From b0a9fe6d718947863058d2a3acb884cabd831381 Mon Sep 17 00:00:00 2001
From: Rasmus Dahlberg <rasmus@rgdd.se>
Date: Sat, 25 Mar 2023 15:26:33 +0100
Subject: Improve health and metrics

---
 internal/options/options.go |   4 ++
 main.go                     | 105 +++++++++++++++++++++++++++++++-------------
 2 files changed, 78 insertions(+), 31 deletions(-)

diff --git a/internal/options/options.go b/internal/options/options.go
index c988713..a567b0e 100644
--- a/internal/options/options.go
+++ b/internal/options/options.go
@@ -17,6 +17,8 @@ type Options struct {
 	MaxResponse int64
 
 	// Health and metrics
+	CheckerDomain   string
+	CheckerInterval time.Duration
 	MetricsInterval time.Duration
 }
 
@@ -29,6 +31,8 @@ func Parse() (opts Options) {
 	flag.DurationVar(&opts.Timeout, "t", 10*time.Second, "timeout for each website visit")
 	flag.Int64Var(&opts.MaxResponse, "r", 128, "max response body size to accept in MiB")
 
+	flag.StringVar(&opts.CheckerDomain, "c", "rgdd.se", "domain with onion location for setup santity-checks")
+	flag.DurationVar(&opts.CheckerInterval, "C", 10*time.Second, "how often to to run checker")
 	flag.DurationVar(&opts.MetricsInterval, "m", 5*time.Second, "how often to emit metrics")
 
 	flag.Parse()
diff --git a/main.go b/main.go
index f04ea17..146a62e 100644
--- a/main.go
+++ b/main.go
@@ -62,6 +62,15 @@ func main() {
 		await(ctx, cancel)
 	}()
 
+	if opts.CheckerDomain != "" {
+		log.Printf("INFO: starting checker\n")
+		go func() {
+			wg.Add(1)
+			defer wg.Done()
+			checker(ctx, cancel, &opts, cli)
+		}()
+	}
+
 	log.Printf("INFO: starting %d workers\n", opts.NumWorkers)
 	for i := 0; i < opts.NumWorkers; i++ {
 		go func() {
@@ -101,42 +110,65 @@ func await(ctx context.Context, cancel context.CancelFunc) {
 	cancel()
 }
 
+func checker(ctx context.Context, cancel context.CancelFunc, opts *options.Options, cli *http.Client) {
+	question := qna.Question{opts.CheckerDomain}
+	answerCh := make(chan qna.Answer, 1)
+	defer close(answerCh)
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(opts.CheckerInterval):
+			work(ctx, opts, cli, question, answerCh)
+			answer := <-answerCh
+			if answer.HTTP == "" && answer.HTML == "" {
+				log.Printf("ERROR: checker expected onion for %+v", answer)
+				cancel()
+				return
+			}
+		}
+	}
+}
+
 func workHandler(ctx context.Context, opts options.Options, cli *http.Client, questionCh chan qna.Question, answerCh chan qna.Answer) {
 	for {
 		select {
 		case <-ctx.Done():
 			return
 		case question := <-questionCh:
-			func() {
-				cctx, cancel := context.WithTimeout(ctx, opts.Timeout)
-				defer cancel()
+			work(ctx, &opts, cli, question, answerCh)
+		}
+	}
+}
 
-				req, err := http.NewRequestWithContext(cctx, http.MethodGet, "https://"+question.Domain, nil)
-				if err != nil {
-					return
-				}
+func work(ctx context.Context, opts *options.Options, cli *http.Client, question qna.Question, answerCh chan qna.Answer) {
+	cctx, cancel := context.WithTimeout(ctx, opts.Timeout)
+	defer cancel()
 
-				answer := qna.Answer{Domain: question.Domain}
-				rsp, err := cli.Do(req)
-				if err != nil {
-					answerCh <- answer
-					return
-				}
-				defer rsp.Body.Close()
-				answer.OK = true
+	req, err := http.NewRequestWithContext(cctx, http.MethodGet, "https://"+question.Domain, nil)
+	if err != nil {
+		return
+	}
 
-				onion, ok := onionloc.HTTP(rsp)
-				if ok {
-					answer.HTTP = onion
-				}
-				onion, ok = onionloc.HTML(rsp)
-				if ok {
-					answer.HTML = onion
-				}
-				answerCh <- answer
-			}()
-		}
+	answer := qna.Answer{Domain: question.Domain}
+	rsp, err := cli.Do(req)
+	if err != nil {
+		answerCh <- answer
+		return
 	}
+	defer rsp.Body.Close()
+	answer.OK = true
+
+	onion, ok := onionloc.HTTP(rsp)
+	if ok {
+		answer.HTTP = onion
+	}
+	onion, ok = onionloc.HTML(rsp)
+	if ok {
+		answer.HTML = onion
+	}
+	answerCh <- answer
 }
 
 func workAggregator(ctx context.Context, opts options.Options, answerCh chan qna.Answer) {
@@ -144,7 +176,7 @@ func workAggregator(ctx context.Context, opts options.Options, answerCh chan qna
 	numOnions := 0
 	numAll := 0
 	output := func() {
-		log.Printf("INFO: %d/%d connected, %d sites configured Onion-Location\n", numConnect, numAll, numOnions)
+		log.Printf("SUMMARY: %d/%d connected, %d sites configured Onion-Location\n", numConnect, numAll, numOnions)
 	}
 
 	handleAnswer := func(a qna.Answer) {
@@ -160,8 +192,6 @@ func workAggregator(ctx context.Context, opts options.Options, answerCh chan qna
 		}
 	}
 
-	ticker := time.NewTicker(opts.MetricsInterval)
-	defer ticker.Stop()
 	defer output()
 	for {
 		select {
@@ -177,8 +207,6 @@ func workAggregator(ctx context.Context, opts options.Options, answerCh chan qna
 			}
 		case a := <-answerCh:
 			handleAnswer(a)
-		case <-ticker.C:
-			output()
 		}
 	}
 }
@@ -203,10 +231,25 @@ func workGenerator(ctx context.Context, opts options.Options, fp *os.File, quest
 		nextLine++
 	}
 
+	ticker := time.NewTicker(opts.MetricsInterval)
+	defer ticker.Stop()
+
+	startTime := time.Now().Unix()
+	latestTime := startTime
+	latestCount := opts.NextLine
 	for scanner.Scan() {
 		select {
 		case <-ctx.Done():
 			return nextLine, false
+		case <-ticker.C:
+			now := time.Now().Unix()
+			log.Printf("INFO: currently %.1f sites/s, %.1f sites/s since start\n",
+				float64(nextLine-opts.NextLine)/float64(now-startTime),
+				float64(nextLine-latestCount)/float64(now-latestTime),
+			)
+
+			latestCount = nextLine
+			latestTime = now
 		case questionCh <- qna.Question{Domain: scanner.Text()}:
 			nextLine++
 		}
-- 
cgit v1.2.3