[VOL-4291] Rw-core updates for gRPC migration
Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/prometheus/common/expfmt/encode.go b/vendor/github.com/prometheus/common/expfmt/encode.go
index 11839ed..bd4e347 100644
--- a/vendor/github.com/prometheus/common/expfmt/encode.go
+++ b/vendor/github.com/prometheus/common/expfmt/encode.go
@@ -30,17 +30,38 @@
Encode(*dto.MetricFamily) error
}
-type encoder func(*dto.MetricFamily) error
-
-func (e encoder) Encode(v *dto.MetricFamily) error {
- return e(v)
+// Closer is implemented by Encoders that need to be closed to finalize
+// encoding. (For example, OpenMetrics needs a final `# EOF` line.)
+//
+// Note that all Encoder implementations returned from this package implement
+// Closer, too, even if the Close call is a no-op. This happens in preparation
+// for adding a Close method to the Encoder interface directly in a (mildly
+// breaking) release in the future.
+type Closer interface {
+ Close() error
}
-// Negotiate returns the Content-Type based on the given Accept header.
-// If no appropriate accepted type is found, FmtText is returned.
+type encoderCloser struct {
+ encode func(*dto.MetricFamily) error
+ close func() error
+}
+
+func (ec encoderCloser) Encode(v *dto.MetricFamily) error {
+ return ec.encode(v)
+}
+
+func (ec encoderCloser) Close() error {
+ return ec.close()
+}
+
+// Negotiate returns the Content-Type based on the given Accept header. If no
+// appropriate accepted type is found, FmtText is returned (which is the
+// Prometheus text format). This function will never negotiate FmtOpenMetrics,
+// as the support is still experimental. To include the option to negotiate
+// FmtOpenMetrics, use NegotiateOpenMetrics.
func Negotiate(h http.Header) Format {
for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
- // Check for protocol buffer
+ ver := ac.Params["version"]
if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
switch ac.Params["encoding"] {
case "delimited":
@@ -51,8 +72,6 @@
return FmtProtoCompact
}
}
- // Check for text format.
- ver := ac.Params["version"]
if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
return FmtText
}
@@ -60,29 +79,84 @@
return FmtText
}
-// NewEncoder returns a new encoder based on content type negotiation.
+// NegotiateIncludingOpenMetrics works like Negotiate but includes
+// FmtOpenMetrics as an option for the result. Note that this function is
+// temporary and will disappear once FmtOpenMetrics is fully supported and as
+// such may be negotiated by the normal Negotiate function.
+func NegotiateIncludingOpenMetrics(h http.Header) Format {
+ for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
+ ver := ac.Params["version"]
+ if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
+ switch ac.Params["encoding"] {
+ case "delimited":
+ return FmtProtoDelim
+ case "text":
+ return FmtProtoText
+ case "compact-text":
+ return FmtProtoCompact
+ }
+ }
+ if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
+ return FmtText
+ }
+ if ac.Type+"/"+ac.SubType == OpenMetricsType && (ver == OpenMetricsVersion || ver == "") {
+ return FmtOpenMetrics
+ }
+ }
+ return FmtText
+}
+
+// NewEncoder returns a new encoder based on content type negotiation. All
+// Encoder implementations returned by NewEncoder also implement Closer, and
+// callers should always call the Close method. It is currently only required
+// for FmtOpenMetrics, but a future (breaking) release will add the Close method
+// to the Encoder interface directly. The current version of the Encoder
+// interface is kept for backwards compatibility.
func NewEncoder(w io.Writer, format Format) Encoder {
switch format {
case FmtProtoDelim:
- return encoder(func(v *dto.MetricFamily) error {
- _, err := pbutil.WriteDelimited(w, v)
- return err
- })
+ return encoderCloser{
+ encode: func(v *dto.MetricFamily) error {
+ _, err := pbutil.WriteDelimited(w, v)
+ return err
+ },
+ close: func() error { return nil },
+ }
case FmtProtoCompact:
- return encoder(func(v *dto.MetricFamily) error {
- _, err := fmt.Fprintln(w, v.String())
- return err
- })
+ return encoderCloser{
+ encode: func(v *dto.MetricFamily) error {
+ _, err := fmt.Fprintln(w, v.String())
+ return err
+ },
+ close: func() error { return nil },
+ }
case FmtProtoText:
- return encoder(func(v *dto.MetricFamily) error {
- _, err := fmt.Fprintln(w, proto.MarshalTextString(v))
- return err
- })
+ return encoderCloser{
+ encode: func(v *dto.MetricFamily) error {
+ _, err := fmt.Fprintln(w, proto.MarshalTextString(v))
+ return err
+ },
+ close: func() error { return nil },
+ }
case FmtText:
- return encoder(func(v *dto.MetricFamily) error {
- _, err := MetricFamilyToText(w, v)
- return err
- })
+ return encoderCloser{
+ encode: func(v *dto.MetricFamily) error {
+ _, err := MetricFamilyToText(w, v)
+ return err
+ },
+ close: func() error { return nil },
+ }
+ case FmtOpenMetrics:
+ return encoderCloser{
+ encode: func(v *dto.MetricFamily) error {
+ _, err := MetricFamilyToOpenMetrics(w, v)
+ return err
+ },
+ close: func() error {
+ _, err := FinalizeOpenMetrics(w)
+ return err
+ },
+ }
}
- panic("expfmt.NewEncoder: unknown format")
+ panic(fmt.Errorf("expfmt.NewEncoder: unknown format %q", format))
}