initial commit

Author: rauwebieten

.gitignore

@@ -0,0 +1,3 @@
+.idea
+vendor
+composer.lock

composer.json

@@ -0,0 +1,12 @@
+{
+  "name": "rauwebieten/psr7-partial-download",
+  "require": {
+    "php": ">=5.4.0",
+    "psr/http-message": "^1.0.1"
+  },
+  "autoload": {
+    "psr-4": {
+      "RauweBieten\\Psr7PartialDownload\\": "src/"
+    }
+  }
+}

src/Psr7PartialDownload.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace RauweBieten\SlimPartialDownload;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+class Psr7PartialDownload
+{
+    public function sendFile(ServerRequestInterface $request, ResponseInterface $response, $filePath, $fileName, $contentType = 'application/octet-stream')
+    {
+        if (!file_exists($filePath)) {
+            throw new \Exception("File not found: $filePath");
+        }
+
+        if (!is_readable($filePath)) {
+            throw new \Exception("File not readable: $filePath");
+        }
+
+        // remove headers hat might unnecessarily clutter up the output
+        $response = $response->withoutHeader('Cache-Control');
+        $response = $response->withoutHeader('Pragma');
+
+        // default action is to send the entire file
+        $byteOffset = 0;
+        $byteLength = $fileSize = filesize($filePath);
+
+        $response = $response->withHeader('Accept-Ranges', 'bytes');
+        $response = $response->withHeader('Content-Disposition', "attachment; filename=$fileName");
+
+        $server = $request->getServerParams();
+
+        if (isset($server['HTTP_RANGE']) && preg_match('%bytes=(\d+)-(\d+)?%i', $server['HTTP_RANGE'], $match)) {
+            $byteOffset = (int)$match[1];
+
+            if (isset($match[2])) {
+                $finishBytes = (int)$match[2];
+                $byteLength = $finishBytes+1;
+            } else {
+                $finishBytes = $fileSize - 1;
+            }
+            $response = $response->withStatus(206, 'Partial Content');
+            $response = $response->withHeader('Content-Range', "bytes {$byteOffset}-{$finishBytes}/{$fileSize}");
+        }
+
+        $byteRange = $byteLength - $byteOffset;
+        $response = $response->withHeader('Content-Langth', $byteRange);
+        $response = $response->withHeader('Expires', date('D, d M Y H:i:s', time() + 60*60*24*90) . ' GMT');
+
+        $bufferSize = 512*16;
+        $bytePool = $byteRange;
+
+        if (!$fh = fopen($filePath, 'r')) {
+            throw new \Exception("Could not get filehandler for reading: $filePath");
+        }
+
+        if (fseek($fh, $byteOffset, SEEK_SET) == -1) {
+            throw new \Exception("Could not seek to offset $byteOffset in file: $filePath");
+        }
+
+        while ($bytePool > 0) {
+            $chunkSizeRequested = min($bufferSize, $bytePool);
+            $buffer = fread($fh, $chunkSizeRequested);
+            $chunkSizeActual = strlen($buffer);
+
+            if ($chunkSizeActual == 0) {
+                throw new \Exception("Chunksize became 0");
+            }
+
+            $bytePool-= $chunkSizeActual;
+
+            $response->write($buffer);
+        }
+
+        return $response;
+    }
+}