add custom build metrics (#90)

add  build metrics

---------

Signed-off-by: Pablo Chacin <[email protected]>

README.md

@@ -25,6 +25,18 @@ See [k6catalog](http://github.com/grafana/k6catalog) for more details on definin
 
 The default catalog is defined at https://registry.k6.io/catalog.json
 
+## Metrics
+
+The k6build's [builder](pkg/builder/builder.go) collects metrics about the build process in a prometheus compatible format:
+* Number of build requests
+* Number of build requests satisfied from the object store
+* Number of build requests that could not be satisfied (e.g dependency not supported)
+* Number of builds
+* Number of failed build processes
+* Build time histogram
+
+
+The k6build [server](cmd/server/server.go) exposes these metrics in the `/metrics` path.
 
 ## Usage scenarios
 

cmd/server/server.go

@@ -15,6 +15,9 @@ import (
 	"github.com/grafana/k6build/pkg/store/client"
 	"github.com/grafana/k6build/pkg/store/s3"
 
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+
 	"github.com/spf13/cobra"
 )
 
@@ -159,8 +162,9 @@ func New() *cobra.Command { //nolint:funlen
 					Verbose:           verbose,
 					AllowBuildSemvers: allowBuildSemvers,
 				},
-				Catalog: catalog,
-				Store:   store,
+				Catalog:    catalog,
+				Store:      store,
+				Registerer: prometheus.DefaultRegisterer,
 			}
 			buildSrv, err := builder.New(cmd.Context(), config)
 			if err != nil {
@@ -176,6 +180,9 @@ func New() *cobra.Command { //nolint:funlen
 			srv := http.NewServeMux()
 			srv.Handle("POST /build", http.StripPrefix("/build", buildAPI))
 
+			// serve metrics
+			srv.Handle("/metrics", promhttp.Handler())
+
 			listerAddr := fmt.Sprintf("0.0.0.0:%d", port)
 			log.Info("starting server", "address", listerAddr)
 			err = http.ListenAndServe(listerAddr, srv) //nolint:gosec

go.mod

@@ -33,7 +33,9 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.28.10 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.33.9 // indirect
 	github.com/aws/smithy-go v1.22.1 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cenkalti/backoff/v4 v4.2.1 // indirect
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/containerd/containerd v1.7.18 // indirect
 	github.com/containerd/log v0.1.0 // indirect
 	github.com/containerd/platforms v0.2.1 // indirect
@@ -48,7 +50,8 @@ require (
 	github.com/go-ole/go-ole v1.3.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/google/uuid v1.6.0 // indirect
-	github.com/klauspost/compress v1.17.7 // indirect
+	github.com/klauspost/compress v1.17.9 // indirect
+	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20240226150601-1dcf7310316a // indirect
 	github.com/magiconair/properties v1.8.7 // indirect
 	github.com/moby/docker-image-spec v1.3.1 // indirect
@@ -57,11 +60,15 @@ require (
 	github.com/moby/sys/user v0.1.0 // indirect
 	github.com/moby/term v0.5.0 // indirect
 	github.com/morikuni/aec v1.0.0 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/opencontainers/image-spec v1.1.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/power-devops/perfstat v0.0.0-20240221224432-82ca36839d55 // 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/shirou/gopsutil/v3 v3.24.2 // indirect
 	github.com/shoenig/go-m1cpu v0.1.6 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
@@ -76,12 +83,14 @@ require (
 	go.opentelemetry.io/otel/trace v1.24.0 // indirect
 	golang.org/x/crypto v0.31.0 // indirect
 	golang.org/x/sys v0.28.0 // indirect
+	google.golang.org/protobuf v1.34.2 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
 
 require (
 	github.com/google/go-cmp v0.6.0
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/prometheus/client_golang v1.20.5
 	github.com/spf13/pflag v1.0.5 // indirect
 	golang.org/x/mod v0.21.0 // indirect
 )

go.sum

@@ -44,8 +44,12 @@ github.com/aws/aws-sdk-go-v2/service/sts v1.33.9 h1:BRVDbewN6VZcwr+FBOszDKvYeXY1
 github.com/aws/aws-sdk-go-v2/service/sts v1.33.9/go.mod h1:f6vjfZER1M17Fokn0IzssOTMT2N8ZSq+7jnNF0tArvw=
 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/cenkalti/backoff/v4 v4.2.1 h1:y4OZtCnogmCPw98Zjyt5a6+QwPLGkiQsYW5oUqylYbM=
 github.com/cenkalti/backoff/v4 v4.2.1/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
+github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
+github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/containerd/containerd v1.7.18 h1:jqjZTQNfXGoEaZdW1WwPU0RqSn1Bm2Ay/KJPUuO8nao=
 github.com/containerd/containerd v1.7.18/go.mod h1:IYEk9/IO6wAPUz2bCMVUbsfXjzw5UNP5fLz4PsUygQ4=
 github.com/containerd/log v0.1.0 h1:TCJt7ioM2cr/tfR8GPbGf9/VRAX8D2B4PjzCpfX540I=
@@ -96,12 +100,14 @@ github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
-github.com/klauspost/compress v1.17.7 h1:ehO88t2UGzQK66LMdE8tibEd1ErmzZjNEqWkjLAKQQg=
-github.com/klauspost/compress v1.17.7/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
-github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0=
-github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk=
+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=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
+github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0/go.mod h1:zJYVVT2jmtg6P3p1VtQj7WsuWi/y4VnjVBn7F8KPB3I=
 github.com/lufia/plan9stats v0.0.0-20240226150601-1dcf7310316a h1:3Bm7EwfUQUvhNeKIkUct/gl9eod1TcXuj8stxvi/GoI=
 github.com/lufia/plan9stats v0.0.0-20240226150601-1dcf7310316a/go.mod h1:ilwx/Dta8jXAgpFYFvSWEMwxmbWXyiUHkd5FwyKhb5k=
@@ -119,6 +125,8 @@ 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/morikuni/aec v1.0.0 h1:nP9CBfwrvYnBRgY6qfDQkygYDmYwOilePFkwzv4dU8A=
 github.com/morikuni/aec v1.0.0/go.mod h1:BbKIizmSmc5MMPqRYbxO4ZU0S0+P200+tUnFx7PXmsc=
+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=
@@ -130,8 +138,16 @@ github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZN
 github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c/go.mod h1:OmDBASR4679mdNQnz2pUhc2G8CO2JrUAVFDRBDP/hJE=
 github.com/power-devops/perfstat v0.0.0-20240221224432-82ca36839d55 h1:o4JXh1EVt9k/+g42oCprj/FisM4qX9L3sZB3upGN2ZU=
 github.com/power-devops/perfstat v0.0.0-20240221224432-82ca36839d55/go.mod h1:OmDBASR4679mdNQnz2pUhc2G8CO2JrUAVFDRBDP/hJE=
-github.com/rogpeppe/go-internal v1.8.1 h1:geMPLpDpQOgVyCg5z5GoRwLHepNdb71NXb67XFkP+Eg=
-github.com/rogpeppe/go-internal v1.8.1/go.mod h1:JeRgkft04UBgHMgCIwADu4Pn6Mtm5d4nPKWu0nJ5d+o=
+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/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
+github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/shirou/gopsutil/v3 v3.24.2 h1:kcR0erMbLg5/3LcInpw0X/rrPSqq4CDPyI6A6ZRC18Y=
 github.com/shirou/gopsutil/v3 v3.24.2/go.mod h1:tSg/594BcA+8UdQU2XcW803GWYgdtauFFPgJCJKZlVk=
@@ -229,8 +245,6 @@ golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGm
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20200619180055-7c47624df98f/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
-golang.org/x/tools v0.13.0 h1:Iey4qkscZuv0VvIt8E0neZjtPVQFSc870HQ448QgEmQ=
-golang.org/x/tools v0.13.0/go.mod h1:HvlwmtVNQAhOuCjW7xxvovg8wbNq7LwfXh/k7wXUl58=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
@@ -242,8 +256,8 @@ google.golang.org/genproto/googleapis/rpc v0.0.0-20240318140521-94a12d6c2237 h1:
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240318140521-94a12d6c2237/go.mod h1:WtryC6hu0hhx87FDGxWCDptyssuo68sk10vYjF+T9fY=
 google.golang.org/grpc v1.64.1 h1:LKtvyfbX3UGVPFcGqJ9ItpVWW6oN/2XqTxfAnwRRXiA=
 google.golang.org/grpc v1.64.1/go.mod h1:hiQF4LFZelK2WKaP6W0L92zGHtiQdZxk8CrSdvyjeP0=
-google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
-google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
+google.golang.org/protobuf v1.34.2 h1:6xV6lTsCfpGD21XK49h7MhtcApnLqkfYgPcdHftf6hg=
+google.golang.org/protobuf v1.34.2/go.mod h1:qYOHts0dSfpeUzUFpOMr/WGzszTmLH+DiWniOlNbLDw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=

pkg/builder/builder.go

@@ -16,6 +16,8 @@ import (
 	"github.com/grafana/k6build/pkg/catalog"
 	"github.com/grafana/k6build/pkg/store"
 	"github.com/grafana/k6foundry"
+
+	"github.com/prometheus/client_golang/prometheus"
 )
 
 const (
@@ -65,10 +67,11 @@ type Opts struct {
 
 // Config defines the configuration for a Builder
 type Config struct {
-	Opts    Opts
-	Catalog catalog.Catalog
-	Store   store.ObjectStore
-	Foundry Foundry
+	Opts       Opts
+	Catalog    catalog.Catalog
+	Store      store.ObjectStore
+	Foundry    Foundry
+	Registerer prometheus.Registerer
 }
 
 // Builder implements the BuildService interface
@@ -78,6 +81,7 @@ type Builder struct {
 	store   store.ObjectStore
 	mutexes sync.Map
 	foundry Foundry
+	metrics *metrics
 }
 
 // New returns a new instance of Builder given a BuilderConfig
@@ -94,11 +98,21 @@ func New(_ context.Context, config Config) (*Builder, error) {
 	if foundry == nil {
 		foundry = FoundryFunction(k6foundry.NewNativeBuilder)
 	}
+
+	metrics := newMetrics()
+	if config.Registerer != nil {
+		err := metrics.register(config.Registerer)
+		if err != nil {
+			return nil, k6build.NewWrappedError(ErrInitializingBuilder, err)
+		}
+	}
+
 	return &Builder{
 		catalog: config.Catalog,
 		opts:    config.Opts,
 		store:   config.Store,
 		foundry: foundry,
+		metrics: metrics,
 	}, nil
 }
 
@@ -108,7 +122,17 @@ func (b *Builder) Build( //nolint:funlen
 	platform string,
 	k6Constrains string,
 	deps []k6build.Dependency,
-) (k6build.Artifact, error) {
+) (artifact k6build.Artifact, buildErr error) {
+	// FIXME: this is a temporary solution because the logic has many paths that return
+	// an invalid parameters error and we need to increment the metrics in all of them
+	defer func() {
+		if errors.Is(buildErr, ErrInvalidParameters) {
+			b.metrics.buildsInvalidCounter.Inc()
+		}
+	}()
+
+	b.metrics.requestCounter.Inc()
+
 	buildPlatform, err := k6foundry.ParsePlatform(platform)
 	if err != nil {
 		return k6build.Artifact{}, k6build.NewWrappedError(ErrInvalidParameters, err)
@@ -167,6 +191,8 @@ func (b *Builder) Build( //nolint:funlen
 
 	artifactObject, err := b.store.Get(ctx, id)
 	if err == nil {
+		b.metrics.storeHitsCounter.Inc()
+
 		return k6build.Artifact{
 			ID:           id,
 			Checksum:     artifactObject.Checksum,
@@ -204,13 +230,18 @@ func (b *Builder) Build( //nolint:funlen
 	if err != nil {
 		return k6build.Artifact{}, k6build.NewWrappedError(ErrInitializingBuilder, err)
 	}
+	b.metrics.buildCounter.Inc()
+	buildTimer := prometheus.NewTimer(b.metrics.buildTimeHistogram)
 
 	artifactBuffer := &bytes.Buffer{}
 	buildInfo, err := builder.Build(ctx, buildPlatform, k6Mod.Version, mods, []string{}, artifactBuffer)
 	if err != nil {
+		b.metrics.buildsFailedCounter.Inc()
 		return k6build.Artifact{}, k6build.NewWrappedError(ErrAccessingArtifact, err)
 	}
 
+	buildTimer.ObserveDuration()
+
 	// if the version has a build metadata, we must use the actual version built
 	// TODO: check this version is supported
 	if buildMetadata != "" {