https://community.squareup.com/t5/Archived-Discussions-Read-Only/Php-API-custom-code-problem/m-p/37851#M94539 <P>Exception when calling CheckoutApi-&gt;createCheckout: [HTTP/1.1 400 Bad Request] {"errors":[{"category":"INVALID_REQUEST_ERROR","code":"VALUE_EMPTY","detail":"Field must not be blank","field":"idempotency_key"}]}</P> Mon, 08 May 2017 08:31:16 GMT shafqat 2017-05-08T08:31:16Z https://community.squareup.com/t5/Archived-Discussions-Read-Only/Php-API-custom-code-problem/m-p/37851#M94539 <P>Exception when calling CheckoutApi-&gt;createCheckout: [HTTP/1.1 400 Bad Request] {"errors":[{"category":"INVALID_REQUEST_ERROR","code":"VALUE_EMPTY","detail":"Field must not be blank","field":"idempotency_key"}]}</P> Mon, 08 May 2017 08:31:16 GMT https://community.squareup.com/t5/Archived-Discussions-Read-Only/Php-API-custom-code-problem/m-p/37851#M94539 shafqat 2017-05-08T08:31:16Z https://community.squareup.com/t5/Archived-Discussions-Read-Only/Php-API-custom-code-problem/m-p/37890#M94540 <P>That error comes when you leave the idempotency_key field blank in your request. See here for more info: <A href="https://docs.connect.squareup.com/api/connect/v2/?q=idempotency#idempotencykeys" target="_blank">https://docs.connect.squareup.com/api/connect/v2/?q=idempotency#idempotencykeys</A></P> Mon, 08 May 2017 22:39:50 GMT https://community.squareup.com/t5/Archived-Discussions-Read-Only/Php-API-custom-code-problem/m-p/37890#M94540 tristansokol 2017-05-08T22:39:50Z