Smarty Forum Index Smarty
The discussions here are for Smarty, a template engine for the PHP programming language.

json encode - pass multiple bitmask constants for formatting

 
Post new topic   Reply to topic    Smarty Forum Index -> General
View previous topic :: View next topic  
Author Message
andrewFountain
Smarty n00b


Joined: 31 Aug 2018
Posts: 3

PostPosted: Wed Apr 24, 2019 5:10 am    Post subject: json encode - pass multiple bitmask constants for formatting Reply with quote

Hi,

I'm wondering if there is any way to pass multiple bitmask constants when formatting using json_encode in a template.

The json structure has been assigned to the page as an associative array that cannot easily be converted in the php side of the application, so I'm using json_encode inside the template.

Unfortunately as the bitmask uses pipes to separate the constants in php which is syntax for a function in smarty eg.

PHP
this syntax will work in php
Code:
$json = [
  'one' => 1,
  'arr' => [
    'two' => 2
  ]
];
echo json_encode($json, JSON_PRETTY_PRINT | JSON_UNESCAPE_SLASHES);



SMARTY
this syntax won't work in smarty as the `|` "pipe" is used to call a function on the value
Code:
{$json = [
  'one' => 1,
  'arr' => [
    'two' => 2
  ]
]}
{$json|json_encode:$smarty.const.JSON_PRETTY_PRINT|$smarty.const.JSON_PRETTY_PRINT}


I have tried to pass the constants as arguments and as items in an array but neither solution worked.
Code:
{$json = [
  'one' => 1,
  'arr' => [
    'two' => 2
  ]
]}
{$json|json_encode:$smarty.const.JSON_PRETTY_PRINT:$smarty.const.JSON_PRETTY_PRINT}

Code:
{$json = [
  'one' => 1,
  'arr' => [
    'two' => 2
  ]
]}
{$json|json_encode:[$smarty.const.JSON_PRETTY_PRINT, $smarty.const.JSON_PRETTY_PRINT]}


Is there any way that I can pass more than one constant to json_encode?

** note **
We have disabled the {php}{/php} tag as it's a security concern for us to allow integrators to execute unknown php in their templates.


Edit: would it be better to create a modifier to perform a json encode.
Code:
function smarty_modifier_json($json, ...$constants) {

  $jsonConstants = [
    'JSON_PRETTY_PRINT' => JSON_PRETTY_PRINT,
    'JSON_UNESCAPE_SLASHES' => JSON_UNESCAPE_SLASHES,
    // add more constants here
  ];

  $validConstants = array_filter($constants, function($constant) {
    return !empty($jsonConstants[$constant]);
  });

  $cominedConstants = array_reduce($validConstants , function($acc, $constant) {
    return $acc | $constant;
  }, 0);

  return json_encode($json, $cominedConstants);
}


Code:
{$json|json:'JSON_PRETTY_PRINT':'JSON_UNESAPE_SLASHES'}



Cheers,

Andrew[/code]
Back to top
View user's profile Send private message
AnrDaemon
Administrator


Joined: 03 Dec 2012
Posts: 1532

PostPosted: Wed Apr 24, 2019 7:15 pm    Post subject: Reply with quote

Use braces.
But I have a better question: Why do you use Smarty at all for JSON encoding?
Back to top
View user's profile Send private message
andrewFountain
Smarty n00b


Joined: 31 Aug 2018
Posts: 3

PostPosted: Fri Apr 26, 2019 4:38 am    Post subject: Reply with quote

Because it's takes a long time to get anything changed in the back end and we have so many modules without any underlying consistent framework so to add a new method to anything takes a very long time, and this gives me full control of structuring my json before consuming it.

The answer is actually very simple. You can just add the different bitwise constants as that is all the Or operator actually does.

Code:
JSON_UNESCAPED_SLASHES | JSON_PRETTY_PRINT === 196
JSON_UNESCAPED_SLASHES + JSON_PRETTY_PRINT) === 196
196 === 0b11000100


Code:
{$json|json_encode:(
     $smarty.const.JSON_UNESCAPED_SLASHES
   + $smarty.const.JSON_PRETTY_PRINT
)}
Back to top
View user's profile Send private message
AnrDaemon
Administrator


Joined: 03 Dec 2012
Posts: 1532

PostPosted: Sat Apr 27, 2019 5:46 pm    Post subject: Reply with quote

That's only true if operands are single different bits.
But try to compare
Code:
JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_SLASHES

versus
Code:
JSON_UNESCAPED_SLASHES + JSON_UNESCAPED_SLASHES
Back to top
View user's profile Send private message
AnrDaemon
Administrator


Joined: 03 Dec 2012
Posts: 1532

PostPosted: Sat Apr 27, 2019 7:29 pm    Post subject: Reply with quote

After trying your issue in sandbox, I understand the origin better.
Smarty uses "|" as filter separator, and there seems to be no way to escape it.
Your only options is to set encoding options from PHP as a variable or supply them numerically in template.
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Smarty Forum Index -> General All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group
Protected by Anti-Spam ACP