclose($stream);
         return;
     }
 

examples/12-generate-yes.php

@@ -10,20 +10,22 @@
 
 $loop = React\EventLoop\Factory::create();
 
-$stdout = STDOUT;
-if (stream_set_blocking($stdout, false) !== true) {
-    fwrite(STDERR, 'ERROR: Unable to set STDOUT non-blocking' . PHP_EOL);
+if (!defined('STDOUT') || stream_set_blocking(STDOUT, false) !== true) {
+    fwrite(STDERR, 'ERROR: Unable to set STDOUT non-blocking (not CLI or Windows?)' . PHP_EOL);
     exit(1);
 }
 
-$loop->addWriteStream($stdout, function () use ($loop, $stdout, &$data) {
+// write data to STDOUT whenever its write buffer accepts data
+// for illustrations purpose only, should use react/stream instead
+$loop->addWriteStream(STDOUT, function ($stdout) use ($loop, &$data) {
     // try to write data
     $r = fwrite($stdout, $data);
 
     // nothing could be written despite being writable => closed
     if ($r === 0) {
         $loop->removeWriteStream($stdout);
         fclose($stdout);
+        stream_set_blocking($stdout, true);
         fwrite(STDERR, 'Stopped because STDOUT closed' . PHP_EOL);
 
         return;

examples/13-http-client-blocking.php

@@ -0,0 +1,35 @@
+<?php
+
+use React\EventLoop\Factory;
+
+require __DIR__ . '/../vendor/autoload.php';
+
+$loop = Factory::create();
+
+// connect to www.google.com:80 (blocking call!)
+// for illustration purposes only, should use react/socket instead
+$stream = stream_socket_client('tcp://www.google.com:80');
+if (!$stream) {
+    exit(1);
+}
+stream_set_blocking($stream, false);
+
+// send HTTP request
+fwrite($stream, "GET / HTTP/1.1\r\nHost: www.google.com\r\nConnection: close\r\n\r\n");
+
+// wait for HTTP response
+$loop->addReadStream($stream, function ($stream) use ($loop) {
+    $chunk = fread($stream, 64 * 1024);
+
+    // reading nothing means we reached EOF
+    if ($chunk === '') {
+        echo '[END]' . PHP_EOL;
+        $loop->removeReadStream($stream);
+        fclose($stream);
+        return;
+    }
+
+    echo $chunk;
+});
+
+$loop->run();

examples/14-http-client-async.php

@@ -0,0 +1,63 @@
+<?php
+
+use React\EventLoop\Factory;
+
+require __DIR__ . '/../vendor/autoload.php';
+
+$loop = Factory::create();
+
+// resolve hostname before establishing TCP/IP connection (resolving DNS is still blocking here)
+// for illustration purposes only, should use react/socket or react/dns instead!
+$ip = gethostbyname('www.google.com');
+if (ip2long($ip) === false) {
+    echo 'Unable to resolve hostname' . PHP_EOL;
+    exit(1);
+}
+
+// establish TCP/IP connection (non-blocking)
+// for illustraction purposes only, should use react/socket instead!
+$stream = stream_socket_client('tcp://' . $ip . ':80', $errno, $errstr, null, STREAM_CLIENT_CONNECT | STREAM_CLIENT_ASYNC_CONNECT);
+if (!$stream) {
+    exit(1);
+}
+stream_set_blocking($stream, false);
+
+// print progress every 10ms
+echo 'Connecting';
+$timer = $loop->addPeriodicTimer(0.01, function () {
+    echo '.';
+});
+
+// wait for connection success/error
+$loop->addWriteStream($stream, function ($stream) use ($loop, $timer) {
+    $loop->removeWriteStream($stream);
+    $loop->cancelTimer($timer);
+
+    // check for socket error (connection rejected)
+    if (stream_socket_get_name($stream, true) === false) {
+        echo '[unable to connect]' . PHP_EOL;
+        exit(1);
+    } else {
+        echo '[connected]' . PHP_EOL;
+    }
+
+    // send HTTP request
+    fwrite($stream, "GET / HTTP/1.1\r\nHost: www.google.com\r\nConnection: close\r\n\r\n");
+
+    // wait for HTTP response
+    $loop->addReadStream($stream, function ($stream) use ($loop) {
+        $chunk = fread($stream, 64 * 1024);
+
+        // reading nothing means we reached EOF
+        if ($chunk === '') {
+            echo '[END]' . PHP_EOL;
+            $loop->removeReadStream($stream);
+            fclose($stream);
+            return;
+        }
+
+        echo $chunk;
+    });
+});
+
+$loop->run();

examples/21-http-server.php

@@ -4,9 +4,15 @@
 
 $loop = React\EventLoop\Factory::create();
 
+// start TCP/IP server on localhost:8080
+// for illustration purposes only, should use react/socket instead
 $server = stream_socket_server('tcp://127.0.0.1:8080');
-stream_set_blocking($server, 0);
+if (!$server) {
+    exit(1);
+}
+stream_set_blocking($server, false);
 
+// wait for incoming connections on server socket
 $loop->addReadStream($server, function ($server) use ($loop) {
     $conn = stream_socket_accept($server);
     $data = "HTTP/1.1 200 OK\r\nContent-Length: 3\r\n\r\nHi\n";