health check endpoint for checking both the SQL store and also influx (#372)

This commit is contained in:
Michael Quigley 2023-08-08 13:48:34 -04:00
parent e4a1261e73
commit 7cc83e3e69
No known key found for this signature in database
GPG Key ID: 9B60314A9DD20A62
4 changed files with 75 additions and 3 deletions

View File

@ -128,6 +128,7 @@ func Run(inCfg *config.Config) error {
defer func() { _ = server.Shutdown() }()
server.Host = cfg.Endpoint.Host
server.Port = cfg.Endpoint.Port
rest_server_zrok.HealthCheck = HealthCheckHTTP
server.ConfigureAPI()
if err := server.Serve(); err != nil {
return errors.Wrap(err, "api server error")
@ -135,3 +136,7 @@ func Run(inCfg *config.Config) error {
return nil
}
func Store() *store.Store {
return str
}

62
controller/health.go Normal file
View File

@ -0,0 +1,62 @@
package controller
import (
"context"
"fmt"
"github.com/sirupsen/logrus"
"net/http"
)
func HealthCheckHTTP(w http.ResponseWriter, _ *http.Request) {
if err := healthCheckStore(w); err != nil {
logrus.Error(err)
return
}
if err := healthCheckMetrics(w); err != nil {
logrus.Error(err)
return
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
w.Write([]byte("<html><body><h1>Healthy</h1></body></html>"))
}
func healthCheckStore(w http.ResponseWriter) error {
trx, err := str.Begin()
if err != nil {
http.Error(w, "error starting transaction", http.StatusInternalServerError)
return err
}
defer func() {
_ = trx.Rollback()
}()
count := -1
if err := trx.QueryRowx("select count(0) from migrations").Scan(&count); err != nil {
http.Error(w, "error selecting migration count", http.StatusInternalServerError)
return err
}
logrus.Debugf("%d migrations", count)
return nil
}
func healthCheckMetrics(w http.ResponseWriter) error {
if cfg.Metrics != nil && cfg.Metrics.Influx != nil {
queryApi := idb.QueryAPI(cfg.Metrics.Influx.Org)
query := fmt.Sprintf("from(bucket: \"%v\")\n", cfg.Metrics.Influx.Bucket) +
fmt.Sprintf("|> range(start: -5s)\n") +
"|> filter(fn: (r) => r[\"_measurement\"] == \"xfer\")\n" +
"|> filter(fn: (r) => r[\"_field\"] == \"rx\" or r[\"_field\"] == \"tx\")\n" +
"|> filter(fn: (r) => r[\"namespace\"] == \"backend\")\n" +
"|> sum()"
result, err := queryApi.Query(context.Background(), query)
if err != nil {
http.Error(w, "error querying influx", http.StatusInternalServerError)
return err
}
results := 0
for result.Next() {
results++
}
logrus.Debugf("%d results", results)
}
return nil
}

View File

@ -13,6 +13,8 @@ import (
"github.com/openziti/zrok/rest_server_zrok/operations"
)
var HealthCheck func(w http.ResponseWriter, r *http.Request)
//go:generate swagger generate server --target ../../zrok --name Zrok --spec ../specs/zrok.yml --model-package rest_model_zrok --server-package rest_server_zrok --principal interface{} --exclude-main
func configureFlags(api *operations.ZrokAPI) {
@ -53,6 +55,5 @@ func setupMiddlewares(handler http.Handler) http.Handler {
// The middleware configuration happens before anything, this middleware also applies to serving the swagger.json document.
// So this is a good place to plug in a panic handling middleware, logging and metrics.
func setupGlobalMiddleware(handler http.Handler) http.Handler {
logrus.Infof("configuring")
return ui.StaticBuilder(handler)
return ui.Middleware(handler, HealthCheck)
}

View File

@ -9,7 +9,7 @@ import (
"strings"
)
func StaticBuilder(handler http.Handler) http.Handler {
func Middleware(handler http.Handler, healthCheck func(w http.ResponseWriter, r *http.Request)) http.Handler {
logrus.Infof("building")
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if strings.HasPrefix(r.URL.Path, "/api/v1") {
@ -17,6 +17,10 @@ func StaticBuilder(handler http.Handler) http.Handler {
handler.ServeHTTP(w, r)
return
}
if strings.HasPrefix(r.URL.Path, "/health") {
healthCheck(w, r)
return
}
logrus.Debugf("directing '%v' to static handler", r.URL.Path)