mirror of https://github.com/prometheus/prometheus
62 lines
2.0 KiB
Go
62 lines
2.0 KiB
Go
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package runtime
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import (
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"io"
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"net/http"
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"golang.org/x/net/context"
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"google.golang.org/grpc/codes"
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"google.golang.org/grpc/grpclog"
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"google.golang.org/grpc/status"
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)
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// ProtoErrorHandlerFunc handles the error as a gRPC error generated via status package and replies to the request.
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type ProtoErrorHandlerFunc func(context.Context, *ServeMux, Marshaler, http.ResponseWriter, *http.Request, error)
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var _ ProtoErrorHandlerFunc = DefaultHTTPProtoErrorHandler
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// DefaultHTTPProtoErrorHandler is an implementation of HTTPError.
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// If "err" is an error from gRPC system, the function replies with the status code mapped by HTTPStatusFromCode.
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// If otherwise, it replies with http.StatusInternalServerError.
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//
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// The response body returned by this function is a Status message marshaled by a Marshaler.
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//
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// Do not set this function to HTTPError variable directly, use WithProtoErrorHandler option instead.
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func DefaultHTTPProtoErrorHandler(ctx context.Context, mux *ServeMux, marshaler Marshaler, w http.ResponseWriter, _ *http.Request, err error) {
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// return Internal when Marshal failed
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const fallback = `{"code": 13, "message": "failed to marshal error message"}`
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w.Header().Del("Trailer")
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w.Header().Set("Content-Type", marshaler.ContentType())
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s, ok := status.FromError(err)
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if !ok {
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s = status.New(codes.Unknown, err.Error())
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}
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buf, merr := marshaler.Marshal(s.Proto())
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if merr != nil {
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grpclog.Printf("Failed to marshal error message %q: %v", s.Proto(), merr)
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w.WriteHeader(http.StatusInternalServerError)
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if _, err := io.WriteString(w, fallback); err != nil {
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grpclog.Printf("Failed to write response: %v", err)
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}
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return
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}
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md, ok := ServerMetadataFromContext(ctx)
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if !ok {
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grpclog.Printf("Failed to extract ServerMetadata from context")
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}
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handleForwardResponseServerMetadata(w, mux, md)
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handleForwardResponseTrailerHeader(w, md)
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st := HTTPStatusFromCode(s.Code())
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w.WriteHeader(st)
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if _, err := w.Write(buf); err != nil {
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grpclog.Printf("Failed to write response: %v", err)
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}
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handleForwardResponseTrailer(w, md)
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}
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