finfo = new finfo(FILEINFO_MIME_TYPE, $magicFile); $this->extensionMap = $extensionMap ?: new GeneratedExtensionToMimeTypeMap(); $this->bufferSampleSize = $bufferSampleSize; } public function detectMimeType(string $path, $contents): ?string { $mimeType = is_string($contents) ? (@$this->finfo->buffer($this->takeSample($contents)) ?: null) : null; if ($mimeType !== null && ! in_array($mimeType, self::INCONCLUSIVE_MIME_TYPES)) { return $mimeType; } return $this->detectMimeTypeFromPath($path); } public function detectMimeTypeFromPath(string $path): ?string { $extension = strtolower(pathinfo($path, PATHINFO_EXTENSION)); return $this->extensionMap->lookupMimeType($extension); } public function detectMimeTypeFromFile(string $path): ?string { return @$this->finfo->file($path) ?: null; } public function detectMimeTypeFromBuffer(string $contents): ?string { return @$this->finfo->buffer($this->takeSample($contents)) ?: null; } private function takeSample(string $contents): string { if ($this->bufferSampleSize === null) { return $contents; } return (string) substr($contents, 0, $this->bufferSampleSize); } }