From 2fb022461ebd95251dec7918e63279a5f594f885 Mon Sep 17 00:00:00 2001
From: = <=>
Date: Fri, 9 Feb 2024 22:39:08 +0200
Subject: [PATCH] First implementation

---
 .gitignore      |  3 +++
 README.md       | 36 +++++++++++++++++++++++++++++++++-
 composer.json   | 17 ++++++++++++++++
 example.php     | 14 +++++++++++++
 src/Monitor.php | 52 +++++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 121 insertions(+), 1 deletion(-)
 create mode 100644 .gitignore
 create mode 100644 composer.json
 create mode 100644 example.php
 create mode 100644 src/Monitor.php

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..8925195
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.idea
+vendor
+composer.lock
\ No newline at end of file
diff --git a/README.md b/README.md
index 1dd2400..fb958a0 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,35 @@
-# php-tail-f
\ No newline at end of file
+# tail -f for PHP
+
+A simple implementation to provide "tail -f" functionality in PHP code. Allows you to monitor newly added lines to a given file.
+
+This class is designed for implementation within a PHP daemon, specifically excluding its suitability for PHP scripts that generate output for web browsers.
+
+It is a lightweight class that minimally consumes RAM, CPU, or disk I/O resources.
+
+## Sample usage
+
+```php
+<?php
+
+use Nicodemuz\PhpTailF\Monitor;
+
+require 'vendor/autoload.php';
+
+$monitor = new Monitor(
+    filePath: '/tmp/test.log',
+    sleepMicroseconds: 500000,
+);
+
+foreach ($monitor->run() as $output) {
+    echo $output;
+}
+```
+
+
+## Authors
+
+* [Nico Hiort af Ornäs](https://github.com/nicodemuz)
+
+## Credits
+
+Based on the work from https://github.com/Basch3000/php-tail
\ No newline at end of file
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..3f81e10
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,17 @@
+{
+    "name": "nicodemuz/php-tail-f",
+    "description": "Provides tail -f functionailty to watch changes in files",
+    "type": "library",
+    "license": "MIT",
+    "autoload": {
+        "psr-4": {
+            "Nicodemuz\\PhpTailF\\": "src/"
+        }
+    },
+    "authors": [
+        {
+            "name": "Nico Hiort af Ornäs"
+        }
+    ],
+    "require": {}
+}
diff --git a/example.php b/example.php
new file mode 100644
index 0000000..4deb60b
--- /dev/null
+++ b/example.php
@@ -0,0 +1,14 @@
+<?php
+
+use Nicodemuz\PhpTailF\Monitor;
+
+require 'vendor/autoload.php';
+
+$monitor = new Monitor(
+    filePath: '/tmp/test.log',
+    sleepMicroseconds: 500000,
+);
+
+foreach ($monitor->run() as $output) {
+    echo $output;
+}
diff --git a/src/Monitor.php b/src/Monitor.php
new file mode 100644
index 0000000..7a3a821
--- /dev/null
+++ b/src/Monitor.php
@@ -0,0 +1,52 @@
+<?php
+
+namespace Nicodemuz\PhpTailF;
+
+use Generator;
+
+class Monitor
+{
+    private int $lastModified = 0;
+    private int $lastSize = 0;
+
+    public function __construct(
+        private readonly string $filePath,
+        private readonly int $sleepMicroseconds
+    ) {
+    }
+
+    public function run(): Generator
+    {
+        $filePointer = fopen($this->filePath, "r");
+        while(true)
+        {
+            clearstatcache(false, $this->filePath);
+            $modified = filemtime($this->filePath);
+
+            if($modified == $this->lastModified) {
+                usleep($this->sleepMicroseconds);
+                continue;
+            }
+
+            $this->lastModified = $modified;
+
+            $lastSize = filesize($this->filePath);
+            $bytesAdded = $lastSize - $this->lastSize;
+            $this->lastSize = $lastSize;
+
+            if($bytesAdded == $lastSize)
+            {
+                fseek($filePointer, $lastSize);
+                usleep($this->sleepMicroseconds);
+                continue;
+            }
+
+            fseek($filePointer, -$bytesAdded);
+            $added = fread($filePointer, $lastSize);
+
+            yield $added;
+
+            usleep($this->sleepMicroseconds);
+        }
+    }
+}
\ No newline at end of file