[feature] Initial Prometheus metrics implementation (#2334)

* feat: Initial OTEL metrics

* docs: add metrics documentation

* fix: metrics endpoint conditional check

* feat: metrics endpoint basic auth

* fix: make metrics-auth-enabled default false

* fix: go fmt helpers.gen.go

* fix: add metric-related env vars to envparsing.sh

* fix: metrics docs

* fix: metrics related stuff in envparsing.sh

* fix: metrics docs

* chore: metrics docs wording

* fix: metrics stuff in envparsing?

* bump otel versions

---------

Co-authored-by: Tsuribori <user@acertaindebian>
Co-authored-by: Tsuribori <none@example.org>
Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>

1 files changed, 381 insertions, 0 deletions

diff --git a/vendor/github.com/prometheus/procfs/proc_snmp6.go b/vendor/github.com/prometheus/procfs/proc_snmp6.go
new file mode 100644
index 000000000..3059cc6a1
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_snmp6.go
@@ -0,0 +1,381 @@
+// Copyright 2022 The Prometheus Authors
+// 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 procfs
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ProcSnmp6 models the content of /proc/<pid>/net/snmp6.
+type ProcSnmp6 struct {
+	// The process ID.
+	PID int
+	Ip6
+	Icmp6
+	Udp6
+	UdpLite6
+}
+
+type Ip6 struct { // nolint:revive
+	InReceives       *float64
+	InHdrErrors      *float64
+	InTooBigErrors   *float64
+	InNoRoutes       *float64
+	InAddrErrors     *float64
+	InUnknownProtos  *float64
+	InTruncatedPkts  *float64
+	InDiscards       *float64
+	InDelivers       *float64
+	OutForwDatagrams *float64
+	OutRequests      *float64
+	OutDiscards      *float64
+	OutNoRoutes      *float64
+	ReasmTimeout     *float64
+	ReasmReqds       *float64
+	ReasmOKs         *float64
+	ReasmFails       *float64
+	FragOKs          *float64
+	FragFails        *float64
+	FragCreates      *float64
+	InMcastPkts      *float64
+	OutMcastPkts     *float64
+	InOctets         *float64
+	OutOctets        *float64
+	InMcastOctets    *float64
+	OutMcastOctets   *float64
+	InBcastOctets    *float64
+	OutBcastOctets   *float64
+	InNoECTPkts      *float64
+	InECT1Pkts       *float64
+	InECT0Pkts       *float64
+	InCEPkts         *float64
+}
+
+type Icmp6 struct {
+	InMsgs                    *float64
+	InErrors                  *float64
+	OutMsgs                   *float64
+	OutErrors                 *float64
+	InCsumErrors              *float64
+	InDestUnreachs            *float64
+	InPktTooBigs              *float64
+	InTimeExcds               *float64
+	InParmProblems            *float64
+	InEchos                   *float64
+	InEchoReplies             *float64
+	InGroupMembQueries        *float64
+	InGroupMembResponses      *float64
+	InGroupMembReductions     *float64
+	InRouterSolicits          *float64
+	InRouterAdvertisements    *float64
+	InNeighborSolicits        *float64
+	InNeighborAdvertisements  *float64
+	InRedirects               *float64
+	InMLDv2Reports            *float64
+	OutDestUnreachs           *float64
+	OutPktTooBigs             *float64
+	OutTimeExcds              *float64
+	OutParmProblems           *float64
+	OutEchos                  *float64
+	OutEchoReplies            *float64
+	OutGroupMembQueries       *float64
+	OutGroupMembResponses     *float64
+	OutGroupMembReductions    *float64
+	OutRouterSolicits         *float64
+	OutRouterAdvertisements   *float64
+	OutNeighborSolicits       *float64
+	OutNeighborAdvertisements *float64
+	OutRedirects              *float64
+	OutMLDv2Reports           *float64
+	InType1                   *float64
+	InType134                 *float64
+	InType135                 *float64
+	InType136                 *float64
+	InType143                 *float64
+	OutType133                *float64
+	OutType135                *float64
+	OutType136                *float64
+	OutType143                *float64
+}
+
+type Udp6 struct { // nolint:revive
+	InDatagrams  *float64
+	NoPorts      *float64
+	InErrors     *float64
+	OutDatagrams *float64
+	RcvbufErrors *float64
+	SndbufErrors *float64
+	InCsumErrors *float64
+	IgnoredMulti *float64
+}
+
+type UdpLite6 struct { // nolint:revive
+	InDatagrams  *float64
+	NoPorts      *float64
+	InErrors     *float64
+	OutDatagrams *float64
+	RcvbufErrors *float64
+	SndbufErrors *float64
+	InCsumErrors *float64
+}
+
+func (p Proc) Snmp6() (ProcSnmp6, error) {
+	filename := p.path("net/snmp6")
+	data, err := util.ReadFileNoStat(filename)
+	if err != nil {
+		// On systems with IPv6 disabled, this file won't exist.
+		// Do nothing.
+		if errors.Is(err, os.ErrNotExist) {
+			return ProcSnmp6{PID: p.PID}, nil
+		}
+
+		return ProcSnmp6{PID: p.PID}, err
+	}
+
+	procSnmp6, err := parseSNMP6Stats(bytes.NewReader(data))
+	procSnmp6.PID = p.PID
+	return procSnmp6, err
+}
+
+// parseSnmp6 parses the metrics from proc/<pid>/net/snmp6 file
+// and returns a map contains those metrics.
+func parseSNMP6Stats(r io.Reader) (ProcSnmp6, error) {
+	var (
+		scanner   = bufio.NewScanner(r)
+		procSnmp6 = ProcSnmp6{}
+	)
+
+	for scanner.Scan() {
+		stat := strings.Fields(scanner.Text())
+		if len(stat) < 2 {
+			continue
+		}
+		// Expect to have "6" in metric name, skip line otherwise
+		if sixIndex := strings.Index(stat[0], "6"); sixIndex != -1 {
+			protocol := stat[0][:sixIndex+1]
+			key := stat[0][sixIndex+1:]
+			value, err := strconv.ParseFloat(stat[1], 64)
+			if err != nil {
+				return procSnmp6, err
+			}
+
+			switch protocol {
+			case "Ip6":
+				switch key {
+				case "InReceives":
+					procSnmp6.Ip6.InReceives = &value
+				case "InHdrErrors":
+					procSnmp6.Ip6.InHdrErrors = &value
+				case "InTooBigErrors":
+					procSnmp6.Ip6.InTooBigErrors = &value
+				case "InNoRoutes":
+					procSnmp6.Ip6.InNoRoutes = &value
+				case "InAddrErrors":
+					procSnmp6.Ip6.InAddrErrors = &value
+				case "InUnknownProtos":
+					procSnmp6.Ip6.InUnknownProtos = &value
+				case "InTruncatedPkts":
+					procSnmp6.Ip6.InTruncatedPkts = &value
+				case "InDiscards":
+					procSnmp6.Ip6.InDiscards = &value
+				case "InDelivers":
+					procSnmp6.Ip6.InDelivers = &value
+				case "OutForwDatagrams":
+					procSnmp6.Ip6.OutForwDatagrams = &value
+				case "OutRequests":
+					procSnmp6.Ip6.OutRequests = &value
+				case "OutDiscards":
+					procSnmp6.Ip6.OutDiscards = &value
+				case "OutNoRoutes":
+					procSnmp6.Ip6.OutNoRoutes = &value
+				case "ReasmTimeout":
+					procSnmp6.Ip6.ReasmTimeout = &value
+				case "ReasmReqds":
+					procSnmp6.Ip6.ReasmReqds = &value
+				case "ReasmOKs":
+					procSnmp6.Ip6.ReasmOKs = &value
+				case "ReasmFails":
+					procSnmp6.Ip6.ReasmFails = &value
+				case "FragOKs":
+					procSnmp6.Ip6.FragOKs = &value
+				case "FragFails":
+					procSnmp6.Ip6.FragFails = &value
+				case "FragCreates":
+					procSnmp6.Ip6.FragCreates = &value
+				case "InMcastPkts":
+					procSnmp6.Ip6.InMcastPkts = &value
+				case "OutMcastPkts":
+					procSnmp6.Ip6.OutMcastPkts = &value
+				case "InOctets":
+					procSnmp6.Ip6.InOctets = &value
+				case "OutOctets":
+					procSnmp6.Ip6.OutOctets = &value
+				case "InMcastOctets":
+					procSnmp6.Ip6.InMcastOctets = &value
+				case "OutMcastOctets":
+					procSnmp6.Ip6.OutMcastOctets = &value
+				case "InBcastOctets":
+					procSnmp6.Ip6.InBcastOctets = &value
+				case "OutBcastOctets":
+					procSnmp6.Ip6.OutBcastOctets = &value
+				case "InNoECTPkts":
+					procSnmp6.Ip6.InNoECTPkts = &value
+				case "InECT1Pkts":
+					procSnmp6.Ip6.InECT1Pkts = &value
+				case "InECT0Pkts":
+					procSnmp6.Ip6.InECT0Pkts = &value
+				case "InCEPkts":
+					procSnmp6.Ip6.InCEPkts = &value
+
+				}
+			case "Icmp6":
+				switch key {
+				case "InMsgs":
+					procSnmp6.Icmp6.InMsgs = &value
+				case "InErrors":
+					procSnmp6.Icmp6.InErrors = &value
+				case "OutMsgs":
+					procSnmp6.Icmp6.OutMsgs = &value
+				case "OutErrors":
+					procSnmp6.Icmp6.OutErrors = &value
+				case "InCsumErrors":
+					procSnmp6.Icmp6.InCsumErrors = &value
+				case "InDestUnreachs":
+					procSnmp6.Icmp6.InDestUnreachs = &value
+				case "InPktTooBigs":
+					procSnmp6.Icmp6.InPktTooBigs = &value
+				case "InTimeExcds":
+					procSnmp6.Icmp6.InTimeExcds = &value
+				case "InParmProblems":
+					procSnmp6.Icmp6.InParmProblems = &value
+				case "InEchos":
+					procSnmp6.Icmp6.InEchos = &value
+				case "InEchoReplies":
+					procSnmp6.Icmp6.InEchoReplies = &value
+				case "InGroupMembQueries":
+					procSnmp6.Icmp6.InGroupMembQueries = &value
+				case "InGroupMembResponses":
+					procSnmp6.Icmp6.InGroupMembResponses = &value
+				case "InGroupMembReductions":
+					procSnmp6.Icmp6.InGroupMembReductions = &value
+				case "InRouterSolicits":
+					procSnmp6.Icmp6.InRouterSolicits = &value
+				case "InRouterAdvertisements":
+					procSnmp6.Icmp6.InRouterAdvertisements = &value
+				case "InNeighborSolicits":
+					procSnmp6.Icmp6.InNeighborSolicits = &value
+				case "InNeighborAdvertisements":
+					procSnmp6.Icmp6.InNeighborAdvertisements = &value
+				case "InRedirects":
+					procSnmp6.Icmp6.InRedirects = &value
+				case "InMLDv2Reports":
+					procSnmp6.Icmp6.InMLDv2Reports = &value
+				case "OutDestUnreachs":
+					procSnmp6.Icmp6.OutDestUnreachs = &value
+				case "OutPktTooBigs":
+					procSnmp6.Icmp6.OutPktTooBigs = &value
+				case "OutTimeExcds":
+					procSnmp6.Icmp6.OutTimeExcds = &value
+				case "OutParmProblems":
+					procSnmp6.Icmp6.OutParmProblems = &value
+				case "OutEchos":
+					procSnmp6.Icmp6.OutEchos = &value
+				case "OutEchoReplies":
+					procSnmp6.Icmp6.OutEchoReplies = &value
+				case "OutGroupMembQueries":
+					procSnmp6.Icmp6.OutGroupMembQueries = &value
+				case "OutGroupMembResponses":
+					procSnmp6.Icmp6.OutGroupMembResponses = &value
+				case "OutGroupMembReductions":
+					procSnmp6.Icmp6.OutGroupMembReductions = &value
+				case "OutRouterSolicits":
+					procSnmp6.Icmp6.OutRouterSolicits = &value
+				case "OutRouterAdvertisements":
+					procSnmp6.Icmp6.OutRouterAdvertisements = &value
+				case "OutNeighborSolicits":
+					procSnmp6.Icmp6.OutNeighborSolicits = &value
+				case "OutNeighborAdvertisements":
+					procSnmp6.Icmp6.OutNeighborAdvertisements = &value
+				case "OutRedirects":
+					procSnmp6.Icmp6.OutRedirects = &value
+				case "OutMLDv2Reports":
+					procSnmp6.Icmp6.OutMLDv2Reports = &value
+				case "InType1":
+					procSnmp6.Icmp6.InType1 = &value
+				case "InType134":
+					procSnmp6.Icmp6.InType134 = &value
+				case "InType135":
+					procSnmp6.Icmp6.InType135 = &value
+				case "InType136":
+					procSnmp6.Icmp6.InType136 = &value
+				case "InType143":
+					procSnmp6.Icmp6.InType143 = &value
+				case "OutType133":
+					procSnmp6.Icmp6.OutType133 = &value
+				case "OutType135":
+					procSnmp6.Icmp6.OutType135 = &value
+				case "OutType136":
+					procSnmp6.Icmp6.OutType136 = &value
+				case "OutType143":
+					procSnmp6.Icmp6.OutType143 = &value
+				}
+			case "Udp6":
+				switch key {
+				case "InDatagrams":
+					procSnmp6.Udp6.InDatagrams = &value
+				case "NoPorts":
+					procSnmp6.Udp6.NoPorts = &value
+				case "InErrors":
+					procSnmp6.Udp6.InErrors = &value
+				case "OutDatagrams":
+					procSnmp6.Udp6.OutDatagrams = &value
+				case "RcvbufErrors":
+					procSnmp6.Udp6.RcvbufErrors = &value
+				case "SndbufErrors":
+					procSnmp6.Udp6.SndbufErrors = &value
+				case "InCsumErrors":
+					procSnmp6.Udp6.InCsumErrors = &value
+				case "IgnoredMulti":
+					procSnmp6.Udp6.IgnoredMulti = &value
+				}
+			case "UdpLite6":
+				switch key {
+				case "InDatagrams":
+					procSnmp6.UdpLite6.InDatagrams = &value
+				case "NoPorts":
+					procSnmp6.UdpLite6.NoPorts = &value
+				case "InErrors":
+					procSnmp6.UdpLite6.InErrors = &value
+				case "OutDatagrams":
+					procSnmp6.UdpLite6.OutDatagrams = &value
+				case "RcvbufErrors":
+					procSnmp6.UdpLite6.RcvbufErrors = &value
+				case "SndbufErrors":
+					procSnmp6.UdpLite6.SndbufErrors = &value
+				case "InCsumErrors":
+					procSnmp6.UdpLite6.InCsumErrors = &value
+				}
+			}
+		}
+	}
+	return procSnmp6, scanner.Err()
+}