Module types 

A collection of useful protobuf types that can be used with rama-grpc.

This crate also introduces the StatusExt trait and implements it in crate::Status, allowing the implementation of the gRPC Richer Error Model with rama-grpc in a convenient way.

Usage

Useful protobuf types are available through the pb module. They can be imported and worked with directly.

The StatusExt trait adds associated functions to crate::Status that can be used on the server side to create a status with error details, which can then be returned to gRPC clients. Moreover, the trait also adds methods to crate::Status that can be used by a rama-grpc client to extract error details, and handle them with ease.

Working with different error message types

Multiple examples are provided at the ErrorDetails doc. Instructions about how to use the fields of the standard error message types correctly are provided at error_details.proto.

Alternative crate::Status associated functions and methods

In the StatusExt doc, an alternative way of interacting with crate::Status is presented, using vectors of error details structs wrapped with the ErrorDetail enum. This approach can provide more control over the vector of standard error messages that will be generated or that was received, if necessary. To see how to adopt this approach, please check the StatusExt::try_with_error_details_vec and StatusExt::get_error_details_vec docs.

Besides that, multiple examples with alternative error details extraction methods are provided in the StatusExt doc, which can be specially useful if only one type of standard error message is being handled by the client. For example, using StatusExt::get_details_bad_request is a more direct way of extracting a BadRequest error message from crate::Status.

Modules

pb

Useful protobuf types

Structs

BadRequest

Used to encode/decode the BadRequest standard error message described in error_details.proto. Describes violations in a client request. Focuses on the syntactic aspects of the request.

DebugInfo

Used to encode/decode the DebugInfo standard error message described in error_details.proto. Describes additional debugging info.

ErrorDetails

Groups the standard error messages structs. Provides associated functions and methods to setup and edit each error message independently. Used when extracting error details from crate::Status, and when creating a crate::Status with error details.

ErrorInfo

Used to encode/decode the ErrorInfo standard error message described in error_details.proto. Describes the cause of the error with structured details.

FieldViolation

Used at the field_violations field of the BadRequest struct. Describes a single bad request field.

Help

Used to encode/decode the Help standard error message described in error_details.proto. Provides links to documentation or for performing an out-of-band action.

HelpLink

Used at the links field of the Help struct. Describes a URL link.

LocalizedMessage

Used to encode/decode the LocalizedMessage standard error message described in error_details.proto. Provides a localized error message that is safe to return to the user.

PreconditionFailure

Used to encode/decode the PreconditionFailure standard error message described in error_details.proto. Describes what preconditions have failed.

PreconditionViolation

Used at the violations field of the PreconditionFailure struct. Describes a single precondition failure.

QuotaFailure

Used to encode/decode the QuotaFailure standard error message described in error_details.proto. Describes how a quota check failed.

QuotaViolation

Used at the violations field of the QuotaFailure struct. Describes a single quota violation.

RequestInfo

Used to encode/decode the RequestInfo standard error message described in error_details.proto. Contains metadata about the request that clients can attach when providing feedback.

ResourceInfo

Used to encode/decode the ResourceInfo standard error message described in error_details.proto. Describes the resource that is being accessed.

RetryInfo

Used to encode/decode the RetryInfo standard error message described in error_details.proto. Describes when the clients can retry a failed request. Note: When obtained from decoding RetryInfo messages, negative retry_delay’s become 0.

Status

The Status type defines a logical error model that is suitable for different programming environments, including REST APIs and RPC APIs. It is used by gRPC. Each Status message contains three pieces of data: error code, error message, and error details.

Enums

ErrorDetail

Wraps the structs corresponding to the standard error messages, allowing the implementation and handling of vectors containing any of them.

Traits

RpcStatusExt

Used to implement associated functions and methods on pb::Status, that allow the extraction of standard error details. This trait is sealed and not meant to be implemented outside of rama::grpc::protobuf::types.

StatusExt

Used to implement associated functions and methods on Status, that allow the addition and extraction of standard error details. This trait is sealed and not meant to be implemented outside of rama::grpc::protobuf::types.