<?php
/**
* Serialize PHP values and objects into a human-readable format, useful for
* displaying errors.
*
* @task print Printing PHP Values
* @task internal Internals
*/
final class PhutilReadableSerializer extends Phobject {
/* -( Printing PHP Values )------------------------------------------------ */
/**
* Given a value, makes the best attempt at returning a string representation
* of that value suitable for printing. This method returns a //complete//
* representation of the value; use @{method:printShort} or
* @{method:printShallow} to summarize values.
*
* @param wild Any value.
* @return string Human-readable representation of the value.
* @task print
*/
public static function printableValue($value) {
if ($value === null) {
return 'null';
} else if ($value === false) {
return 'false';
} else if ($value === true) {
return 'true';
} else if (is_float($value) && (int)$value == $value) {
return $value.'.0';
} else if (is_string($value)) {
return "'".$value."'";
} else {
return print_r($value, true);
}
}
/**
* Print a concise, human readable representation of a value.
*
* @param wild Any value.
* @return string Human-readable short representation of the value.
* @task print
*/
public static function printShort($value) {
if (is_object($value)) {
return 'Object '.get_class($value);
} else if (is_array($value)) {
$str = 'Array ';
if ($value) {
if (count($value) > 1) {
$str .= 'of size '.count($value).' starting with: ';
}
reset($value); // Prevent key() from giving warning message in HPHP.
$str .= '{ '.self::printShort(key($value)).' => '.
self::printShort(head($value)).' }';
}
return $str;
} else {
// NOTE: Avoid PhutilUTF8StringTruncator here since the data may not be
// UTF8 anyway, it's slow for large inputs, and it might not be loaded
// yet.
$limit = 1024;
$str = self::printableValue($value);
if (strlen($str) > $limit) {
if (is_string($value)) {
$str = "'".substr($str, 1, $limit)."...'";
} else {
$str = substr($str, 0, $limit).'...';
}
}
return $str;
}
}
/**
* Dump some debug output about an object's members without the
* potential recursive explosion of verbosity that comes with `print_r()`.
*
* To print any number of member variables, pass null for `$max_members`.
*
* @param wild Any value.
* @param int Maximum depth to print for nested arrays and objects.
* @param int Maximum number of values to print at each level.
* @return string Human-readable shallow representation of the value.
* @task print
*/
public static function printShallow(
$value,
$max_depth = 2,
$max_members = 25) {
return self::printShallowRecursive($value, $max_depth, $max_members, 0, '');
}
/* -( Internals )---------------------------------------------------------- */
/**
* Implementation for @{method:printShallow}.
*
* @param wild Any value.
* @param int Maximum depth to print for nested arrays and objects.
* @param int Maximum number of values to print at each level.
* @param int Current depth.
* @param string Indentation string.
* @return string Human-readable shallow representation of the value.
* @task internal
*/
private static function printShallowRecursive(
$value,
$max_depth,
$max_members,
$depth,
$indent) {
if (!is_object($value) && !is_array($value)) {
return self::addIndentation(self::printableValue($value), $indent, 1);
}
$ret = '';
if (is_object($value)) {
$ret = get_class($value)."\nwith members ";
$value = array_filter(@(array)$value);
// Remove null characters that magically appear around keys for
// member variables of parent classes.
$transformed = array();
foreach ($value as $key => $x) {
$transformed[str_replace("\0", ' ', $key)] = $x;
}
$value = $transformed;
}
if ($max_members !== null) {
$value = array_slice($value, 0, $max_members, $preserve_keys = true);
}
$shallow = array();
if ($depth < $max_depth) {
foreach ($value as $k => $v) {
$shallow[$k] = self::printShallowRecursive(
$v,
$max_depth,
$max_members,
$depth + 1,
' ');
}
} else {
foreach ($value as $k => $v) {
// Extra indentation is for empty arrays, because they wrap on multiple
// lines and lookup stupid without the extra indentation
$shallow[$k] = self::addIndentation(self::printShort($v), $indent, 1);
}
}
return self::addIndentation($ret.print_r($shallow, true), $indent, 1);
}
/**
* Adds indentation to the beginning of every line starting from
* `$first_line`.
*
* @param string Printed value.
* @param string String to indent with.
* @param int Index of first line to indent.
* @return string
* @task internal
*/
private static function addIndentation($value, $indent, $first_line) {
$lines = explode("\n", $value);
$out = array();
foreach ($lines as $index => $line) {
$out[] = $index >= $first_line ? $indent.$line : $line;
}
return implode("\n", $out);
}
}