18947: Handle health and metrics requests in lib/service.

[arvados.git] / lib / service / cmd.go

diff --git a/lib/service/cmd.go b/lib/service/cmd.go
index 1ed2ac1314c3618014269450cbc8e78921988657..b7decd88a4bbc5a6cfad8d9373bd5894105a37af 100644 (file)
--- a/lib/service/cmd.go
+++ b/lib/service/cmd.go
@@ -20,10 +20,14 @@ import (
        "git.arvados.org/arvados.git/lib/cmd"
        "git.arvados.org/arvados.git/lib/config"
        "git.arvados.org/arvados.git/sdk/go/arvados"
+       "git.arvados.org/arvados.git/sdk/go/auth"
        "git.arvados.org/arvados.git/sdk/go/ctxlog"
+       "git.arvados.org/arvados.git/sdk/go/health"
        "git.arvados.org/arvados.git/sdk/go/httpserver"
        "github.com/coreos/go-systemd/daemon"
+       "github.com/julienschmidt/httprouter"
        "github.com/prometheus/client_golang/prometheus"
+       "github.com/prometheus/client_golang/prometheus/promhttp"
        "github.com/sirupsen/logrus"
 )
 
@@ -126,7 +130,9 @@ func (c *command) RunCommand(prog string, args []string, stdin io.Reader, stdout
                httpserver.HandlerWithDeadline(cluster.API.RequestTimeout.Duration(),
                        httpserver.AddRequestIDs(
                                httpserver.LogRequests(
-                                       httpserver.NewRequestLimiter(cluster.API.MaxConcurrentRequests, handler, reg)))))
+                                       interceptHealthReqs(cluster.ManagementToken, handler.CheckHealth,
+                                               interceptMetricsReqs(cluster.ManagementToken, reg, log,
+                                                       httpserver.NewRequestLimiter(cluster.API.MaxConcurrentRequests, handler, reg)))))))
        srv := &httpserver.Server{
                Server: http.Server{
                        Handler:     instrumented.ServeAPI(cluster.ManagementToken, instrumented),
@@ -172,6 +178,29 @@ func (c *command) RunCommand(prog string, args []string, stdin io.Reader, stdout
        return 0
 }
 
+func interceptHealthReqs(mgtToken string, checkHealth func() error, next http.Handler) http.Handler {
+       mux := httprouter.New()
+       mux.Handler("GET", "/_health/ping", &health.Handler{
+               Token:  mgtToken,
+               Prefix: "/_health/",
+               Routes: health.Routes{"ping": checkHealth},
+       })
+       mux.NotFound = next
+       return mux
+}
+
+func interceptMetricsReqs(mgtToken string, reg *prometheus.Registry, log logrus.FieldLogger, next http.Handler) http.Handler {
+       mux := httprouter.New()
+       metricsH := auth.RequireLiteralToken(mgtToken,
+               promhttp.HandlerFor(reg, promhttp.HandlerOpts{
+                       ErrorLog: log,
+               }))
+       mux.Handler("GET", "/metrics", metricsH)
+       mux.Handler("GET", "/metrics.json", metricsH)
+       mux.NotFound = next
+       return mux
+}
+
 func getListenAddr(svcs arvados.Services, prog arvados.ServiceName, log logrus.FieldLogger) (arvados.URL, error) {
        svc, ok := svcs.Map()[prog]
        if !ok {