cmd/prober: add check endpoint for scripting
When the prober's /check endpoint is hit, it will run all probes send
a non-200 status code if any failed. It also writes the failed probes
in text format.
Intended for scripting.
Change-Id: I4dd2c962bb09f56051f235f2f33ac12a82e5aefa
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/277172
Trust: Jonathan Amsterdam <jba@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jamal Carvalho <jamal@golang.org>
diff --git a/cmd/prober/main.go b/cmd/prober/main.go
index 3c32602..1929372 100644
--- a/cmd/prober/main.go
+++ b/cmd/prober/main.go
@@ -222,8 +222,10 @@
cfg.Dump(os.Stderr)
log.SetLevel(cfg.LogLevel)
- if _, err := log.UseStackdriver(ctx, cfg, "prober-log"); err != nil {
- log.Fatal(ctx, err)
+ if cfg.OnGCP() {
+ if _, err := log.UseStackdriver(ctx, cfg, "prober-log"); err != nil {
+ log.Fatal(ctx, err)
+ }
}
var jsonCreds []byte
@@ -256,6 +258,7 @@
http.ServeFile(w, r, "content/static/img/favicon.ico")
})
http.HandleFunc("/", handleProbe)
+ http.HandleFunc("/check", handleCheck)
addr := cfg.HostAddr("localhost:8080")
log.Infof(ctx, "Listening on addr %s", addr)
@@ -265,10 +268,12 @@
// ProbeStatus records the result if a single probe attempt
type ProbeStatus struct {
Probe *Probe
+ Code int // status code of response
Text string // describes what happened: "OK", or "FAILED" with a reason
Latency int // in milliseconds
}
+// handleProbe runs probes and displays their results. It always returns a 200.
func handleProbe(w http.ResponseWriter, r *http.Request) {
statuses := runProbes(r.Context())
var data = struct {
@@ -289,6 +294,28 @@
}
}
+// handleCheck runs probes, and returns a 200 only if they all succeed.
+// Otherwise it returns the status code of the first failing response.
+func handleCheck(w http.ResponseWriter, r *http.Request) {
+ statuses := runProbes(r.Context())
+ var bads []*ProbeStatus
+ for _, s := range statuses {
+ if s.Code != http.StatusOK {
+ bads = append(bads, s)
+ }
+ }
+ w.Header().Set("Content-Type", "text/plain")
+ if len(bads) == 0 {
+ fmt.Fprintf(w, "All probes succeeded.\n")
+ } else {
+ w.WriteHeader(bads[0].Code)
+ fmt.Fprintf(w, "SOME PROBES FAILED:\n")
+ for _, b := range bads {
+ fmt.Fprintf(w, "%3d /%s\n", b.Code, b.Probe.RelativeURL)
+ }
+ }
+}
+
func runProbes(ctx context.Context) []*ProbeStatus {
var statuses []*ProbeStatus
for _, p := range probes {
@@ -302,7 +329,10 @@
}
func runProbe(ctx context.Context, p *Probe) *ProbeStatus {
- status := &ProbeStatus{Probe: p}
+ status := &ProbeStatus{
+ Probe: p,
+ Code: 499, // not a real code; means request never sent
+ }
url := baseURL + "/" + p.RelativeURL
log.Infof(ctx, "running %s = %s", p.Name, url)
defer func() {
@@ -337,6 +367,7 @@
return status
}
defer res.Body.Close()
+ status.Code = res.StatusCode
if res.StatusCode != http.StatusOK {
status.Text = fmt.Sprintf("FAILED with status %s", res.Status)
record(res.Status)
