Deadline expired before operation could complete. For operations
that change the state of the system, this error may be returned
even if the operation has completed successfully. For example, a
successful response from a server could have been delayed long
enough for the deadline to expire.
Operation was rejected because the system is not in a state
required for the operation’s execution. For example, directory
to be deleted may be non-empty, an rmdir operation is applied to
a non-directory, etc.
Client specified an invalid argument. Note that this differs
from FAILED_PRECONDITION. INVALID_ARGUMENT indicates arguments
that are problematic regardless of the state of the system
(e.g., a malformed file name).
The caller does not have permission to execute the specified
operation. PERMISSION_DENIED must not be used for rejections
caused by exhausting some resource (use RESOURCE_EXHAUSTED
instead for those errors). PERMISSION_DENIED must not be
used if the caller can not be identified (use UNAUTHENTICATED
instead for those errors).
The service is currently unavailable. This is a most likely a
transient condition and may be corrected by retrying with
a backoff. Note that it is not always safe to retry non-idempotent
operations.
Unknown error. An example of where this error may be returned is
if a Status value received from another address space belongs to
an error-space that is not known in this address space. Also
errors raised by APIs that do not return enough error information
may be converted to this error.