feat: Allow to get Probe logs by target

main.go

@@ -212,14 +212,32 @@ func run() int {
 	http.HandleFunc(path.Join(*routePrefix, "/logs"), func(w http.ResponseWriter, r *http.Request) {
 		id, err := strconv.ParseInt(r.URL.Query().Get("id"), 10, 64)
 		if err != nil {
-			http.Error(w, "Invalid probe id", 500)
+			id = -1
+		}
+		target := r.URL.Query().Get("target")
+		if err == nil && target != "" {
+			http.Error(w, "Probe id and target can't be defined at the same time", http.StatusBadRequest)
 			return
 		}
-		result := rh.Get(id)
-		if result == nil {
-			http.Error(w, "Probe id not found", 404)
+		if id == -1 && target == "" {
+			http.Error(w, "Probe id or target must be defined as http query parameters", http.StatusBadRequest)
 			return
 		}
+		result := new(prober.Result)
+		if target != "" {
+			result = rh.GetByTarget(target)
+			if result == nil {
+				http.Error(w, "Probe target not found", http.StatusNotFound)
+				return
+			}
+		} else {
+			result = rh.GetById(id)
+			if result == nil {
+				http.Error(w, "Probe id not found", http.StatusNotFound)
+				return
+			}
+		}
+
 		w.Header().Set("Content-Type", "text/plain")
 		w.Write([]byte(result.DebugOutput))
 	})
@@ -230,7 +248,7 @@ func run() int {
 		sc.RUnlock()
 		if err != nil {
 			level.Warn(logger).Log("msg", "Error marshalling configuration", "err", err)
-			http.Error(w, err.Error(), 500)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 		w.Header().Set("Content-Type", "text/plain")

prober/history.go

@@ -78,8 +78,8 @@ func (rh *ResultHistory) List() []*Result {
 	return append(rh.preservedFailedResults[:], rh.results...)
 }
 
-// Get returns a given result.
-func (rh *ResultHistory) Get(id int64) *Result {
+// Get returns a given result by id.
+func (rh *ResultHistory) GetById(id int64) *Result {
 	rh.mu.Lock()
 	defer rh.mu.Unlock()
 
@@ -96,3 +96,22 @@ func (rh *ResultHistory) Get(id int64) *Result {
 
 	return nil
 }
+
+// Get returns a given result by url.
+func (rh *ResultHistory) GetByTarget(target string) *Result {
+	rh.mu.Lock()
+	defer rh.mu.Unlock()
+
+	for _, r := range rh.preservedFailedResults {
+		if r.Target == target {
+			return r
+		}
+	}
+	for _, r := range rh.results {
+		if r.Target == target {
+			return r
+		}
+	}
+
+	return nil
+}

prober/history_test.go

@@ -79,3 +79,65 @@ func TestHistoryPreservesExpiredFailedResults(t *testing.T) {
 		}
 	}
 }
+
+func TestHistoryGetById(t *testing.T) {
+	history := &ResultHistory{MaxResults: 2}
+
+	history.Add("module", "target-0", fmt.Sprintf("result %d", history.nextId), true)
+	history.Add("module", "target-1", fmt.Sprintf("result %d", history.nextId), false)
+
+	// Get a Result object for a target that exists
+	resultTrue := history.GetById(0)
+	if resultTrue == nil {
+		t.Errorf("Error finding the result in history by id for id: 1")
+	} else {
+		if resultTrue.Id != 0 {
+			t.Errorf("Error finding the result in history by id: expected \"%d\" and got \"%d\"", 0, resultTrue.Id)
+		}
+	}
+
+	resultFalse := history.GetById(1)
+	if resultFalse == nil {
+		t.Errorf("Error finding the result in history by id for id: 1")
+	} else {
+		if resultFalse.Id != 1 {
+			t.Errorf("Error finding the result in history by id: expected \"%d\" and got \"%d\"", 1, resultFalse.Id)
+		}
+	}
+
+	// Get a Result object for a target that doesn't exist
+	if history.GetById(5) != nil {
+		t.Errorf("Error finding the result in history by id for id: 5")
+	}
+}
+
+func TestHistoryGetByTarget(t *testing.T) {
+	history := &ResultHistory{MaxResults: 2}
+
+	history.Add("module", "target-0", fmt.Sprintf("result %d", history.nextId), true)
+	history.Add("module", "target-1", fmt.Sprintf("result %d", history.nextId), false)
+
+	// Get a Result object for a target that exists
+	resultTrue := history.GetByTarget("target-0")
+	if resultTrue == nil {
+		t.Errorf("Error finding the result in history by target for target-0")
+	} else {
+		if resultTrue.Target != "target-0" {
+			t.Errorf("Error finding the result in history by target for target: expected \"%s\" and got \"%s\"", "target-0", resultTrue.Target)
+		}
+	}
+
+	resultFalse := history.GetByTarget("target-1")
+	if resultFalse == nil {
+		t.Errorf("Error finding the result in history by target for target-1")
+	} else {
+		if resultFalse.Target != "target-1" {
+			t.Errorf("Error finding the result in history by target for target: expected \"%s\" and got \"%s\"", "target-1", resultFalse.Target)
+		}
+	}
+
+	// Get a Result object for a target that doesn't exist
+	if history.GetByTarget("target-5") != nil {
+		t.Errorf("Error finding the result in history by target for target-5")
+	}
+}