[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, 64 insertions, 0 deletions

diff --git a/vendor/github.com/prometheus/procfs/net_tcp.go b/vendor/github.com/prometheus/procfs/net_tcp.go
new file mode 100644
index 000000000..527762955
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/net_tcp.go
@@ -0,0 +1,64 @@
+// Copyright 2020 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
+
+type (
+	// NetTCP represents the contents of /proc/net/tcp{,6} file without the header.
+	NetTCP []*netIPSocketLine
+
+	// NetTCPSummary provides already computed values like the total queue lengths or
+	// the total number of used sockets. In contrast to NetTCP it does not collect
+	// the parsed lines into a slice.
+	NetTCPSummary NetIPSocketSummary
+)
+
+// NetTCP returns the IPv4 kernel/networking statistics for TCP datagrams
+// read from /proc/net/tcp.
+func (fs FS) NetTCP() (NetTCP, error) {
+	return newNetTCP(fs.proc.Path("net/tcp"))
+}
+
+// NetTCP6 returns the IPv6 kernel/networking statistics for TCP datagrams
+// read from /proc/net/tcp6.
+func (fs FS) NetTCP6() (NetTCP, error) {
+	return newNetTCP(fs.proc.Path("net/tcp6"))
+}
+
+// NetTCPSummary returns already computed statistics like the total queue lengths
+// for TCP datagrams read from /proc/net/tcp.
+func (fs FS) NetTCPSummary() (*NetTCPSummary, error) {
+	return newNetTCPSummary(fs.proc.Path("net/tcp"))
+}
+
+// NetTCP6Summary returns already computed statistics like the total queue lengths
+// for TCP datagrams read from /proc/net/tcp6.
+func (fs FS) NetTCP6Summary() (*NetTCPSummary, error) {
+	return newNetTCPSummary(fs.proc.Path("net/tcp6"))
+}
+
+// newNetTCP creates a new NetTCP{,6} from the contents of the given file.
+func newNetTCP(file string) (NetTCP, error) {
+	n, err := newNetIPSocket(file)
+	n1 := NetTCP(n)
+	return n1, err
+}
+
+func newNetTCPSummary(file string) (*NetTCPSummary, error) {
+	n, err := newNetIPSocketSummary(file)
+	if n == nil {
+		return nil, err
+	}
+	n1 := NetTCPSummary(*n)
+	return &n1, err
+}