add prometheus and counter for testing

Dockerfile

@@ -64,6 +64,7 @@ RUN cd /app/src/autograph/tools/makecsr && go build -o /go/bin/makecsr .
 #------------------------------------------------------------------------------
 FROM prebuild
 EXPOSE 8000
+EXPOSE 2112
 
 # Copy compiled appliation from the builder.
 ADD . /app/src/autograph

autograph.yaml

@@ -11,6 +11,9 @@ statsd:
     namespace: "autograph."
     buflen: 1
 
+debugserver:
+    listen: "0.0.0.0:2112"
+
 # When using an HSM, place the path to the pkcs11 client library,
 # token label and pin of the crypto user in the configuration below
 # hsm:

docker-compose.yml

@@ -27,6 +27,7 @@ services:
       - db
     ports:
       - "8000:8000"
+      - "2112:2112"
     volumes:
       - apptmpdir:/tmp/
     healthcheck:
@@ -116,7 +117,4 @@ services:
       - db
     user: "0"
     working_dir: "/app/src/autograph/"
-    command:
-      [
-        "./bin/run_unit_tests.sh"
-      ]
+    command: ["./bin/run_unit_tests.sh"]

go.mod

@@ -17,6 +17,7 @@ require (
 	github.com/lib/pq v1.10.9
 	github.com/miekg/pkcs11 v1.0.3
 	github.com/mozilla-services/yaml v0.0.0-20191106225358-5c216288813c
+	github.com/prometheus/client_golang v1.20.5
 	github.com/sirupsen/logrus v1.9.3
 	github.com/youtube/vitess v2.1.1+incompatible
 	go.mozilla.org/cose v0.0.0-20200221144611-2ea72a6b3de3
@@ -66,6 +67,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.28.8 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.33.6 // indirect
 	github.com/aws/smithy-go v1.22.1 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/blang/semver v3.5.1+incompatible // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
 	github.com/census-instrumentation/opencensus-proto v0.4.1 // indirect
@@ -98,15 +100,20 @@ require (
 	github.com/hashicorp/go-sockaddr v1.0.7 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/hashicorp/vault/api v1.15.0 // indirect
+	github.com/klauspost/compress v1.17.9 // indirect
 	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
 	github.com/mitchellh/go-wordwrap v1.0.1 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/pkg/browser v0.0.0-20240102092130-5ac0b6a4141c // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 // indirect
+	github.com/prometheus/client_model v0.6.1 // indirect
+	github.com/prometheus/common v0.55.0 // indirect
+	github.com/prometheus/procfs v0.15.1 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/ryanuber/go-glob v1.0.0 // indirect
 	github.com/ugorji/go v0.0.0-20180112141927-9831f2c3ac10 // indirect

go.sum

@@ -106,6 +106,8 @@ github.com/aws/aws-sdk-go-v2/service/sts v1.33.6 h1:VwhTrsTuVn52an4mXx29PqRzs2Dv
 github.com/aws/aws-sdk-go-v2/service/sts v1.33.6/go.mod h1:+8h7PZb3yY5ftmVLD7ocEoE98hdc8PoKS0H3wfx1dlc=
 github.com/aws/smithy-go v1.22.1 h1:/HPHZQ0g7f4eUeK6HKglFz8uwVfZKgoI25rb/J+dnro=
 github.com/aws/smithy-go v1.22.1/go.mod h1:irrKGvNn1InZwb2d7fkIRNucdfwR8R+Ts3wxYa/cJHg=
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/blang/semver v3.5.1+incompatible h1:cQNTCjp13qL8KC3Nbxr/y2Bqb63oX6wdnnjpJbkM4JQ=
 github.com/blang/semver v3.5.1+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
@@ -216,6 +218,8 @@ github.com/hashicorp/vault/api v1.15.0 h1:O24FYQCWwhwKnF7CuSqP30S51rTV7vz1iACXE/
 github.com/hashicorp/vault/api v1.15.0/go.mod h1:+5YTO09JGn0u+b6ySD/LLVf8WkJCPLAL2Vkmrn2+CM8=
 github.com/keybase/go-keychain v0.0.0-20231219164618-57a3676c3af6 h1:IsMZxCuZqKuao2vNdfD82fjjgPLfyHLpR41Z88viRWs=
 github.com/keybase/go-keychain v0.0.0-20231219164618-57a3676c3af6/go.mod h1:3VeWNIJaW+O5xpRQbPp0Ybqu1vJd/pm7s2F473HRrkw=
+github.com/klauspost/compress v1.17.9 h1:6KIumPrER1LHsvBVuDa0r5xaG0Es51mhhB9BQB2qeMA=
+github.com/klauspost/compress v1.17.9/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
@@ -245,6 +249,8 @@ github.com/moby/term v0.5.0 h1:xt8Q1nalod/v7BqbG21f8mQPqH+xAaC9C3N3wfWbVP0=
 github.com/moby/term v0.5.0/go.mod h1:8FzsFHVUBGZdbDsJw/ot+X+d5HLUbvklYLJ9uGfcI3Y=
 github.com/mozilla-services/yaml v0.0.0-20191106225358-5c216288813c h1:yE1NxRAZA3wF0laDWECtOe2J0tFjSHUI6MXXbMif+QY=
 github.com/mozilla-services/yaml v0.0.0-20191106225358-5c216288813c/go.mod h1:Is/Ucts/yU/mWyGR8yELRoO46mejouKsJfQLAIfTR18=
+github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
+github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/opencontainers/go-digest v1.0.0 h1:apOUWs51W5PlhuyGyz9FCeeBIOUDA/6nW8Oi/yOhh5U=
 github.com/opencontainers/go-digest v1.0.0/go.mod h1:0JzlMkj0TRzQZfJkVvzbP0HBR3IKzErnv2BNG4W4MAM=
 github.com/opencontainers/image-spec v1.1.0 h1:8SG7/vwALn54lVB/0yZ/MMwhFrPYtpEHQb2IpWsCzug=
@@ -262,6 +268,14 @@ github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10 h1:GFCKgm
 github.com/planetscale/vtprotobuf v0.6.1-0.20240319094008-0393e58bdf10/go.mod h1:t/avpk3KcrXxUnYOhZhMXJlSEyie6gQbtLq5NM3loB8=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/prometheus/client_golang v1.20.5 h1:cxppBPuYhUnsO6yo/aoRol4L7q7UFfdm+bR9r+8l63Y=
+github.com/prometheus/client_golang v1.20.5/go.mod h1:PIEt8X02hGcP8JWbeHyeZ53Y/jReSnHgO035n//V5WE=
+github.com/prometheus/client_model v0.6.1 h1:ZKSh/rekM+n3CeS952MLRAdFwIKqeY8b62p8ais2e9E=
+github.com/prometheus/client_model v0.6.1/go.mod h1:OrxVMOVHjw3lKMa8+x6HeMGkHMQyHDk9E3jmP2AmGiY=
+github.com/prometheus/common v0.55.0 h1:KEi6DK7lXW/m7Ig5i47x0vRzuBsHuvJdi5ee6Y3G1dc=
+github.com/prometheus/common v0.55.0/go.mod h1:2SECS4xJG1kd8XF9IcM1gMX6510RAEL65zxzNImwdc8=
+github.com/prometheus/procfs v0.15.1 h1:YagwOFzUgYfKKHX6Dr+sHT7km/hxC76UB0learggepc=
+github.com/prometheus/procfs v0.15.1/go.mod h1:fB45yRUv8NstnjriLhBQLuOUt+WW4BsoGhij/e3PBqk=
 github.com/redis/go-redis/v9 v9.6.1 h1:HHDteefn6ZkTtY5fGUE8tj8uy85AHk6zP7CpzIAM0y4=
 github.com/redis/go-redis/v9 v9.6.1/go.mod h1:0C0c6ycQsdpVNQpxb1njEQIqkx5UcsM8FJCQLgE9+RA=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=

main.go

@@ -43,6 +43,7 @@ import (
 
 	"github.com/DataDog/datadog-go/v5/statsd"
 	"github.com/mozilla-services/autograph/crypto11"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 // configuration loads a yaml file that contains the configuration of Autograph
@@ -59,6 +60,11 @@ type configuration struct {
 		Namespace string
 		Buflen    int
 	}
+
+	// DebugServer are the settings for the control plane HTTP server where
+	// metrics are exposed for collection and some limited utitilites can live.
+	DebugServer debugServerConfig `yaml:"debugserver"`
+
 	HSM                   crypto11.PKCS11Config
 	Database              database.Config
 	Signers               []signer.Configuration
@@ -69,6 +75,12 @@ type configuration struct {
 	MonitorInterval       time.Duration
 }
 
+type debugServerConfig struct {
+	// Listen is a TCP address for the HTTP server to listen on. See
+	// http.Server's Addr field for details.
+	Listen string `yaml:"listen"`
+}
+
 // An autographer is a running instance of an autograph service,
 // with all signers and permissions configured
 type autographer struct {
@@ -240,6 +252,29 @@ func run(conf configuration, listen string, debug bool) {
 		router.PathPrefix(prefix).Handler(http.StripPrefix(prefix, http.FileServer(http.Dir(parsedURL.Path))))
 	}
 
+	ag.stats.Incr(foobarTestCounterName, nil, 1)
+	foobarTestCounter.Inc()
+
+	if conf.DebugServer.Listen != "" {
+		log.Infof("starting debug server on %s", conf.DebugServer.Listen)
+		go func() {
+			mux := mux.NewRouter()
+			mux.Handle("/metrics", promhttp.Handler())
+			srv := http.Server{
+				Addr:         conf.DebugServer.Listen,
+				IdleTimeout:  conf.Server.IdleTimeout,
+				ReadTimeout:  conf.Server.ReadTimeout,
+				WriteTimeout: conf.Server.WriteTimeout,
+				Handler:      mux,
+			}
+
+			err := srv.ListenAndServe()
+			if err != nil {
+				log.Fatalf("unable to start up debug server on %s: %s", conf.DebugServer.Listen, err)
+			}
+		}()
+	}
+
 	server := &http.Server{
 		IdleTimeout:  conf.Server.IdleTimeout,
 		ReadTimeout:  conf.Server.ReadTimeout,

stats.go

@@ -6,9 +6,21 @@ import (
 	"sync/atomic"
 
 	"github.com/DataDog/datadog-go/v5/statsd"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
 	log "github.com/sirupsen/logrus"
 )
 
+var (
+	// TODO(AUT-393): remove the statsd and prometheus counter using this name
+	// once we're done testing.
+	foobarTestCounterName = "foobar_test"
+	foobarTestCounter     = promauto.NewCounter(prometheus.CounterOpts{
+		Name: foobarTestCounterName,
+		Help: "A counter used for testing how prometheus and statsd metrics differ",
+	})
+)
+
 func loadStatsd(conf configuration) (*statsd.Client, error) {
 	statsdClient, err := statsd.New(conf.Statsd.Addr, statsd.WithNamespace(conf.Statsd.Namespace))
 	if err != nil {