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As PHP version 5.5 is no longer supported by the community, we strongly recommend new apps use the PHP 7+ runtime.




Thrown when there is a general failure using the AppIdentityService.


The AppIdentityService allows you to sign arbitrary byte array using per app private key maintained by App Engine. You can also retrieve a list of public certificates which can be used to verify the signature.


PublicCertificate contains an X509 public certificate in PEM format and a string which is used to identify this certificate.