grpc_http_mapper.go

// Copyright 2019 Splunk, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package translator

import (
	"net/http"
)

// This code is taken from OpenTelemetry project in order to avoid adding the whole project as a dependency.

// https://github.com/googleapis/googleapis/blob/bee79fbe03254a35db125dc6d2f1e9b752b390fe/google/rpc/code.proto#L33-L186
const (
	OCOK                 = 0
	OCCancelled          = 1
	OCUnknown            = 2
	OCInvalidArgument    = 3
	OCDeadlineExceeded   = 4
	OCNotFound           = 5
	OCAlreadyExists      = 6
	OCPermissionDenied   = 7
	OCResourceExhausted  = 8
	OCFailedPrecondition = 9
	OCAborted            = 10
	OCOutOfRange         = 11
	OCUnimplemented      = 12
	OCInternal           = 13
	OCUnavailable        = 14
	OCDataLoss           = 15
	OCUnauthenticated    = 16
)

var httpToOCCodeMap = map[int32]int32{
	401: OCUnauthenticated,
	403: OCPermissionDenied,
	404: OCNotFound,
	429: OCResourceExhausted,
	499: OCCancelled,
	501: OCUnimplemented,
	503: OCUnavailable,
	504: OCDeadlineExceeded,
}

// OCStatusCodeFromHTTP takes an HTTP status code and return the appropriate OpenTelemetry status code
// See: https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/data-http.md
func OCStatusCodeFromHTTP(code int32) int32 {
	if code >= 100 && code < 400 {
		return OCOK
	}
	if rvCode, ok := httpToOCCodeMap[code]; ok {
		return rvCode
	}
	if code >= 400 && code < 500 {
		return OCInvalidArgument
	}
	if code >= 500 && code < 600 {
		return OCInternal
	}
	return OCUnknown
}

var ocToHTTPCodeMap = map[int32]int32{
	OCOK:                 http.StatusOK,
	OCCancelled:          499,
	OCUnknown:            http.StatusInternalServerError,
	OCInvalidArgument:    http.StatusBadRequest,
	OCDeadlineExceeded:   http.StatusGatewayTimeout,
	OCNotFound:           http.StatusNotFound,
	OCAlreadyExists:      http.StatusConflict,
	OCPermissionDenied:   http.StatusForbidden,
	OCResourceExhausted:  http.StatusTooManyRequests,
	OCFailedPrecondition: http.StatusPreconditionFailed,
	OCAborted:            http.StatusConflict,
	OCOutOfRange:         http.StatusRequestedRangeNotSatisfiable,
	OCUnimplemented:      http.StatusNotImplemented,
	OCInternal:           http.StatusInternalServerError,
	OCUnavailable:        http.StatusServiceUnavailable,
	OCDataLoss:           http.StatusUnprocessableEntity,
	OCUnauthenticated:    http.StatusUnauthorized,
}

// HTTPStatusCodeFromOCStatus takes an OpenTelemetry status code and return the appropriate HTTP status code
// See: https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/data-http.md
func HTTPStatusCodeFromOCStatus(code int32) int32 {
	if rvCode, ok := ocToHTTPCodeMap[code]; ok {
		return rvCode
	}
	return http.StatusInternalServerError
}