I'm seeing the following error when trying to edit or create a resource:

  "error": "std::runtime_error",
  "message": "Invalid \\u escape sequence"


There must be a more than two byte character in a string endpoint returns to you, examples:

  • some Japanese/Chinese characters (mostly 3 and 4 bytes)
  • some currency signs: € sign (0xE2, 0x82, 0xAC)

For example you during creation of a customer you may send balance property:

"balance": "40.399,64 €"

Creation fails with "Invalid \\u escape sequence" error, the endpoint returned 200 OK response to the contoller along with payload mirroring the one that was sent however the balance property is different:

"balance": "40.399,64 \u20ac"

The cause is that in PHP prior to 5.4 json_encode() automatically escaped unicode, in PHP 5.4 JSON_UNESCAPED_UNICODE was introduced:


Upgrade PHP on endpoint to 5.4 and aps-php-runtime >= 2.0-340

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