diff options
Diffstat (limited to 'vendor/github.com/prometheus/common/expfmt/expfmt.go')
-rw-r--r-- | vendor/github.com/prometheus/common/expfmt/expfmt.go | 144 |
1 files changed, 134 insertions, 10 deletions
diff --git a/vendor/github.com/prometheus/common/expfmt/expfmt.go b/vendor/github.com/prometheus/common/expfmt/expfmt.go index c4cb20f0d..6fc9555e3 100644 --- a/vendor/github.com/prometheus/common/expfmt/expfmt.go +++ b/vendor/github.com/prometheus/common/expfmt/expfmt.go @@ -14,30 +14,154 @@ // Package expfmt contains tools for reading and writing Prometheus metrics. package expfmt +import ( + "strings" + + "github.com/prometheus/common/model" +) + // Format specifies the HTTP content type of the different wire protocols. type Format string -// Constants to assemble the Content-Type values for the different wire protocols. +// Constants to assemble the Content-Type values for the different wire +// protocols. The Content-Type strings here are all for the legacy exposition +// formats, where valid characters for metric names and label names are limited. +// Support for arbitrary UTF-8 characters in those names is already partially +// implemented in this module (see model.ValidationScheme), but to actually use +// it on the wire, new content-type strings will have to be agreed upon and +// added here. const ( TextVersion = "0.0.4" ProtoType = `application/vnd.google.protobuf` ProtoProtocol = `io.prometheus.client.MetricFamily` - ProtoFmt = ProtoType + "; proto=" + ProtoProtocol + ";" + protoFmt = ProtoType + "; proto=" + ProtoProtocol + ";" OpenMetricsType = `application/openmetrics-text` OpenMetricsVersion_0_0_1 = "0.0.1" OpenMetricsVersion_1_0_0 = "1.0.0" - // The Content-Type values for the different wire protocols. - FmtUnknown Format = `<unknown>` - FmtText Format = `text/plain; version=` + TextVersion + `; charset=utf-8` - FmtProtoDelim Format = ProtoFmt + ` encoding=delimited` - FmtProtoText Format = ProtoFmt + ` encoding=text` - FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text` - FmtOpenMetrics_1_0_0 Format = OpenMetricsType + `; version=` + OpenMetricsVersion_1_0_0 + `; charset=utf-8` - FmtOpenMetrics_0_0_1 Format = OpenMetricsType + `; version=` + OpenMetricsVersion_0_0_1 + `; charset=utf-8` + // The Content-Type values for the different wire protocols. Note that these + // values are now unexported. If code was relying on comparisons to these + // constants, instead use FormatType(). + fmtUnknown Format = `<unknown>` + fmtText Format = `text/plain; version=` + TextVersion + `; charset=utf-8` + fmtProtoDelim Format = protoFmt + ` encoding=delimited` + fmtProtoText Format = protoFmt + ` encoding=text` + fmtProtoCompact Format = protoFmt + ` encoding=compact-text` + fmtOpenMetrics_1_0_0 Format = OpenMetricsType + `; version=` + OpenMetricsVersion_1_0_0 + `; charset=utf-8` + fmtOpenMetrics_0_0_1 Format = OpenMetricsType + `; version=` + OpenMetricsVersion_0_0_1 + `; charset=utf-8` ) const ( hdrContentType = "Content-Type" hdrAccept = "Accept" ) + +// FormatType is a Go enum representing the overall category for the given +// Format. As the number of Format permutations increases, doing basic string +// comparisons are not feasible, so this enum captures the most useful +// high-level attribute of the Format string. +type FormatType int + +const ( + TypeUnknown = iota + TypeProtoCompact + TypeProtoDelim + TypeProtoText + TypeTextPlain + TypeOpenMetrics +) + +// NewFormat generates a new Format from the type provided. Mostly used for +// tests, most Formats should be generated as part of content negotiation in +// encode.go. +func NewFormat(t FormatType) Format { + switch t { + case TypeProtoCompact: + return fmtProtoCompact + case TypeProtoDelim: + return fmtProtoDelim + case TypeProtoText: + return fmtProtoText + case TypeTextPlain: + return fmtText + case TypeOpenMetrics: + return fmtOpenMetrics_1_0_0 + default: + return fmtUnknown + } +} + +// FormatType deduces an overall FormatType for the given format. +func (f Format) FormatType() FormatType { + toks := strings.Split(string(f), ";") + if len(toks) < 2 { + return TypeUnknown + } + + params := make(map[string]string) + for i, t := range toks { + if i == 0 { + continue + } + args := strings.Split(t, "=") + if len(args) != 2 { + continue + } + params[strings.TrimSpace(args[0])] = strings.TrimSpace(args[1]) + } + + switch strings.TrimSpace(toks[0]) { + case ProtoType: + if params["proto"] != ProtoProtocol { + return TypeUnknown + } + switch params["encoding"] { + case "delimited": + return TypeProtoDelim + case "text": + return TypeProtoText + case "compact-text": + return TypeProtoCompact + default: + return TypeUnknown + } + case OpenMetricsType: + if params["charset"] != "utf-8" { + return TypeUnknown + } + return TypeOpenMetrics + case "text/plain": + v, ok := params["version"] + if !ok { + return TypeTextPlain + } + if v == TextVersion { + return TypeTextPlain + } + return TypeUnknown + default: + return TypeUnknown + } +} + +// ToEscapingScheme returns an EscapingScheme depending on the Format. Iff the +// Format contains a escaping=allow-utf-8 term, it will select NoEscaping. If a valid +// "escaping" term exists, that will be used. Otherwise, the global default will +// be returned. +func (format Format) ToEscapingScheme() model.EscapingScheme { + for _, p := range strings.Split(string(format), ";") { + toks := strings.Split(p, "=") + if len(toks) != 2 { + continue + } + key, value := strings.TrimSpace(toks[0]), strings.TrimSpace(toks[1]) + if key == model.EscapingKey { + scheme, err := model.ToEscapingScheme(value) + if err != nil { + return model.NameEscapingScheme + } + return scheme + } + } + return model.NameEscapingScheme +} |