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yaml_parse

(PECL yaml >= 0.4.0)

yaml_parseParse a YAML stream

Description

yaml_parse(
    string $input,
    int $pos = 0,
    int &$ndocs = ?,
    array $callbacks = null
): mixed

Convert all or part of a YAML document stream to a PHP variable.

Parameters

input

The string to parse as a YAML document stream.

pos

Document to extract from stream (-1 for all documents, 0 for first document, ...).

ndocs

If ndocs is provided, then it is filled with the number of documents found in stream.

callbacks

Content handlers for YAML nodes. Associative array of YAML tag => callable mappings. See parse callbacks for more details.

Return Values

Returns the value encoded in input in appropriate PHP type or false on failure. If pos is -1 an array will be returned with one entry for each document found in the stream.

Examples

Example #1 yaml_parse() example

<?php
$yaml
= <<<EOD
---
invoice: 34843
date: "2001-01-23"
bill-to: &id001
given: Chris
family: Dumars
address:
lines: |-
458 Walkman Dr.
Suite #292
city: Royal Oak
state: MI
postal: 48046
ship-to: *id001
product:
- sku: BL394D
quantity: 4
description: Basketball
price: 450
- sku: BL4438H
quantity: 1
description: Super Hoop
price: 2392
tax: 251.420000
total: 4443.520000
comments: Late afternoon is best. Backup contact is Nancy Billsmer @ 338-4338.
...
EOD;

$parsed = yaml_parse($yaml);
var_dump($parsed);
?>

The above example will output something similar to:

array(8) {
  ["invoice"]=>
  int(34843)
  ["date"]=>
  string(10) "2001-01-23"
  ["bill-to"]=>
  &array(3) {
    ["given"]=>
    string(5) "Chris"
    ["family"]=>
    string(6) "Dumars"
    ["address"]=>
    array(4) {
      ["lines"]=>
      string(34) "458 Walkman Dr.
        Suite #292"
      ["city"]=>
      string(9) "Royal Oak"
      ["state"]=>
      string(2) "MI"
      ["postal"]=>
      int(48046)
    }
  }
  ["ship-to"]=>
  &array(3) {
    ["given"]=>
    string(5) "Chris"
    ["family"]=>
    string(6) "Dumars"
    ["address"]=>
    array(4) {
      ["lines"]=>
      string(34) "458 Walkman Dr.
        Suite #292"
      ["city"]=>
      string(9) "Royal Oak"
      ["state"]=>
      string(2) "MI"
      ["postal"]=>
      int(48046)
    }
  }
  ["product"]=>
  array(2) {
    [0]=>
    array(4) {
      ["sku"]=>
      string(6) "BL394D"
      ["quantity"]=>
      int(4)
      ["description"]=>
      string(10) "Basketball"
      ["price"]=>
      int(450)
    }
    [1]=>
    array(4) {
      ["sku"]=>
      string(7) "BL4438H"
      ["quantity"]=>
      int(1)
      ["description"]=>
      string(10) "Super Hoop"
      ["price"]=>
      int(2392)
    }
  }
  ["tax"]=>
  float(251.42)
  ["total"]=>
  float(4443.52)
  ["comments"]=>
  string(68) "Late afternoon is best. Backup contact is Nancy Billsmer @ 338-4338."
}

Notes

Warning

Processing untrusted user input with yaml_parse() is dangerous if the use of unserialize() is enabled for nodes using the !php/object tag. This behavior can be disabled by using the yaml.decode_php ini setting.

See Also

add a note

User Contributed Notes 3 notes

up
6
Zalmoksis
5 years ago
It seams the YAML standard version here is the 1.1 and not the (1.2 released in 2009), so all of the following values: y, Y, yes, Yes, YES, n, N, no, No, NO, true, True, TRUE, false, False, FALSE, on, On, ON, off, Off, OFF are confusingly at times interpreted as booleans.
up
6
alpacagm at gmail dot com
12 years ago
Simple usage example of interpreting custom tags:
<?php
$data
=
"#yaml
---
data: !mytag bar test
...
"
;

function
callback($value){
return
str_replace('bar','baz',$value);
}
$cnt;
$array=yaml_parse($data,0,$cnt,array('!mytag'=>'callback'));

print_r($array['data']);
?>
output:
Array
(
[data] => baz test
)
note, there is a related bug in version 1.0.1 (see tracker)
up
1
laura dot dean at mooneleaf dot com
8 years ago
When entering the string through a form, I had to first use utf8_decode on the input before using yaml_parse or else I got a cryptic error message --

Warning: yaml_parse(): reading error encountered during parsing: control characters are not allowed (line 1, column 1)

-- even though the special character was buried deep in the file.
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