galera-agent: log state data when responding "200 / unhealthy"

Previously galera-agent never logged data when a node was unhealthy. This made interrupt diagnosis of proxy flapping difficult. Now galera-agent outputs the parameters that determine the node to be unhealthy. [#187935541](https://www.pivotaltracker.com/story/show/187935541) Co-authored-by: Kim Bassett <kbassett@vmware.com> Co-authored-by: Kyle Ong <kyleo@vmware.com>
cloudfoundry · Jul 16, 2024 · a74baf5 · a74baf5
1 parent 618232f
commit a74baf5
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Showing 2 changed files with 30 additions and 3 deletions.
diff --git a/src/github.com/cloudfoundry-incubator/galera-healthcheck/api/api.go b/src/github.com/cloudfoundry-incubator/galera-healthcheck/api/api.go
@@ -141,12 +141,18 @@ func (r router) v1Status() http.Handler {
 
 		w.Header().Set("Content-Type", "application/json")
 
-		json.NewEncoder(w).Encode(V1StatusResponse{
+		healthy := s.IsHealthy(r.rootConfig.AvailableWhenReadOnly)
+		resp := V1StatusResponse{
 			WsrepLocalState:        uint(s.WsrepLocalState),
 			WsrepLocalStateComment: string(s.WsrepLocalState.Comment()),
 			WsrepLocalIndex:        s.WsrepLocalIndex,
-			Healthy:                s.IsHealthy(r.rootConfig.AvailableWhenReadOnly),
-		})
+			Healthy:                healthy,
+		}
+
+		if !healthy {
+			r.logger.Info(fmt.Sprintf("unhealthy state: %#v maintenanceEnabled: %t readOnly: %t", resp, s.MaintenanceEnabled, s.ReadOnly))
+		}
+		json.NewEncoder(w).Encode(resp)
 	})
 }
 

diff --git a/src/github.com/cloudfoundry-incubator/galera-healthcheck/api/api_test.go b/src/github.com/cloudfoundry-incubator/galera-healthcheck/api/api_test.go
@@ -291,6 +291,27 @@ var _ = Describe("Sidecar API", func() {
 					Expect(state.WsrepLocalStateComment).To(Equal(string(returnedState.WsrepLocalState.Comment())))
 					Expect(state.Healthy).To(BeTrue())
 				})
+
+				When("it interprets the state as 'unhealthy'", func() {
+					BeforeEach(func() {
+						stateSnapshotter.StateReturns(domain.DBState{
+							WsrepLocalIndex:    uint(0),
+							WsrepLocalState:    domain.WsrepLocalState(0),
+							ReadOnly:           false,
+							MaintenanceEnabled: true, // forces unhealthy state
+						}, nil)
+					})
+
+					It("logs the unhealthy state", func() {
+						req := createReq("api/v1/status", "GET")
+						_, err := http.DefaultClient.Do(req)
+						Expect(err).ToNot(HaveOccurred())
+
+						Expect(len(testLogger.Logs())).To(Equal(1))
+						logData := testLogger.Logs()[0]
+						Expect(logData.Message).To(Equal("mysql_cmd.unhealthy state: api.V1StatusResponse{WsrepLocalState:0x0, WsrepLocalStateComment:\"Initialized\", WsrepLocalIndex:0x0, Healthy:false} maintenanceEnabled: true readOnly: false"))
+					})
+				})
 			})
 
 			Context("when getting the state fails", func() {