PHP: fopen error handling - php

Question

I do fetch a file with
$fp = fopen('uploads/Team/img/'.$team_id.'.png', "rb");
$str = stream_get_contents($fp);
fclose($fp);
and then the method gives it back as image. But when fopen() fails, because the file did not exists, it throws an error:
[{"message":"Warning: fopen(uploads\/Team\/img\/1.png): failed to open stream: No such file or directory in C:\...
This is coming back as json, obviously.
The Question is now: How can i catch the error and prevent the method from throwing this error directly to the client?

Answer 1

You should first test the existence of a file by file_exists().
try
{
$fileName = 'uploads/Team/img/'.$team_id.'.png';
if ( !file_exists($fileName) ) {
throw new Exception('File not found.');
}
$fp = fopen($fileName, "rb");
if ( !$fp ) {
throw new Exception('File open failed.');
}
$str = stream_get_contents($fp);
fclose($fp);
// send success JSON
} catch ( Exception $e ) {
// send error message if you can
}
or simple solution without exceptions:
$fileName = 'uploads/Team/img/'.$team_id.'.png';
if ( file_exists($fileName) && ($fp = fopen($fileName, "rb"))!==false ) {
$str = stream_get_contents($fp);
fclose($fp);
// send success JSON
}
else
{
// send error message if you can
}

Answer 2

You can use the file_exists() function before calling fopen().
if(file_exists('uploads/Team/img/'.$team_id.'.png')
{
$fp = fopen('uploads/Team/img/'.$team_id.'.png', "rb");
$str = stream_get_contents($fp);
fclose($fp);
}

Answer 3

[{"message":"Warning: fopen(uploads\/Team\/img\/1.png): failed to open stream: No such file or directory in C:\...
the error is clear: you've put the wrong directory, you can try what you whant but it'll not work. you can make it work with this:
take your file and put it in the same folder of your php file
(you'll be able to move it after don't worry, it's about your error)
or on a folder "higher" of your script (just not outside of your www
folder)
change the fopen to ('./$team_id.'png',"rb");
rerun your script file
don't forget this : you can't access a file that is'nt in your "www" folder
(he doesn't found your file because he give you her name: the name come from the $team_id variable)

Answer 4

Generically - This is probably the best way to do file-io in php (as mentioned by #Cendak here)
$fileName = 'uploads/Team/img/'.$team_id.'.png';
if ( file_exists($fileName) && ($fp = fopen($fileName, "rb"))!==false ){
$str = stream_get_contents($fp);
fclose($fp);
// send success JSON
}else{
// send an error message if you can
}
But it does not work with PHP 7.3, these modifications do,
if(file_exists($filename) && ($fp = fopen($filename,"r") !== false)){
$fp = fopen($filename,"r");
$filedata = fread($fp,filesize($filename));
fclose($fp);
}else{
$filedata = "default-string";
}