Creating a translation class with PHP associative array - php

Question

I have written a very simple translation class that is supposed to return the meaning associated with the phrase that I give to it. Under the hood, it loads translations from a csv upon construction into an associative array. Upon translation request, it checks the array. If the phrase is there as a key in the array, returns its value, which is its translation. If the phrase does not exist as a key, it loads the array from the file again (as there might be new translations), checks for the key again. If it does not find the key again, the phrase will be returned as is.
<?php
class Translate{
function __construct() {
$this->loadTranslations();
}
public function get($message, $lang = "de"): string{
if(key_exists($message, self::$de)){
return self::$de[$message];
}
else {
//Load translations again
$this->loadTranslations();
if(isset(self::$de[$message])){
return self::$de[$message];
}
else {
return $message;
}
}
}
protected static $de = [];
protected function loadTranslations() {
$file = fopen(__DIR__ . "/../data/de.csv", "r");
if($file){
while($line = fgets($file)){
$en_de = explode(":", $line);
self::$de[array_shift($en_de)] = array_shift($en_de);
}
}
fclose($file);
}
}
$t = new Translate();
echo $t->get("Hello") . PHP_EOL;
Content of de.csv is like this:
"Hi": "Hallo"
"Hello": "Hallo"
The problem is when asked for a translation, the class always returns the given phrase. When I dump the array, the phrase is there as a key, but there is no success in accessing $array[$phrase] as PHP does not find the key in the array!

Answer 1

The problem is that in your CSV file, you have quotes round the text, so although Hello exists, it's actually stored in the translation array as "Hello" so will not match.
You could either redo your translation file to not have the quotes, or you could use the functionality of fgetcsv() to read it and strip out any surrounding quotes (use : as the separator)...
protected function loadTranslations() {
$file = fopen(__DIR__ . "/a.csv", "r");
if($file){
while([$key, $trans] = fgetcsv($file, null, ":", '"')){
self::$de[$key] = $trans;
}
}
fclose($file);
}
Just looking at the code to fetch the translation, you could shorten it. First check that the translations are loaded, then return the translation - using ?? to say if it's not found, then return the original message...
public function get($message, $lang = "de"): string{
if(!isset(self::$de)){
$this->loadTranslations();
}
return self::$de[$message] ?? $message;
}

Answer 2

Your csv looks more like json to me.
I'd probably adjust the file to be json permanently, but until then, just convert it into a json string manually, then decode it to create your key-value pairs.
self::$de = json_decode(
'{' . implode(',', file(__DIR__ . "/a.csv")) . '}',
true
);
In other words, make all of your language files valid json. This way you can instantly cal json_decode() on the entire file contents and the array is ready. Keeping your file in the current format means individually isolating each line of text in the file and calling a function to parse it -- this is waaaaay too much work to be done each time.
Please consistently write your class variables at the top of your class.
$de should not be a variable name -- I am assuming it is referring to a specific language. $lang() should be used to specify the user's desired language and search for the appropriate filename.
Edit:
I really can't overstate how beneficial it is to convert your files to valid json -- it just makes everything cleaner. Here is a re-write of your code. I don't agree with the use of a static class variable, nor the constructor that that loads a language without know what is going to be used. And as previously mentioned there should be no variable that refers to a specific language ($de). The class variable $translations should be an associative array containing subarrays so that you can permanently load and access multiple translations at the same time.
Untested suggestion:
class Translate{
protected $translations = [];
protected function loadTranslations($lang)
{
$filePath = __DIR__ . '/' . $lang . '.json';
if (file_exists($filePath)) {
$this->translations[$lang] = json_decode(file_get_contents($filePath), true);
}
}
public function get($message, $lang = "de"): string
{
if (!isset($this->translations[$lang])) {
$this->loadTranslations($lang);
}
return $this->translations[$lang][$message] ?? $message;
}
// e.g. $newTrans = ['Good Day' => 'Guten Tag', ...]
public function set($lang, $newTrans)
{
if (!isset($this->translations[$lang])) {
$this->loadTranslations($lang);
}
$this->translations[$lang] += $newTrans; // insert or overwrite key-value pair(s)
file_put_contents(__DIR__ . '/' . $lang . '.json', json_encode($this->translations[$lang])); // commit to file
}
}
$t = new Translate();
echo $t->get("Hello") . PHP_EOL;