go.uber.org/yarpc@v1.72.1/transport/http/constants.go

// Copyright (c) 2022 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package http

import "time"

// TransportName is the name of the transport.
//
// This value is what is used as transport.Request#Transport and transport.Namer
// for Outbounds.
const TransportName = "http"

var (
	defaultConnTimeout     = 500 * time.Millisecond
	defaultInnocenceWindow = 5 * time.Second
	defaultIdleConnTimeout = 15 * time.Minute
)

// HTTP headers used in requests and responses to send YARPC metadata.
const (
	// Name of the service sending the request. This corresponds to the
	// Request.Caller attribute.
	CallerHeader = "Rpc-Caller"

	// Name of the procedure of the caller sending the request. This corresponds to the
	// Request.CallerProcedure attribute.
	CallerProcedureHeader = "Rpc-Caller-Procedure"

	// Name of the encoding used for the request body. This corresponds to the
	// Request.Encoding attribute.
	EncodingHeader = "Rpc-Encoding"

	// Amount of time (in milliseconds) within which the request is expected
	// to finish.
	TTLMSHeader = "Context-TTL-MS"

	// Name of the procedure being called. This corresponds to the
	// Request.Procedure attribute.
	ProcedureHeader = "Rpc-Procedure"

	// Name of the service to which the request is being sent. This
	// corresponds to the Request.Service attribute. This header is also used
	// in responses to ensure requests are processed by the correct service.
	ServiceHeader = "Rpc-Service"

	// Shard key used by the destined service to shard the request. This
	// corresponds to the Request.ShardKey attribute.
	ShardKeyHeader = "Rpc-Shard-Key"

	// The traffic group responsible for handling the request. This
	// corresponds to the Request.RoutingKey attribute.
	RoutingKeyHeader = "Rpc-Routing-Key"

	// A service that can proxy the destined service. This corresponds to the
	// Request.RoutingDelegate attribute.
	RoutingDelegateHeader = "Rpc-Routing-Delegate"

	// Whether the response body contains an application error.
	ApplicationStatusHeader = "Rpc-Status"

	// ErrorCodeHeader contains the string representation of the error code.
	ErrorCodeHeader = "Rpc-Error-Code"

	// ErrorNameHeader contains the name of a user-defined error.
	ErrorNameHeader = "Rpc-Error-Name"

	// ErrorMessageHeader contains the message of an error, if the
	// BothResponseError feature is enabled.
	ErrorMessageHeader = "Rpc-Error-Message"

	// ErrorDetailsHeader contains the marshaled bytes of an error. Because
	// error details are mainly a gRPC concept, we use the header key name that
	// gRPC uses.
	// https://github.com/grpc/grpc-go/blob/04ea82009cdb9ecdefc6289f4c93ec919a10b3b6/internal/transport/handler_server.go#L218
	ErrorDetailsHeader = "Grpc-Status-Details-Bin"

	// AcceptsBothResponseErrorHeader says that the BothResponseError
	// feature is supported on the client. If the value is "true",
	// this indicates true.
	AcceptsBothResponseErrorHeader = "Rpc-Accepts-Both-Response-Error"

	// BothResponseErrorHeader says that the BothResponseError
	// feature is supported on the server. If any non-empty value is set,
	// this indicates true.
	BothResponseErrorHeader = "Rpc-Both-Response-Error"
)

const (
	// Headers for propagating transport.ApplicationErrorMeta.
	_applicationErrorNameHeader    = "Rpc-Application-Error-Name"
	_applicationErrorCodeHeader    = "Rpc-Application-Error-Code"
	_applicationErrorDetailsHeader = "Rpc-Application-Error-Details"

	// largest header value length for `transport.ApplicationErrorMeta#Details`
	_maxAppErrDetailsHeaderLen = 256
	// truncated message if we've exceeded the '_maxAppErrDetailsHeaderLen'
	_truncatedHeaderMessage = " (truncated)"
)

// Valid values for the Rpc-Status header.
const (
	// The request was successful.
	ApplicationSuccessStatus = "success"

	// An error occurred. The response body contains an application header.
	ApplicationErrorStatus = "error"

	// AcceptTrue is the true value used for accept headers.
	AcceptTrue = "true"
)

// ApplicationHeaderPrefix is the prefix added to application header keys to
// send them in requests or responses.
const ApplicationHeaderPrefix = "Rpc-Header-"

const (
	_http2AuthorityPseudoHeader = ":authority"
	_http2MethodPseudoHeader    = ":method"
	_http2PathPseudoHeader      = ":path"
	_http2SchemePseudoHeader    = ":scheme"
)

var (
	// list of pseusdo htt2 headers from https://tools.ietf.org/html/rfc7540#section-8.1.2.3
	_http2PseudoHeaders = []string{
		_http2AuthorityPseudoHeader,
		_http2MethodPseudoHeader,
		_http2PathPseudoHeader,
		_http2SchemePseudoHeader,
	}
)