vendor/cloud.google.com/go/internal/trace/trace.go

   1 // Copyright 2018 Google LLC
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //      http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 package trace
  16
  17 import (
  18         "context"
  19
  20         "go.opencensus.io/trace"
  21         "google.golang.org/api/googleapi"
  22         "google.golang.org/genproto/googleapis/rpc/code"
  23         "google.golang.org/grpc/status"
  24 )
  25
  26 // StartSpan adds a span to the trace with the given name.
  27 func StartSpan(ctx context.Context, name string) context.Context {
  28         ctx, _ = trace.StartSpan(ctx, name)
  29         return ctx
  30 }
  31
  32 // EndSpan ends a span with the given error.
  33 func EndSpan(ctx context.Context, err error) {
  34         span := trace.FromContext(ctx)
  35         if err != nil {
  36                 span.SetStatus(toStatus(err))
  37         }
  38         span.End()
  39 }
  40
  41 // ToStatus interrogates an error and converts it to an appropriate
  42 // OpenCensus status.
  43 func toStatus(err error) trace.Status {
  44         if err2, ok := err.(*googleapi.Error); ok {
  45                 return trace.Status{Code: httpStatusCodeToOCCode(err2.Code), Message: err2.Message}
  46         } else if s, ok := status.FromError(err); ok {
  47                 return trace.Status{Code: int32(s.Code()), Message: s.Message()}
  48         } else {
  49                 return trace.Status{Code: int32(code.Code_UNKNOWN), Message: err.Error()}
  50         }
  51 }
  52
  53 // TODO (deklerk): switch to using OpenCensus function when it becomes available.
  54 // Reference: https://github.com/googleapis/googleapis/blob/26b634d2724ac5dd30ae0b0cbfb01f07f2e4050e/google/rpc/code.proto
  55 func httpStatusCodeToOCCode(httpStatusCode int) int32 {
  56         switch httpStatusCode {
  57         case 200:
  58                 return int32(code.Code_OK)
  59         case 499:
  60                 return int32(code.Code_CANCELLED)
  61         case 500:
  62                 return int32(code.Code_UNKNOWN) // Could also be Code_INTERNAL, Code_DATA_LOSS
  63         case 400:
  64                 return int32(code.Code_INVALID_ARGUMENT) // Could also be Code_OUT_OF_RANGE
  65         case 504:
  66                 return int32(code.Code_DEADLINE_EXCEEDED)
  67         case 404:
  68                 return int32(code.Code_NOT_FOUND)
  69         case 409:
  70                 return int32(code.Code_ALREADY_EXISTS) // Could also be Code_ABORTED
  71         case 403:
  72                 return int32(code.Code_PERMISSION_DENIED)
  73         case 401:
  74                 return int32(code.Code_UNAUTHENTICATED)
  75         case 429:
  76                 return int32(code.Code_RESOURCE_EXHAUSTED)
  77         case 501:
  78                 return int32(code.Code_UNIMPLEMENTED)
  79         case 503:
  80                 return int32(code.Code_UNAVAILABLE)
  81         default:
  82                 return int32(code.Code_UNKNOWN)
  83         }
  84 }