Define dependencies for web. stack concretely.

This commit destroys the use of AppState, which makes passing
concrete state along to various serving components onerous.

.gitignore

@@ -21,5 +21,11 @@ _cgo_*
 core
 
 *-stamp
-prometheus.build
 prometheus
+
+.#*
+command-line-arguments.test
+*BACKUP*
+*BASE*
+*LOCAL*
+*REMOTE*

Makefile

@@ -11,36 +11,19 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-.SUFFIXES:
-
-TEST_ARTIFACTS = prometheus prometheus.build search_index
+TEST_ARTIFACTS = prometheus search_index
 
 include Makefile.INCLUDE
 
-REV        := $(shell git rev-parse --short HEAD)
-BRANCH     := $(shell git rev-parse --abbrev-ref HEAD)
-HOSTNAME   := $(shell hostname -f)
-BUILD_DATE := $(shell date +%Y%m%d-%H:%M:%S)
-BUILDFLAGS := -ldflags \
-	      " -X main.buildVersion $(REV)\
-		-X main.buildBranch $(BRANCH)\
-		-X main.buildUser $(USER)@$(HOSTNAME)\
-		-X main.buildDate $(BUILD_DATE)\
-		-X main.goVersion $(GO_VERSION)\
-		-X main.leveldbVersion $(LEVELDB_VERSION)\
-		-X main.protobufVersion $(PROTOCOL_BUFFERS_VERSION)\
-		-X main.snappyVersion $(SNAPPY_VERSION)"
-
 all: test
 
 advice:
 	go tool vet .
 
 binary: build
-	go build $(BUILDFLAGS) -o prometheus.build
+	go build $(BUILDFLAGS) .
 
 build: preparation config model web
-	go build $(BUILDFLAGS) .
 
 clean:
 	$(MAKE) -C build clean
@@ -72,11 +55,14 @@ preparation: source_path
 	$(MAKE) -C build
 
 run: binary
-	./prometheus.build $(ARGUMENTS)
+	./prometheus $(ARGUMENTS)
 
 search_index:
 	godoc -index -write_index -index_files='search_index'
 
+server: config model preparation
+	$(MAKE) -C server
+
 # source_path is responsible for ensuring that the builder has not done anything
 # stupid like working on Prometheus outside of ${GOPATH}.
 source_path:
@@ -84,15 +70,7 @@ source_path:
 	[ -d "$(FULL_GOPATH)" ]
 
 test: build
-	go test ./appstate/... $(GO_TEST_FLAGS)
-	go test ./coding/... $(GO_TEST_FLAGS)
-	go test ./config/... $(GO_TEST_FLAGS)
-	go test ./model/... $(GO_TEST_FLAGS)
-	go test ./retrieval/... $(GO_TEST_FLAGS)
-	go test ./rules/... $(GO_TEST_FLAGS)
-	go test ./storage/... $(GO_TEST_FLAGS)
-	go test ./utility/... $(GO_TEST_FLAGS)
-	go test ./web/... $(GO_TEST_FLAGS)
+	go test ./... $(GO_TEST_FLAGS)
 
 web: preparation config model
 	$(MAKE) -C web

Makefile.INCLUDE

@@ -1,3 +1,5 @@
+# -*- Mode: makefile -*-
+
 # Copyright 2013 Prometheus Team
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -52,3 +54,17 @@ BREW_INSTALL := brew install
 # By default, wget sets the creation time to match the server's, which throws
 # off Make.  :-(
 WGET := wget --no-use-server-timestamps -c
+
+REV        := $(shell git rev-parse --short HEAD)
+BRANCH     := $(shell git rev-parse --abbrev-ref HEAD)
+HOSTNAME   := $(shell hostname -f)
+BUILD_DATE := $(shell date +%Y%m%d-%H:%M:%S)
+BUILDFLAGS := -ldflags \
+	      " -X main.buildVersion $(REV)\
+		-X main.buildBranch $(BRANCH)\
+		-X main.buildUser $(USER)@$(HOSTNAME)\
+		-X main.buildDate $(BUILD_DATE)\
+		-X main.goVersion $(GO_VERSION)\
+		-X main.leveldbVersion $(LEVELDB_VERSION)\
+		-X main.protobufVersion $(PROTOCOL_BUFFERS_VERSION)\
+		-X main.snappyVersion $(SNAPPY_VERSION)"

appstate/appstate.go

@@ -1,33 +0,0 @@
-// Copyright 2013 Prometheus Team
-// 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 appstate
-
-import (
-	"github.com/prometheus/prometheus/config"
-	"github.com/prometheus/prometheus/retrieval"
-	"github.com/prometheus/prometheus/rules"
-	"github.com/prometheus/prometheus/storage/metric"
-)
-
-// ApplicationState is an encapsulation of all relevant Prometheus application
-// runtime state. It enables simpler passing of this state to components that
-// require it.
-type ApplicationState struct {
-	Config        config.Config
-	RuleManager   rules.RuleManager
-	Storage       metric.TieredStorage
-	TargetManager retrieval.TargetManager
-	BuildInfo     map[string]string
-	CurationState chan metric.CurationState
-}

main.go

@@ -15,7 +15,6 @@ package main
 
 import (
 	"flag"
-	"github.com/prometheus/prometheus/appstate"
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/retrieval"
 	"github.com/prometheus/prometheus/retrieval/format"
@@ -23,6 +22,7 @@ import (
 	"github.com/prometheus/prometheus/rules/ast"
 	"github.com/prometheus/prometheus/storage/metric"
 	"github.com/prometheus/prometheus/web"
+	"github.com/prometheus/prometheus/web/api"
 	"log"
 	"os"
 	"os/signal"
@@ -42,10 +42,10 @@ var (
 )
 
 type prometheus struct {
-	storage metric.TieredStorage
-	// TODO: Refactor channels to work with arrays of results for better chunking.
-	scrapeResults chan format.Result
+	curationState chan metric.CurationState
 	ruleResults   chan *rules.Result
+	storage       metric.TieredStorage
+	scrapeResults chan format.Result
 }
 
 func (p prometheus) interruptHandler() {
@@ -60,9 +60,8 @@ func (p prometheus) interruptHandler() {
 }
 
 func (p prometheus) close() {
+	close(p.curationState)
 	p.storage.Close()
-	close(p.scrapeResults)
-	close(p.ruleResults)
 }
 
 func main() {
@@ -92,22 +91,46 @@ func main() {
 
 	scrapeResults := make(chan format.Result, *scrapeResultsQueueCapacity)
 	ruleResults := make(chan *rules.Result, *ruleResultsQueueCapacity)
+	curationState := make(chan metric.CurationState, 1)
+
+	// Queue depth will need to be exposed
+	targetManager := retrieval.NewTargetManager(scrapeResults, *concurrentRetrievalAllowance)
+	targetManager.AddTargetsFromConfig(conf)
+
+	statusHandler := &web.StatusHandler{
+		BuildInfo:     BuildInfo,
+		Config:        &conf,
+		CurationState: curationState,
+		// Furnish the default status.
+		PrometheusStatus: &web.PrometheusStatus{},
+		TargetManager:    targetManager,
+	}
+
+	// The closing of curationState implicitly closes this routine.
+	go statusHandler.ServeRequestsForever()
+
+	metricsService := &api.MetricsService{
+		Config:        &conf,
+		TargetManager: targetManager,
+		Storage:       ts,
+	}
+
+	webService := &web.WebService{
+		StatusHandler:  statusHandler,
+		MetricsHandler: metricsService,
+	}
 
 	prometheus := prometheus{
-		storage:       *ts,
-		scrapeResults: scrapeResults,
+		curationState: curationState,
 		ruleResults:   ruleResults,
+		scrapeResults: scrapeResults,
+		storage:       *ts,
 	}
 	defer prometheus.close()
 
 	go ts.Serve()
 	go prometheus.interruptHandler()
 
-	// Queue depth will need to be exposed
-
-	targetManager := retrieval.NewTargetManager(scrapeResults, *concurrentRetrievalAllowance)
-	targetManager.AddTargetsFromConfig(conf)
-
 	ast.SetStorage(*ts)
 
 	ruleManager := rules.NewRuleManager(ruleResults, conf.EvaluationInterval())
@@ -116,16 +139,12 @@ func main() {
 		log.Fatalf("Error loading rule files: %v", err)
 	}
 
-	appState := &appstate.ApplicationState{
-		BuildInfo:     BuildInfo,
-		Config:        conf,
-		CurationState: make(chan metric.CurationState),
-		RuleManager:   ruleManager,
-		Storage:       *ts,
-		TargetManager: targetManager,
-	}
-
-	web.StartServing(appState)
+	go func() {
+		err := webService.ServeForever()
+		if err != nil {
+			log.Fatal(err)
+		}
+	}()
 
 	// TODO(all): Migrate this into prometheus.serve().
 	for {

model/Makefile

@@ -29,4 +29,4 @@ clean:
 	rm -rf generated/*
 	-rm -f $(MAKE_ARTIFACTS)
 
-.PHONY: generated
+.PHONY: clean generated

web/Makefile

@@ -11,13 +11,15 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-all: blob
+all: blob-stamp
 
-blob: static/generated/protocol_buffer.descriptor
+blob-stamp: static/generated/protocol_buffer.descriptor
 	$(MAKE) -C blob
+	touch $@
 
 clean:
 	$(MAKE) -C blob clean
+	-rm -f *-stamp
 
 static/generated:
 	mkdir -vp static/generated
@@ -25,4 +27,4 @@ static/generated:
 static/generated/protocol_buffer.descriptor: static/generated ../model/generated/descriptor.blob
 	cp -f ../model/generated/descriptor.blob $@
 
-.PHONY: blob clean
+.PHONY: clean

web/api/api.go

@@ -15,7 +15,9 @@ package api
 
 import (
 	"code.google.com/p/gorest"
-	"github.com/prometheus/prometheus/appstate"
+	"github.com/prometheus/prometheus/config"
+	"github.com/prometheus/prometheus/retrieval"
+	"github.com/prometheus/prometheus/storage/metric"
 	"github.com/prometheus/prometheus/utility"
 )
 
@@ -27,13 +29,9 @@ type MetricsService struct {
 	metrics    gorest.EndPoint `method:"GET" path:"/metrics" output:"string"`
 
 	setTargets gorest.EndPoint `method:"PUT" path:"/jobs/{jobName:string}/targets" postdata:"[]TargetGroup"`
+	time       utility.Time
 
-	appState *appstate.ApplicationState
-	time     utility.Time
-}
-
-func NewMetricsService(appState *appstate.ApplicationState) *MetricsService {
-	return &MetricsService{
-		appState: appState,
-	}
+	Config        *config.Config
+	TargetManager retrieval.TargetManager
+	Storage       *metric.TieredStorage
 }

web/api/query.go

@@ -96,7 +96,7 @@ func (serv MetricsService) QueryRange(expr string, end int64, duration int64, st
 }
 
 func (serv MetricsService) Metrics() string {
-	metricNames, err := serv.appState.Storage.GetAllValuesForLabel(model.MetricNameLabel)
+	metricNames, err := serv.Storage.GetAllValuesForLabel(model.MetricNameLabel)
 	rb := serv.ResponseBuilder()
 	serv.setAccessControlHeaders(rb)
 	rb.SetContentType(gorest.Application_Json)

web/api/targets.go

@@ -26,25 +26,31 @@ type TargetGroup struct {
 }
 
 func (serv MetricsService) SetTargets(targetGroups []TargetGroup, jobName string) {
-	if job := serv.appState.Config.GetJobByName(jobName); job == nil {
+	job := serv.Config.GetJobByName(jobName)
+	if job == nil {
 		rb := serv.ResponseBuilder()
 		rb.SetResponseCode(http.StatusNotFound)
-	} else {
-		newTargets := []retrieval.Target{}
-		for _, targetGroup := range targetGroups {
-			// Do mandatory map type conversion due to Go shortcomings.
-			baseLabels := model.LabelSet{
-				model.JobLabel: model.LabelValue(job.GetName()),
-			}
-			for label, value := range targetGroup.BaseLabels {
-				baseLabels[model.LabelName(label)] = model.LabelValue(value)
-			}
-
-			for _, endpoint := range targetGroup.Endpoints {
-				newTarget := retrieval.NewTarget(endpoint, time.Second*5, baseLabels)
-				newTargets = append(newTargets, newTarget)
-			}
+		return
+	}
+
+	newTargets := []retrieval.Target{}
+
+	for _, targetGroup := range targetGroups {
+		// Do mandatory map type conversion due to Go shortcomings.
+		baseLabels := model.LabelSet{
+			model.JobLabel: model.LabelValue(job.GetName()),
+		}
+		for label, value := range targetGroup.BaseLabels {
+			baseLabels[model.LabelName(label)] = model.LabelValue(value)
+		}
+
+		for _, endpoint := range targetGroup.Endpoints {
+			newTarget := retrieval.NewTarget(endpoint, time.Second*5, baseLabels)
+			newTargets = append(newTargets, newTarget)
 		}
-		serv.appState.TargetManager.ReplaceTargets(*job, newTargets, serv.appState.Config.ScrapeInterval())
 	}
+
+	// BUG(julius): Validate that this ScrapeInterval is in fact the proper one
+	// for the job.
+	serv.TargetManager.ReplaceTargets(*job, newTargets, serv.Config.ScrapeInterval())
 }

web/blob/.gitignore

@@ -1 +1,2 @@
-files.go
+files.go
+protocol_buffer.descriptor

web/status.go

@@ -15,27 +15,32 @@ package web
 
 import (
 	"flag"
-	"github.com/prometheus/prometheus/appstate"
+	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/retrieval"
 	"github.com/prometheus/prometheus/storage/metric"
 	"net/http"
+	"sync"
 )
 
 type PrometheusStatus struct {
+	BuildInfo   map[string]string
 	Config      string
+	Curation    metric.CurationState
+	Flags       map[string]string
 	Rules       string
 	TargetPools map[string]*retrieval.TargetPool
-	BuildInfo   map[string]string
-	Flags       map[string]string
-	Curation    metric.CurationState
 }
 
 type StatusHandler struct {
-	appState         *appstate.ApplicationState
+	BuildInfo        map[string]string
+	Config           *config.Config
+	CurationState    chan metric.CurationState
 	PrometheusStatus *PrometheusStatus
+	TargetManager    retrieval.TargetManager
+	mutex            sync.Mutex
 }
 
-func (h *StatusHandler) Run() {
+func (h *StatusHandler) ServeRequestsForever() {
 	flags := map[string]string{}
 
 	flag.VisitAll(func(f *flag.Flag) {
@@ -43,19 +48,22 @@ func (h *StatusHandler) Run() {
 	})
 
 	h.PrometheusStatus = &PrometheusStatus{
-		Config:      h.appState.Config.String(),
-		Rules:       "TODO: list rules here",
-		TargetPools: h.appState.TargetManager.Pools(),
-		BuildInfo:   h.appState.BuildInfo,
+		BuildInfo:   h.BuildInfo,
+		Config:      h.Config.String(),
 		Flags:       flags,
+		Rules:       "TODO: list rules here",
+		TargetPools: h.TargetManager.Pools(),
 	}
 
-	// Law of Demeter :-(
-	for state := range h.appState.CurationState {
+	for state := range h.CurationState {
+		h.Lock()
 		h.PrometheusStatus.Curation = state
+		h.Unlock()
 	}
 }
 
-func (h StatusHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+func (h *StatusHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	h.Lock()
+	defer h.Unlock()
 	executeTemplate(w, "status", h.PrometheusStatus)
 }

web/web.go

@@ -19,7 +19,6 @@ import (
 	"fmt"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/exp"
-	"github.com/prometheus/prometheus/appstate"
 	"github.com/prometheus/prometheus/web/api"
 	"github.com/prometheus/prometheus/web/blob"
 	"html/template"
@@ -34,8 +33,13 @@ var (
 	useLocalAssets = flag.Bool("useLocalAssets", false, "Read assets/templates from file instead of binary.")
 )
 
-func StartServing(appState *appstate.ApplicationState) {
-	gorest.RegisterService(api.NewMetricsService(appState))
+type WebService struct {
+	StatusHandler  *StatusHandler
+	MetricsHandler *api.MetricsService
+}
+
+func (w WebService) ServeForever() error {
+	gorest.RegisterService(w.MetricsHandler)
 
 	// TODO(julius): This will need to be rewritten once the exp package provides
 	// the coarse mux behaviors via a wrapper function.
@@ -44,10 +48,7 @@ func StartServing(appState *appstate.ApplicationState) {
 	exp.Handle("/debug/pprof/profile", http.HandlerFunc(pprof.Profile))
 	exp.Handle("/debug/pprof/symbol", http.HandlerFunc(pprof.Symbol))
 
-	statusHandler := &StatusHandler{appState: appState}
-	go statusHandler.Run()
-
-	exp.Handle("/", statusHandler)
+	exp.Handle("/", w.StatusHandler)
 	exp.HandleFunc("/graph", graphHandler)
 
 	exp.Handle("/api/", gorest.Handle())
@@ -59,7 +60,8 @@ func StartServing(appState *appstate.ApplicationState) {
 	}
 
 	log.Printf("listening on %s", *listenAddress)
-	go http.ListenAndServe(*listenAddress, exp.DefaultCoarseMux)
+
+	return http.ListenAndServe(*listenAddress, exp.DefaultCoarseMux)
 }
 
 func getTemplate(name string) (t *template.Template, err error) {