feat: add optional /logs?module= filter param

This allows to uniquely identify a probe by target and module.
Previously the target= selector was not necessarily unique, when multiple modules had probed a target.

main.go

@@ -232,9 +232,14 @@ func run() int {
 			http.Error(w, "Probe id or target must be defined as http query parameters", http.StatusBadRequest)
 			return
 		}
+		module := r.URL.Query().Get("module")
+		if target == "" && module != "" {
+			http.Error(w, "Probe module filter only works in conjunction with target paramer", http.StatusBadRequest)
+			return
+		}
 		result := new(prober.Result)
 		if target != "" {
-			result = rh.GetByTarget(target)
+			result = rh.GetByTarget(target, module)
 			if result == nil {
 				http.Error(w, "Probe target not found", http.StatusNotFound)
 				return

prober/history.go

@@ -97,18 +97,20 @@ func (rh *ResultHistory) GetById(id int64) *Result {
 	return nil
 }
 
-// Get returns a given result by url.
-func (rh *ResultHistory) GetByTarget(target string) *Result {
+// Get returns a given result by url, optionally filtered by a module name.
+func (rh *ResultHistory) GetByTarget(target string, module string) *Result {
 	rh.mu.Lock()
 	defer rh.mu.Unlock()
 
 	for _, r := range rh.preservedFailedResults {
-		if r.Target == target {
+		if module == "" && r.Target == target ||
+			r.ModuleName == module && r.Target == target {
 			return r
 		}
 	}
 	for _, r := range rh.results {
-		if r.Target == target {
+		if module == "" && r.Target == target ||
+			r.ModuleName == module && r.Target == target {
 			return r
 		}
 	}

prober/history_test.go

@@ -112,13 +112,14 @@ func TestHistoryGetById(t *testing.T) {
 }
 
 func TestHistoryGetByTarget(t *testing.T) {
-	history := &ResultHistory{MaxResults: 2}
+	history := &ResultHistory{MaxResults: 3}
 
-	history.Add("module", "target-0", fmt.Sprintf("result %d", history.nextId), true)
-	history.Add("module", "target-1", fmt.Sprintf("result %d", history.nextId), false)
+	history.Add("module-0", "target-0", fmt.Sprintf("result %d", history.nextId), true)
+	history.Add("module-1", "target-1", fmt.Sprintf("result %d", history.nextId), false)
+	history.Add("module-0", "target-1", fmt.Sprintf("result %d", history.nextId), false)
 
 	// Get a Result object for a target that exists
-	resultTrue := history.GetByTarget("target-0")
+	resultTrue := history.GetByTarget("target-0", "")
 	if resultTrue == nil {
 		t.Errorf("Error finding the result in history by target for target-0")
 	} else {
@@ -127,17 +128,38 @@ func TestHistoryGetByTarget(t *testing.T) {
 		}
 	}
 
-	resultFalse := history.GetByTarget("target-1")
+	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)
 		}
+		if resultFalse.ModuleName != "module-1" {
+			t.Errorf("Error finding the result in history by target for target: expected \"%s\" and got \"%s\"", "module-1", resultFalse.ModuleName)
+		}
 	}
 
 	// Get a Result object for a target that doesn't exist
-	if history.GetByTarget("target-5") != nil {
+	if history.GetByTarget("target-5", "") != nil {
 		t.Errorf("Error finding the result in history by target for target-5")
 	}
+
+	// Get a result by existing target and non-matching module
+	if history.GetByTarget("target-1", "module-5") != nil {
+		t.Errorf("Incorrectly found a result in history by target for [target-1,module-5]")
+	}
+
+	// Get a result by existing target and matching module
+	if result := history.GetByTarget("target-1", "module-1"); result == nil {
+		t.Errorf("Incorrectly found no result in history by target for [target-1,module-1]")
+	} else {
+		if result.Target != "target-1" {
+			t.Errorf("Error finding the result in history by target and module for target: expected \"%s\" and got \"%s\"", "target-1", result.Target)
+		}
+		if result.ModuleName != "module-1" {
+			t.Errorf("Error finding the result in history by target and module for target: expected \"%s\" and got \"%s\"", "module-1", result.ModuleName)
+		}
+	}
 }
+