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-rw-r--r--kube2msb/src/vendor/github.com/coreos/pkg/health/health.go127
1 files changed, 127 insertions, 0 deletions
diff --git a/kube2msb/src/vendor/github.com/coreos/pkg/health/health.go b/kube2msb/src/vendor/github.com/coreos/pkg/health/health.go
new file mode 100644
index 0000000..a1c3610
--- /dev/null
+++ b/kube2msb/src/vendor/github.com/coreos/pkg/health/health.go
@@ -0,0 +1,127 @@
+package health
+
+import (
+ "expvar"
+ "fmt"
+ "log"
+ "net/http"
+
+ "github.com/coreos/pkg/httputil"
+)
+
+// Checkables should return nil when the thing they are checking is healthy, and an error otherwise.
+type Checkable interface {
+ Healthy() error
+}
+
+// Checker provides a way to make an endpoint which can be probed for system health.
+type Checker struct {
+ // Checks are the Checkables to be checked when probing.
+ Checks []Checkable
+
+ // Unhealthyhandler is called when one or more of the checks are unhealthy.
+ // If not provided DefaultUnhealthyHandler is called.
+ UnhealthyHandler UnhealthyHandler
+
+ // HealthyHandler is called when all checks are healthy.
+ // If not provided, DefaultHealthyHandler is called.
+ HealthyHandler http.HandlerFunc
+}
+
+func (c Checker) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+ unhealthyHandler := c.UnhealthyHandler
+ if unhealthyHandler == nil {
+ unhealthyHandler = DefaultUnhealthyHandler
+ }
+
+ successHandler := c.HealthyHandler
+ if successHandler == nil {
+ successHandler = DefaultHealthyHandler
+ }
+
+ if r.Method != "GET" {
+ w.Header().Set("Allow", "GET")
+ w.WriteHeader(http.StatusMethodNotAllowed)
+ return
+ }
+
+ if err := Check(c.Checks); err != nil {
+ unhealthyHandler(w, r, err)
+ return
+ }
+
+ successHandler(w, r)
+}
+
+type UnhealthyHandler func(w http.ResponseWriter, r *http.Request, err error)
+
+type StatusResponse struct {
+ Status string `json:"status"`
+ Details *StatusResponseDetails `json:"details,omitempty"`
+}
+
+type StatusResponseDetails struct {
+ Code int `json:"code,omitempty"`
+ Message string `json:"message,omitempty"`
+}
+
+func Check(checks []Checkable) (err error) {
+ errs := []error{}
+ for _, c := range checks {
+ if e := c.Healthy(); e != nil {
+ errs = append(errs, e)
+ }
+ }
+
+ switch len(errs) {
+ case 0:
+ err = nil
+ case 1:
+ err = errs[0]
+ default:
+ err = fmt.Errorf("multiple health check failure: %v", errs)
+ }
+
+ return
+}
+
+func DefaultHealthyHandler(w http.ResponseWriter, r *http.Request) {
+ err := httputil.WriteJSONResponse(w, http.StatusOK, StatusResponse{
+ Status: "ok",
+ })
+ if err != nil {
+ // TODO(bobbyrullo): replace with logging from new logging pkg,
+ // once it lands.
+ log.Printf("Failed to write JSON response: %v", err)
+ }
+}
+
+func DefaultUnhealthyHandler(w http.ResponseWriter, r *http.Request, err error) {
+ writeErr := httputil.WriteJSONResponse(w, http.StatusInternalServerError, StatusResponse{
+ Status: "error",
+ Details: &StatusResponseDetails{
+ Code: http.StatusInternalServerError,
+ Message: err.Error(),
+ },
+ })
+ if writeErr != nil {
+ // TODO(bobbyrullo): replace with logging from new logging pkg,
+ // once it lands.
+ log.Printf("Failed to write JSON response: %v", err)
+ }
+}
+
+// ExpvarHandler is copied from https://golang.org/src/expvar/expvar.go, where it's sadly unexported.
+func ExpvarHandler(w http.ResponseWriter, r *http.Request) {
+ w.Header().Set("Content-Type", "application/json; charset=utf-8")
+ fmt.Fprintf(w, "{\n")
+ first := true
+ expvar.Do(func(kv expvar.KeyValue) {
+ if !first {
+ fmt.Fprintf(w, ",\n")
+ }
+ first = false
+ fmt.Fprintf(w, "%q: %s", kv.Key, kv.Value)
+ })
+ fmt.Fprintf(w, "\n}\n")
+}