Serialized custom field data is not imported correctly after being exported by the standard WordPress export/import plugin #70
Description
This is probably not a bug specific to CMS Toolkit, but I couldn't think of a better place to put it.
Example:
The milestone meta_value is stored in an array of strings:
…
"milestones": [
"Determine how much you can afford to spend on a home",
"Decide if it’s the right time to buy a new home",
"Gather your application paperwork"
],
…This data is exported to WordPress's XML format in a serialized form, like so:
…
<wp:postmeta>
<wp:meta_key>milestones</wp:meta_key>
<wp:meta_value><![CDATA[a:3:{i:0;s:52:"Determine how much you can afford to spend on a home";i:1;s:50:"Decide if it’s the right time to buy a new home ";i:2;s:34:"Gather your application paperwork ";}]]></wp:meta_value>
</wp:postmeta>
…After attempting to import into a different WordPress installation, the JSON output for the field shows:
…
"milestones": [
"a:0:{}",
"a:3:{i:0;s:52:\"Determine how much you can afford to spend on a home\";i:1;s:50:\"Decide if it’s the right time to buy a new home \";i:2;s:34:\"Gather your application paperwork \";}"
],
…For some reason, the data is not being correctly unserialized. It could be being exported incorrectly, imported incorrectly, or both.
Things we've tried:
-
Using WP-CLI to export and import the data. WP-CLI definitely doesn't export it correctly. It shows an empty serialized array:
wp:postmeta
wp:meta_keymilestones/wp:meta_key
wp:meta_value/wp:meta_value
/wp:postmeta -
Adding a
maybe_unserialize()call to the line in the import plugin's parser that sets meta values. Appears to have no effect.
I think the next step is a full step-by-step debugging of the import process.