用于href的CodeIgniter base_url（）和用于file_exists（）的getcwd（）

Question

How do I generalise or neutralise the difference between base_url() and getcwd()?

In a view, I want to display both an inline PDF-viewer (using the <object src=''></object>) and the OCR'ed output. Both of these require the same source file, which is located in project/public/corpus/<some_id>/file.pdf (where project is the CodeIgniter root).

The code in the controller can be summarised like this:

    /**
     * Fetch the path to the pdf of the document (OCR is preferred)
     * $handle is a unique identifier
     */
    $object_src = base_url("public/mi-corpus/" . $handle . "/file.pdf");

    $ocr_src = getcwd()."/public/mi-corpus/" . $handle . "/file.pdf";

    // Returns an <object> node from the source
    $this->data['object'] = $this->get_pdf($ocr_src);

    // uses a cloud OCR to parse the source and return OCR'ed text, this is irrelevant. But it does use file_exists($src) to check if the path is valid.
    $this->data['ocr'] = $this->mipreprocessing->open_ocr($ocr_src);

The thing is, when using base_url(), the function file_exists($src) always fails, but the getcwd() concatenation fails when producing a src attribute for the HTML <object>.

I see that base_url() yields a 'real' URL-like string ("http://localhost/" etc.), whereas getcwd() yields the actual path on the machine ("D:\wamp\www" etc. in my case, using WAMP on Windows 10, I know, it's not ideal).

Is there any way to generalise this statement so that I don't need two separate paths concatenations? Am I doing this all wrong?

Answer 1

You do need two because one is a path and the other a URL. But it could be a bit more DRY.

This answer makes use of a handy constant defined in index.php - FCPATH. It is the path to the front controller (index.php) directory. Using the constant will make the code more portable, less error prone.

$doc_location = "public/mi-corpus/" . $handle . "/file.pdf";
$object_src = base_url($doc_location);
$ocr_src = FCPATH.$doc_location;