mojo/public/mojom/base/absl_status.mojom

// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module mojo_base.mojom;

// These values come from //third_party/abseil-cpp/absl/status/status.h and
// any updates here should also be reflected there.
//
// Note: kDoNotUseReservedForFutureExpansionUseDefaultInSwitchInstead_ is excluded
// from this enum. Any user of this enum should fail if an unrecognized
// status code is used.
enum AbslStatusCode {
  // AbslStatusCode::kOk
  //
  // kOK (gRPC code "OK") does not indicate an error; this value is returned on
  // success. It is typical to check for this value before proceeding on any
  // given call across an API or RPC boundary. To check this value, use the
  // `absl::Status::ok()` member function rather than inspecting the raw code.
  kOk = 0,

  // AbslStatusCode::kCancelled
  //
  // kCancelled (gRPC code "CANCELLED") indicates the operation was cancelled,
  // typically by the caller.
  kCancelled = 1,

  // AbslStatusCode::kUnknown
  //
  // kUnknown (gRPC code "UNKNOWN") indicates an unknown error occurred. In
  // general, more specific errors should be raised, if possible. Errors raised
  // by APIs that do not return enough error information may be converted to
  // this error.
  kUnknown = 2,

  // AbslStatusCode::kInvalidArgument
  //
  // kInvalidArgument (gRPC code "INVALID_ARGUMENT") indicates the caller
  // specified an invalid argument, such as a malformed filename. Note that use
  // of such errors should be narrowly limited to indicate the invalid nature of
  // the arguments themselves. Errors with validly formed arguments that may
  // cause errors with the state of the receiving system should be denoted with
  // `kFailedPrecondition` instead.
  kInvalidArgument = 3,

  // AbslStatusCode::kDeadlineExceeded
  //
  // kDeadlineExceeded (gRPC code "DEADLINE_EXCEEDED") indicates a deadline
  // expired before the operation could complete. For operations that may change
  // state within a 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.
  kDeadlineExceeded = 4,

  // AbslStatusCode::kNotFound
  //
  // kNotFound (gRPC code "NOT_FOUND") indicates some requested entity (such as
  // a file or directory) was not found.
  //
  // `kNotFound` is useful if a request should be denied for an entire class of
  // users, such as during a gradual feature rollout or undocumented allow list.
  // If a request should be denied for specific sets of users, such as through
  // user-based access control, use `kPermissionDenied` instead.
  kNotFound = 5,

  // AbslStatusCode::kAlreadyExists
  //
  // kAlreadyExists (gRPC code "ALREADY_EXISTS") indicates that the entity a
  // caller attempted to create (such as a file or directory) is already
  // present.
  kAlreadyExists = 6,

  // AbslStatusCode::kPermissionDenied
  //
  // kPermissionDenied (gRPC code "PERMISSION_DENIED") indicates that the caller
  // does not have permission to execute the specified operation. Note that this
  // error is different than an error due to an *un*authenticated user. This
  // error code does not imply the request is valid or the requested entity
  // exists or satisfies any other pre-conditions.
  //
  // `kPermissionDenied` must not be used for rejections caused by exhausting
  // some resource. Instead, use `kResourceExhausted` for those errors.
  // `kPermissionDenied` must not be used if the caller cannot be identified.
  // Instead, use `kUnauthenticated` for those errors.
  kPermissionDenied = 7,

  // AbslStatusCode::kResourceExhausted
  //
  // kResourceExhausted (gRPC code "RESOURCE_EXHAUSTED") indicates some resource
  // has been exhausted, perhaps a per-user quota, or perhaps the entire file
  // system is out of space.
  kResourceExhausted = 8,

  // AbslStatusCode::kFailedPrecondition
  //
  // kFailedPrecondition (gRPC code "FAILED_PRECONDITION") indicates that the
  // operation was rejected because the system is not in a state required for
  // the operation's execution. For example, a directory to be deleted may be
  // non-empty, an "rmdir" operation is applied to a non-directory, etc.
  //
  // Some guidelines that may help a service implementer in deciding between
  // `kFailedPrecondition`, `kAborted`, and `kUnavailable`:
  //
  //  (a) Use `kUnavailable` if the client can retry just the failing call.
  //  (b) Use `kAborted` if the client should retry at a higher transaction
  //      level (such as when a client-specified test-and-set fails, indicating
  //      the client should restart a read-modify-write sequence).
  //  (c) Use `kFailedPrecondition` if the client should not retry until
  //      the system state has been explicitly fixed. For example, if a "rmdir"
  //      fails because the directory is non-empty, `kFailedPrecondition`
  //      should be returned since the client should not retry unless
  //      the files are deleted from the directory.
  kFailedPrecondition = 9,

  // AbslStatusCode::kAborted
  //
  // kAborted (gRPC code "ABORTED") indicates the operation was aborted,
  // typically due to a concurrency issue such as a sequencer check failure or a
  // failed transaction.
  //
  // See the guidelines above for deciding between `kFailedPrecondition`,
  // `kAborted`, and `kUnavailable`.
  kAborted = 10,

  // AbslStatusCode::kOutOfRange
  //
  // kOutOfRange (gRPC code "OUT_OF_RANGE") indicates the operation was
  // attempted past the valid range, such as seeking or reading past an
  // end-of-file.
  //
  // Unlike `kInvalidArgument`, this error indicates a problem that may
  // be fixed if the system state changes. For example, a 32-bit file
  // system will generate `kInvalidArgument` if asked to read at an
  // offset that is not in the range [0,2^32-1], but it will generate
  // `kOutOfRange` if asked to read from an offset past the current
  // file size.
  //
  // There is a fair bit of overlap between `kFailedPrecondition` and
  // `kOutOfRange`.  We recommend using `kOutOfRange` (the more specific
  // error) when it applies so that callers who are iterating through
  // a space can easily look for an `kOutOfRange` error to detect when
  // they are done.
  kOutOfRange = 11,

  // AbslStatusCode::kUnimplemented
  //
  // kUnimplemented (gRPC code "UNIMPLEMENTED") indicates the operation is not
  // implemented or supported in this service. In this case, the operation
  // should not be re-attempted.
  kUnimplemented = 12,

  // AbslStatusCode::kInternal
  //
  // kInternal (gRPC code "INTERNAL") indicates an internal error has occurred
  // and some invariants expected by the underlying system have not been
  // satisfied. This error code is reserved for serious errors.
  kInternal = 13,

  // AbslStatusCode::kUnavailable
  //
  // kUnavailable (gRPC code "UNAVAILABLE") indicates the service is currently
  // unavailable and that this is most likely a transient condition. An error
  // such as this can be corrected by retrying with a backoff scheme. Note that
  // it is not always safe to retry non-idempotent operations.
  //
  // See the guidelines above for deciding between `kFailedPrecondition`,
  // `kAborted`, and `kUnavailable`.
  kUnavailable = 14,

  // AbslStatusCode::kDataLoss
  //
  // kDataLoss (gRPC code "DATA_LOSS") indicates that unrecoverable data loss or
  // corruption has occurred. As this error is serious, proper alerting should
  // be attached to errors such as this.
  kDataLoss = 15,

  // AbslStatusCode::kUnauthenticated
  //
  // kUnauthenticated (gRPC code "UNAUTHENTICATED") indicates that the request
  // does not have valid authentication credentials for the operation. Correct
  // the authentication and try again.
  kUnauthenticated = 16,
};