Implement paging and refactor stores to match new store interface with paging

storage/store/memory/util_test.go

@@ -0,0 +1,55 @@
+package memory
+
+import (
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage/store/paging"
+)
+
+func TestAddResult(t *testing.T) {
+	service := &core.Service{Name: "name", Group: "group"}
+	serviceStatus := core.NewServiceStatus(service.Key(), service.Group, service.Name)
+	for i := 0; i < core.MaximumNumberOfResults+10; i++ {
+		AddResult(serviceStatus, &core.Result{Timestamp: time.Now()})
+	}
+	if len(serviceStatus.Results) != core.MaximumNumberOfResults {
+		t.Errorf("expected serviceStatus.Results to not exceed a length of %d", core.MaximumNumberOfResults)
+	}
+}
+
+func TestShallowCopyServiceStatus(t *testing.T) {
+	service := &core.Service{Name: "name", Group: "group"}
+	serviceStatus := core.NewServiceStatus(service.Key(), service.Group, service.Name)
+	for i := 0; i < 25; i++ {
+		AddResult(serviceStatus, &core.Result{Timestamp: time.Now()})
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(1, 1)).Results) != 1 {
+		t.Errorf("expected to have 1 result")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(5, 0)).Results) != 0 {
+		t.Errorf("expected to have 0 results")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(-1, 20)).Results) != 0 {
+		t.Errorf("expected to have 0 result, because the page was invalid")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(1, -1)).Results) != 0 {
+		t.Errorf("expected to have 0 result, because the page size was invalid")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(1, 10)).Results) != 10 {
+		t.Errorf("expected to have 10 results, because given a page size of 10, page 1 should have 10 elements")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(2, 10)).Results) != 10 {
+		t.Errorf("expected to have 10 results, because given a page size of 10, page 2 should have 10 elements")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(3, 10)).Results) != 5 {
+		t.Errorf("expected to have 5 results, because given a page size of 10, page 3 should have 5 elements")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(4, 10)).Results) != 0 {
+		t.Errorf("expected to have 0 results, because given a page size of 10, page 4 should have 0 elements")
+	}
+	if len(ShallowCopyServiceStatus(serviceStatus, paging.NewServiceStatusParams().WithResults(1, 50)).Results) != 25 {
+		t.Errorf("expected to have 25 results, because there's only 25 results")
+	}
+}