Unable to call existing internal routes in a Slim API

I am currently developing a RESTful API to maintain a number of databases. Ideally I should be able to call my APIs routes from another route within my application, correct?

I've tried using subRequest in order to call an existing route to no avail. All I get is the following while executing my route in Postman:

<html>
    <head>
        <meta http-equiv='Content-Type' content='text/html; charset=utf-8'>
        <title>Slim Application Error</title>
        <style>body{margin:0;padding:30px;font:12px/1.5 Helvetica,Arial,Verdana,sans-serif;}h1{margin:0;font-size:48px;font-weight:normal;line-height:48px;}strong{display:inline-block;width:65px;}</style>
    </head>
    <body>
        <h1>Slim Application Error</h1>
        <p>A website error has occurred. Sorry for the temporary inconvenience.</p>
    </body>
</html>

Below are my companies.php API routes to get all companies in a table and to put a new company into the companies table.

<?php
use \Psr\Http\Message\ServerRequestInterface as Request;
use \Psr\Http\Message\ResponseInterface as Response;

// Get all companies
$app->get('/companies', function(Request $request, Response $response) {
  $sql = "SELECT * FROM companies";

  try {
    // Get DB Object
    $db = new db();
    // Connect
    $db = $db->connect();

    $stmt = $db->query($sql);
    $companies = $stmt->fetchAll(PDO::FETCH_OBJ);
    $db = null;

    echo '{"data":' . json_encode($companies) . '}';
  } catch(PDOException $e) {
    echo '{"error": { "text":' . $e->getMessage() . '}}';
  }
});

// Add new company to companies table
$app->put('/new/company/{companyName}', function(Request $request, Response $response) {
  $newCompany = $request->getAttribute('companyName');

  $insert_sql = "INSERT INTO companies (company_name) VALUE (:newCompany)";

  try {
    $db = new db();
    $db = $db->connect();

    $insert_stmt = $db->prepare($insert_sql);
    $newCompany = str_replace("'", "", $newCompany);
    $insert_stmt->bindParam(':newCompany', $newCompany);
    $insert_stmt->execute();

    $newID = $db->lastInsertId();
    $db = null;

    echo '{"notice": {"text": "New Company Added (cid: '.$newID.')"}';
  } catch(PDOException $e) {
    echo '{"error": { "text":' . $e->getMessage() . '}}';
  }
});

Within a different route, sites.php, I would like to run the PUT->'/new/company' route. So, somewhere within sites.php I place the following:

  $destinationComp = "myNewCompany";
  $res = $this->subRequest('PUT', '/new/company/' . $destinationComp);
  echo $res;

I would expect my output to be the same as if I made a PUT request manually from Postman, instead of the error listed in the first code-section.

Furthermore, I've tried modifying my route call to include use ($app) in hopes of making a regular request through the $app variable rather than $this, is case $this wasn't working. Which looked like:

$app->put('/new/site/{sourceCompany}/{sourceProperty}/{destinationCompany}/{destinationProperty}', function(Request $request, Response $response) use ($app) {
   $destinationComp = "myNewCompany";
   $res = $app->put("/new/company/$destinationComp");
   echo $res;

   //More code to follow...
}

Only to receive the same error message in Postman upon execution.

Any suggestions?

Solution

You are attempting to call the subRequest method on the Container class, when it should be the App class.

inside route closure, $this is bound to the instance of Slim\Container - Slim docs

Reference the $app var instead, inject it with use keyword. In addition, return the response object instead of doing echo:

return $app->subRequest('PUT', '/new/company/' . $destinationComp);