Issues

ZF2-10: iterating over a Zend_Config

Description

There are two xml-files.


<?xml version="1.0" encoding="utf-8" ?>

and


<?xml version="1.0" encoding="utf-8" ?>

and the sample code:


<?php
    require_once 'Zend/Config.php';
    require_once 'Zend/Config/Xml.php';
    
    $config = new Zend_config_xml('/path/to/config.xml');
    foreach ($config->files->file as $value)
        echo 'id: '.$value->id.'
location: '. htmlspecialchars($value->location).''; ?>

If the {{/path/to/config.xml}} to substitute {{config1.xml}}, then everything works correctly. But if you substitute {{config2.xml}} error


Notice: Trying to get property of non-object in D:\www\index.php on line 7

How can I iterate all items {{file}}, if their number is not known in advance (one or more than one)?

Comments

Can't fix at Zend_Config level. Workaround is to use UTF8 files without a BOM marker.

(Closed wrong issue!)

I'm not sure there's any way to resolve this issue due to the other than creating a dummy key to force an array:


<?xml version="1.0" encoding="utf-8" ?>

might work, but don't forget to test for id being null.

This issue also exists when using the toArray() method of Zend_Config. The problem is that you just want the array to ALWAYS have the same layout. Config files tent to grow and be extended, just like XML files.

In my opinion the Zend_Config API should work the same as the of SimpleXml, here two extended examples and their output: h2. Using SimpleXML


<?php
// Files with single file element
$xmlString1 = <<indexindex.html
XML;

// Files with multiple file elements
$xmlString2 = <<indexindex.htmlindex2index2.html
XML;

echo "Files with single file element, looping files->file:\n";
$xml1 = new SimpleXMLElement($xmlString1);
foreach ($xml1->files->file as $file) {
    var_dump($file);
    printf("%s: %s\n", 'id', $file->id);
    printf("%s: %s\n", 'localtion', $file->location);
}
echo "Files with single file element, looping files->file->id:\n";
foreach ($xml1->files->file->id as $id) {
    var_dump($id);
    printf("%s: %s\n", 'id', $id);
}

echo "Files with multiple file elements, looping files->file:\n";
$xml2 = new SimpleXMLElement($xmlString2);
foreach ($xml2->files->file as $file) {
    var_dump($file);
    printf("%s: %s\n", 'id', $file->id);
    printf("%s: %s\n", 'localtion', $file->location);
}
echo "Files with multiple file elements, looping files->file->id:\n";
foreach ($xml2->files->file->id as $id) {
    var_dump($id);
    printf("%s: %s\n", 'id', $id);
}
Files with single file element, looping files->file:
object(SimpleXMLElement)#3 (2) {
  ["id"]=>
  string(5) "index"
  ["location"]=>
  string(10) "index.html"
}
id: index
localtion: index.html
Files with single file element, looping files->file->id:
object(SimpleXMLElement)#2 (1) {
  [0]=>
  string(5) "index"
}
id: index
Files with multiple file elements, looping files->file:
object(SimpleXMLElement)#6 (2) {
  ["id"]=>
  string(5) "index"
  ["location"]=>
  string(10) "index.html"
}
id: index
localtion: index.html
object(SimpleXMLElement)#3 (2) {
  ["id"]=>
  string(6) "index2"
  ["location"]=>
  string(11) "index2.html"
}
id: index2
localtion: index2.html
Files with multiple file elements, looping files->file->id:
object(SimpleXMLElement)#4 (1) {
  [0]=>
  string(5) "index"
}
id: index

h2. Using Zend_Config_Xml possibly a global Zend_Config or other Zend_Config* types issue, I have not tested that_


<?php
set_include_path(
    get_include_path()
    . PATH_SEPARATOR . 'library/'
);

require_once 'Zend/Loader/Autoloader.php';
Zend_Loader_Autoloader::getInstance()->setFallbackAutoloader(true);

// Files with single file element
$xmlString1 = <<indexindex.html
XML;

// Files with multiple file elements
$xmlString2 = <<indexindex.htmlindex2index2.html
XML;

echo "Files with single file element, looping files->file:\n";
$xml1 = new Zend_Config_Xml($xmlString1);
foreach ($xml1->files->file as $file) {
    var_dump($file);
    printf("%s: %s\n", 'id', $file->id);
    printf("%s: %s\n", 'localtion', $file->location);
}
echo "Files with single file element, looping files->file->id:\n";
foreach ($xml1->files->file->id as $id) {
    var_dump($id);
    printf("%s: %s\n", 'id', $id);
}

echo "Files with multiple file elements, looping files->file:\n";
$xml2 = new Zend_Config_Xml($xmlString2);
foreach ($xml2->files->file as $file) {
    var_dump($file);
    printf("%s: %s\n", 'id', $file->id);
    printf("%s: %s\n", 'localtion', $file->location);
}
echo "Files with multiple file elements, looping files->file->id:\n";
foreach ($xml2->files->file->id as $id) {
    var_dump($id);
    printf("%s: %s\n", 'id', $id);
}
Files with single file element, looping files->file:
string(5) "index"

Notice: Trying to get property of non-object in D:\www\htdocs\dev\config\config.php on line 44
id:
Notice: Trying to get property of non-object in D:\www\htdocs\dev\config\config.php on line 45
localtion: string(10) "index.html"
Notice: Trying to get property of non-object in D:\www\htdocs\dev\config\config.php on line 44
id:
Notice: Trying to get property of non-object in D:\www\htdocs\dev\config\config.php on line 45
localtion: Files with single file element, looping files->file->id:
Warning: Invalid argument supplied for foreach() in D:\www\htdocs\dev\config\config.php on line 48
Files with multiple file elements, looping files->file: object(Zend_Config)#9 (8) { ["_allowModifications:protected"]=> bool(false) ["_index:protected"]=> int(0) ["_count:protected"]=> int(2) ["_data:protected"]=> array(2) { ["id"]=> string(5) "index" ["location"]=> string(10) "index.html" } ["_skipNextIteration:protected"]=> NULL ["_loadedSection:protected"]=> NULL ["_extends:protected"]=> array(0) { } ["_loadFileErrorStr:protected"]=> NULL } id: index localtion: index.html object(Zend_Config)#11 (8) { ["_allowModifications:protected"]=> bool(false) ["_index:protected"]=> int(0) ["_count:protected"]=> int(2) ["_data:protected"]=> array(2) { ["id"]=> string(6) "index2" ["location"]=> string(11) "index2.html" } ["_skipNextIteration:protected"]=> NULL ["_loadedSection:protected"]=> NULL ["_extends:protected"]=> array(0) { } ["_loadFileErrorStr:protected"]=> NULL } id: index2 localtion: index2.html Files with multiple file elements, looping files->file->id:
Warning: Invalid argument supplied for foreach() in D:\www\htdocs\dev\config\config.php on line 61

{color:red}note:{color} Output rendered with PHP in error_reporting mode = E_ALL | E_STRICT

I'm open to ideas on how to solve this without breaking backwards compatibility.

You could just do:


$files = (isset($files->file[0]) ? $files->file : array($files->file));

And then just work with the $files variable as array. That works pretty well.

Although this is fixable, fixing it will always break backwards compatibility. When a developer knows there's only 1 item, code such as this will be broken :


echo $config->files->file['id'];

Because it will in fact have to become :


$file = $config->files->file->toArray();
echo $file[0]['id'];

I would advise against modifying this for ZF 1.x - not sure how this will be handled in ZF 2, but introducing this backwards incompatibility is not a good idea in any case...

The only other option is to modify just the magic/fluent notation, but that will make things complicated and will cause inconsistency between fluent notation and array notation, which should be avoided.

One idea I have had is to introduce a children() method that always returns an iterator/array regardless of whether there is is one or many children:


$files = $config->files->children();
foreach ($files as $file) {
    echo $file->id;
}

Thoughts on this approach?

Moved to ZF2 as likely to involve a BC break.

Approaching RC1, we need to decide if anything is going to be done about this.

This issue has been closed on Jira and moved to GitHub for issue tracking. To continue following the resolution of this issues, please visit: https://github.com/zendframework/zf2/issues/2443