Question

How can I get the input filename in mapper using php?

Answer 1

As mentioned here, for php the template for map-reduce is :

01  function map ($filename, $content) {
02      foreach (explode('', $content) as $word) {
03          collect($word, 1);
04      }
05  }
06   
07  function reduce($word, $values) {
08      $numWordCount = 0;
09   
10      foreach ($values as $value) {
11          $numWordCount += $value;
12      }
13   
14      collect($word, $numWordCount);

Now, can’t the value of $filename be printed inside a php function ?