[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, 443 insertions, 0 deletions

diff --git a/vendor/github.com/prometheus/procfs/proc_netstat.go b/vendor/github.com/prometheus/procfs/proc_netstat.go
new file mode 100644
index 000000000..8e3ff4d79
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/proc_netstat.go
@@ -0,0 +1,443 @@
+// 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"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ProcNetstat models the content of /proc/<pid>/net/netstat.
+type ProcNetstat struct {
+	// The process ID.
+	PID int
+	TcpExt
+	IpExt
+}
+
+type TcpExt struct { // nolint:revive
+	SyncookiesSent            *float64
+	SyncookiesRecv            *float64
+	SyncookiesFailed          *float64
+	EmbryonicRsts             *float64
+	PruneCalled               *float64
+	RcvPruned                 *float64
+	OfoPruned                 *float64
+	OutOfWindowIcmps          *float64
+	LockDroppedIcmps          *float64
+	ArpFilter                 *float64
+	TW                        *float64
+	TWRecycled                *float64
+	TWKilled                  *float64
+	PAWSActive                *float64
+	PAWSEstab                 *float64
+	DelayedACKs               *float64
+	DelayedACKLocked          *float64
+	DelayedACKLost            *float64
+	ListenOverflows           *float64
+	ListenDrops               *float64
+	TCPHPHits                 *float64
+	TCPPureAcks               *float64
+	TCPHPAcks                 *float64
+	TCPRenoRecovery           *float64
+	TCPSackRecovery           *float64
+	TCPSACKReneging           *float64
+	TCPSACKReorder            *float64
+	TCPRenoReorder            *float64
+	TCPTSReorder              *float64
+	TCPFullUndo               *float64
+	TCPPartialUndo            *float64
+	TCPDSACKUndo              *float64
+	TCPLossUndo               *float64
+	TCPLostRetransmit         *float64
+	TCPRenoFailures           *float64
+	TCPSackFailures           *float64
+	TCPLossFailures           *float64
+	TCPFastRetrans            *float64
+	TCPSlowStartRetrans       *float64
+	TCPTimeouts               *float64
+	TCPLossProbes             *float64
+	TCPLossProbeRecovery      *float64
+	TCPRenoRecoveryFail       *float64
+	TCPSackRecoveryFail       *float64
+	TCPRcvCollapsed           *float64
+	TCPDSACKOldSent           *float64
+	TCPDSACKOfoSent           *float64
+	TCPDSACKRecv              *float64
+	TCPDSACKOfoRecv           *float64
+	TCPAbortOnData            *float64
+	TCPAbortOnClose           *float64
+	TCPAbortOnMemory          *float64
+	TCPAbortOnTimeout         *float64
+	TCPAbortOnLinger          *float64
+	TCPAbortFailed            *float64
+	TCPMemoryPressures        *float64
+	TCPMemoryPressuresChrono  *float64
+	TCPSACKDiscard            *float64
+	TCPDSACKIgnoredOld        *float64
+	TCPDSACKIgnoredNoUndo     *float64
+	TCPSpuriousRTOs           *float64
+	TCPMD5NotFound            *float64
+	TCPMD5Unexpected          *float64
+	TCPMD5Failure             *float64
+	TCPSackShifted            *float64
+	TCPSackMerged             *float64
+	TCPSackShiftFallback      *float64
+	TCPBacklogDrop            *float64
+	PFMemallocDrop            *float64
+	TCPMinTTLDrop             *float64
+	TCPDeferAcceptDrop        *float64
+	IPReversePathFilter       *float64
+	TCPTimeWaitOverflow       *float64
+	TCPReqQFullDoCookies      *float64
+	TCPReqQFullDrop           *float64
+	TCPRetransFail            *float64
+	TCPRcvCoalesce            *float64
+	TCPRcvQDrop               *float64
+	TCPOFOQueue               *float64
+	TCPOFODrop                *float64
+	TCPOFOMerge               *float64
+	TCPChallengeACK           *float64
+	TCPSYNChallenge           *float64
+	TCPFastOpenActive         *float64
+	TCPFastOpenActiveFail     *float64
+	TCPFastOpenPassive        *float64
+	TCPFastOpenPassiveFail    *float64
+	TCPFastOpenListenOverflow *float64
+	TCPFastOpenCookieReqd     *float64
+	TCPFastOpenBlackhole      *float64
+	TCPSpuriousRtxHostQueues  *float64
+	BusyPollRxPackets         *float64
+	TCPAutoCorking            *float64
+	TCPFromZeroWindowAdv      *float64
+	TCPToZeroWindowAdv        *float64
+	TCPWantZeroWindowAdv      *float64
+	TCPSynRetrans             *float64
+	TCPOrigDataSent           *float64
+	TCPHystartTrainDetect     *float64
+	TCPHystartTrainCwnd       *float64
+	TCPHystartDelayDetect     *float64
+	TCPHystartDelayCwnd       *float64
+	TCPACKSkippedSynRecv      *float64
+	TCPACKSkippedPAWS         *float64
+	TCPACKSkippedSeq          *float64
+	TCPACKSkippedFinWait2     *float64
+	TCPACKSkippedTimeWait     *float64
+	TCPACKSkippedChallenge    *float64
+	TCPWinProbe               *float64
+	TCPKeepAlive              *float64
+	TCPMTUPFail               *float64
+	TCPMTUPSuccess            *float64
+	TCPWqueueTooBig           *float64
+}
+
+type IpExt struct { // nolint:revive
+	InNoRoutes      *float64
+	InTruncatedPkts *float64
+	InMcastPkts     *float64
+	OutMcastPkts    *float64
+	InBcastPkts     *float64
+	OutBcastPkts    *float64
+	InOctets        *float64
+	OutOctets       *float64
+	InMcastOctets   *float64
+	OutMcastOctets  *float64
+	InBcastOctets   *float64
+	OutBcastOctets  *float64
+	InCsumErrors    *float64
+	InNoECTPkts     *float64
+	InECT1Pkts      *float64
+	InECT0Pkts      *float64
+	InCEPkts        *float64
+	ReasmOverlaps   *float64
+}
+
+func (p Proc) Netstat() (ProcNetstat, error) {
+	filename := p.path("net/netstat")
+	data, err := util.ReadFileNoStat(filename)
+	if err != nil {
+		return ProcNetstat{PID: p.PID}, err
+	}
+	procNetstat, err := parseProcNetstat(bytes.NewReader(data), filename)
+	procNetstat.PID = p.PID
+	return procNetstat, err
+}
+
+// parseProcNetstat parses the metrics from proc/<pid>/net/netstat file
+// and returns a ProcNetstat structure.
+func parseProcNetstat(r io.Reader, fileName string) (ProcNetstat, error) {
+	var (
+		scanner     = bufio.NewScanner(r)
+		procNetstat = ProcNetstat{}
+	)
+
+	for scanner.Scan() {
+		nameParts := strings.Split(scanner.Text(), " ")
+		scanner.Scan()
+		valueParts := strings.Split(scanner.Text(), " ")
+		// Remove trailing :.
+		protocol := strings.TrimSuffix(nameParts[0], ":")
+		if len(nameParts) != len(valueParts) {
+			return procNetstat, fmt.Errorf("%w: mismatch field count mismatch in %s: %s",
+				ErrFileParse, fileName, protocol)
+		}
+		for i := 1; i < len(nameParts); i++ {
+			value, err := strconv.ParseFloat(valueParts[i], 64)
+			if err != nil {
+				return procNetstat, err
+			}
+			key := nameParts[i]
+
+			switch protocol {
+			case "TcpExt":
+				switch key {
+				case "SyncookiesSent":
+					procNetstat.TcpExt.SyncookiesSent = &value
+				case "SyncookiesRecv":
+					procNetstat.TcpExt.SyncookiesRecv = &value
+				case "SyncookiesFailed":
+					procNetstat.TcpExt.SyncookiesFailed = &value
+				case "EmbryonicRsts":
+					procNetstat.TcpExt.EmbryonicRsts = &value
+				case "PruneCalled":
+					procNetstat.TcpExt.PruneCalled = &value
+				case "RcvPruned":
+					procNetstat.TcpExt.RcvPruned = &value
+				case "OfoPruned":
+					procNetstat.TcpExt.OfoPruned = &value
+				case "OutOfWindowIcmps":
+					procNetstat.TcpExt.OutOfWindowIcmps = &value
+				case "LockDroppedIcmps":
+					procNetstat.TcpExt.LockDroppedIcmps = &value
+				case "ArpFilter":
+					procNetstat.TcpExt.ArpFilter = &value
+				case "TW":
+					procNetstat.TcpExt.TW = &value
+				case "TWRecycled":
+					procNetstat.TcpExt.TWRecycled = &value
+				case "TWKilled":
+					procNetstat.TcpExt.TWKilled = &value
+				case "PAWSActive":
+					procNetstat.TcpExt.PAWSActive = &value
+				case "PAWSEstab":
+					procNetstat.TcpExt.PAWSEstab = &value
+				case "DelayedACKs":
+					procNetstat.TcpExt.DelayedACKs = &value
+				case "DelayedACKLocked":
+					procNetstat.TcpExt.DelayedACKLocked = &value
+				case "DelayedACKLost":
+					procNetstat.TcpExt.DelayedACKLost = &value
+				case "ListenOverflows":
+					procNetstat.TcpExt.ListenOverflows = &value
+				case "ListenDrops":
+					procNetstat.TcpExt.ListenDrops = &value
+				case "TCPHPHits":
+					procNetstat.TcpExt.TCPHPHits = &value
+				case "TCPPureAcks":
+					procNetstat.TcpExt.TCPPureAcks = &value
+				case "TCPHPAcks":
+					procNetstat.TcpExt.TCPHPAcks = &value
+				case "TCPRenoRecovery":
+					procNetstat.TcpExt.TCPRenoRecovery = &value
+				case "TCPSackRecovery":
+					procNetstat.TcpExt.TCPSackRecovery = &value
+				case "TCPSACKReneging":
+					procNetstat.TcpExt.TCPSACKReneging = &value
+				case "TCPSACKReorder":
+					procNetstat.TcpExt.TCPSACKReorder = &value
+				case "TCPRenoReorder":
+					procNetstat.TcpExt.TCPRenoReorder = &value
+				case "TCPTSReorder":
+					procNetstat.TcpExt.TCPTSReorder = &value
+				case "TCPFullUndo":
+					procNetstat.TcpExt.TCPFullUndo = &value
+				case "TCPPartialUndo":
+					procNetstat.TcpExt.TCPPartialUndo = &value
+				case "TCPDSACKUndo":
+					procNetstat.TcpExt.TCPDSACKUndo = &value
+				case "TCPLossUndo":
+					procNetstat.TcpExt.TCPLossUndo = &value
+				case "TCPLostRetransmit":
+					procNetstat.TcpExt.TCPLostRetransmit = &value
+				case "TCPRenoFailures":
+					procNetstat.TcpExt.TCPRenoFailures = &value
+				case "TCPSackFailures":
+					procNetstat.TcpExt.TCPSackFailures = &value
+				case "TCPLossFailures":
+					procNetstat.TcpExt.TCPLossFailures = &value
+				case "TCPFastRetrans":
+					procNetstat.TcpExt.TCPFastRetrans = &value
+				case "TCPSlowStartRetrans":
+					procNetstat.TcpExt.TCPSlowStartRetrans = &value
+				case "TCPTimeouts":
+					procNetstat.TcpExt.TCPTimeouts = &value
+				case "TCPLossProbes":
+					procNetstat.TcpExt.TCPLossProbes = &value
+				case "TCPLossProbeRecovery":
+					procNetstat.TcpExt.TCPLossProbeRecovery = &value
+				case "TCPRenoRecoveryFail":
+					procNetstat.TcpExt.TCPRenoRecoveryFail = &value
+				case "TCPSackRecoveryFail":
+					procNetstat.TcpExt.TCPSackRecoveryFail = &value
+				case "TCPRcvCollapsed":
+					procNetstat.TcpExt.TCPRcvCollapsed = &value
+				case "TCPDSACKOldSent":
+					procNetstat.TcpExt.TCPDSACKOldSent = &value
+				case "TCPDSACKOfoSent":
+					procNetstat.TcpExt.TCPDSACKOfoSent = &value
+				case "TCPDSACKRecv":
+					procNetstat.TcpExt.TCPDSACKRecv = &value
+				case "TCPDSACKOfoRecv":
+					procNetstat.TcpExt.TCPDSACKOfoRecv = &value
+				case "TCPAbortOnData":
+					procNetstat.TcpExt.TCPAbortOnData = &value
+				case "TCPAbortOnClose":
+					procNetstat.TcpExt.TCPAbortOnClose = &value
+				case "TCPDeferAcceptDrop":
+					procNetstat.TcpExt.TCPDeferAcceptDrop = &value
+				case "IPReversePathFilter":
+					procNetstat.TcpExt.IPReversePathFilter = &value
+				case "TCPTimeWaitOverflow":
+					procNetstat.TcpExt.TCPTimeWaitOverflow = &value
+				case "TCPReqQFullDoCookies":
+					procNetstat.TcpExt.TCPReqQFullDoCookies = &value
+				case "TCPReqQFullDrop":
+					procNetstat.TcpExt.TCPReqQFullDrop = &value
+				case "TCPRetransFail":
+					procNetstat.TcpExt.TCPRetransFail = &value
+				case "TCPRcvCoalesce":
+					procNetstat.TcpExt.TCPRcvCoalesce = &value
+				case "TCPRcvQDrop":
+					procNetstat.TcpExt.TCPRcvQDrop = &value
+				case "TCPOFOQueue":
+					procNetstat.TcpExt.TCPOFOQueue = &value
+				case "TCPOFODrop":
+					procNetstat.TcpExt.TCPOFODrop = &value
+				case "TCPOFOMerge":
+					procNetstat.TcpExt.TCPOFOMerge = &value
+				case "TCPChallengeACK":
+					procNetstat.TcpExt.TCPChallengeACK = &value
+				case "TCPSYNChallenge":
+					procNetstat.TcpExt.TCPSYNChallenge = &value
+				case "TCPFastOpenActive":
+					procNetstat.TcpExt.TCPFastOpenActive = &value
+				case "TCPFastOpenActiveFail":
+					procNetstat.TcpExt.TCPFastOpenActiveFail = &value
+				case "TCPFastOpenPassive":
+					procNetstat.TcpExt.TCPFastOpenPassive = &value
+				case "TCPFastOpenPassiveFail":
+					procNetstat.TcpExt.TCPFastOpenPassiveFail = &value
+				case "TCPFastOpenListenOverflow":
+					procNetstat.TcpExt.TCPFastOpenListenOverflow = &value
+				case "TCPFastOpenCookieReqd":
+					procNetstat.TcpExt.TCPFastOpenCookieReqd = &value
+				case "TCPFastOpenBlackhole":
+					procNetstat.TcpExt.TCPFastOpenBlackhole = &value
+				case "TCPSpuriousRtxHostQueues":
+					procNetstat.TcpExt.TCPSpuriousRtxHostQueues = &value
+				case "BusyPollRxPackets":
+					procNetstat.TcpExt.BusyPollRxPackets = &value
+				case "TCPAutoCorking":
+					procNetstat.TcpExt.TCPAutoCorking = &value
+				case "TCPFromZeroWindowAdv":
+					procNetstat.TcpExt.TCPFromZeroWindowAdv = &value
+				case "TCPToZeroWindowAdv":
+					procNetstat.TcpExt.TCPToZeroWindowAdv = &value
+				case "TCPWantZeroWindowAdv":
+					procNetstat.TcpExt.TCPWantZeroWindowAdv = &value
+				case "TCPSynRetrans":
+					procNetstat.TcpExt.TCPSynRetrans = &value
+				case "TCPOrigDataSent":
+					procNetstat.TcpExt.TCPOrigDataSent = &value
+				case "TCPHystartTrainDetect":
+					procNetstat.TcpExt.TCPHystartTrainDetect = &value
+				case "TCPHystartTrainCwnd":
+					procNetstat.TcpExt.TCPHystartTrainCwnd = &value
+				case "TCPHystartDelayDetect":
+					procNetstat.TcpExt.TCPHystartDelayDetect = &value
+				case "TCPHystartDelayCwnd":
+					procNetstat.TcpExt.TCPHystartDelayCwnd = &value
+				case "TCPACKSkippedSynRecv":
+					procNetstat.TcpExt.TCPACKSkippedSynRecv = &value
+				case "TCPACKSkippedPAWS":
+					procNetstat.TcpExt.TCPACKSkippedPAWS = &value
+				case "TCPACKSkippedSeq":
+					procNetstat.TcpExt.TCPACKSkippedSeq = &value
+				case "TCPACKSkippedFinWait2":
+					procNetstat.TcpExt.TCPACKSkippedFinWait2 = &value
+				case "TCPACKSkippedTimeWait":
+					procNetstat.TcpExt.TCPACKSkippedTimeWait = &value
+				case "TCPACKSkippedChallenge":
+					procNetstat.TcpExt.TCPACKSkippedChallenge = &value
+				case "TCPWinProbe":
+					procNetstat.TcpExt.TCPWinProbe = &value
+				case "TCPKeepAlive":
+					procNetstat.TcpExt.TCPKeepAlive = &value
+				case "TCPMTUPFail":
+					procNetstat.TcpExt.TCPMTUPFail = &value
+				case "TCPMTUPSuccess":
+					procNetstat.TcpExt.TCPMTUPSuccess = &value
+				case "TCPWqueueTooBig":
+					procNetstat.TcpExt.TCPWqueueTooBig = &value
+				}
+			case "IpExt":
+				switch key {
+				case "InNoRoutes":
+					procNetstat.IpExt.InNoRoutes = &value
+				case "InTruncatedPkts":
+					procNetstat.IpExt.InTruncatedPkts = &value
+				case "InMcastPkts":
+					procNetstat.IpExt.InMcastPkts = &value
+				case "OutMcastPkts":
+					procNetstat.IpExt.OutMcastPkts = &value
+				case "InBcastPkts":
+					procNetstat.IpExt.InBcastPkts = &value
+				case "OutBcastPkts":
+					procNetstat.IpExt.OutBcastPkts = &value
+				case "InOctets":
+					procNetstat.IpExt.InOctets = &value
+				case "OutOctets":
+					procNetstat.IpExt.OutOctets = &value
+				case "InMcastOctets":
+					procNetstat.IpExt.InMcastOctets = &value
+				case "OutMcastOctets":
+					procNetstat.IpExt.OutMcastOctets = &value
+				case "InBcastOctets":
+					procNetstat.IpExt.InBcastOctets = &value
+				case "OutBcastOctets":
+					procNetstat.IpExt.OutBcastOctets = &value
+				case "InCsumErrors":
+					procNetstat.IpExt.InCsumErrors = &value
+				case "InNoECTPkts":
+					procNetstat.IpExt.InNoECTPkts = &value
+				case "InECT1Pkts":
+					procNetstat.IpExt.InECT1Pkts = &value
+				case "InECT0Pkts":
+					procNetstat.IpExt.InECT0Pkts = &value
+				case "InCEPkts":
+					procNetstat.IpExt.InCEPkts = &value
+				case "ReasmOverlaps":
+					procNetstat.IpExt.ReasmOverlaps = &value
+				}
+			}
+		}
+	}
+	return procNetstat, scanner.Err()
+}