Wordpress PHP Fatal Error with Openshift - php

Question

When I try to access the plugins or themes section of my wordpress site from the admin panel I am presented with a blank screen. When I run the logs I get the following error:
Navigating to wp-admin/plugins.php:
PHP Fatal error: Call to undefined function wp_json_encode() in /var/lib/openshift/{userID}/app-root/data/current/wp-includes/update.php on line 277
Navigating to wp-admin/themes.php:
PHP Fatal error: Call to undefined function wp_json_encode() in /var/lib/openshift/{userID}/app-root/data/current/wp-includes/update.php on line 440
Solutions online indicated that I should re-add the function, or re-install Wordpress. Without access to the core files, I downloaded a local repository of the application (but noticed it did not contain any of the plugins or themes I had uploaded via the admin interface).
I extracted a plugin and theme (placing them in the respective directories) then pushed the changes to production in the hopes that it would extract and re-install an updated version of wordpress. I then restarted the app.
The error still persists and I can not validate if the plugin or theme I uploaded were installed. Is there a way to refresh or reinstall a wordpress instance on Openshift?
I'm wondering how I can fix this issue without creating a new gear and migrating my data via the database. Note: Front end is working fine.
Version of Wordpress: 4.1.1

Answer 1

I ended up connecting to the app via SFTP and modified the file the following directly
/var/lib/openshift/{userID}/app-root/data/current/wp-includes/functions.php
and added the following function:
function wp_json_encode( $data, $options = 0, $depth = 512 ) {
/*
* json_encode() has had extra params added over the years.
* $options was added in 5.3, and $depth in 5.5.
* We need to make sure we call it with the correct arguments.
*/
if ( version_compare( PHP_VERSION, '5.5', '>=' ) ) {
$args = array( $data, $options, $depth );
} elseif ( version_compare( PHP_VERSION, '5.3', '>=' ) ) {
$args = array( $data, $options );
} else {
$args = array( $data );
}
$json = call_user_func_array( 'json_encode', $args );
// If json_encode() was successful, no need to do more sanity checking.
// ... unless we're in an old version of PHP, and json_encode() returned
// a string containing 'null'. Then we need to do more sanity checking.
if ( false !== $json && ( version_compare( PHP_VERSION, '5.5', '>=' ) || false === strpos( $json, 'null' ) ) ) {
return $json;
}
try {
$args[0] = _wp_json_sanity_check( $data, $depth );
} catch ( Exception $e ) {
return false;
}
return call_user_func_array( 'json_encode', $args );
}
Ref: https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-wp_json_encode-in