feat: Set minimum interval for endpoints with [DOMAIN_EXPIRATION] to 5m

README.md

@@ -1356,8 +1356,8 @@ endpoints:
 
 **NOTE**: The usage of the `[DOMAIN_EXPIRATION]` placeholder requires Gatus to send a request to the official IANA WHOIS service [through a library](https://github.com/TwiN/whois)
 and in some cases, a secondary request to a TLD-specific WHOIS server (e.g. `whois.nic.sh`). 
-You are also responsible for sending requests at a reasonable rate, as the WHOIS service may throttle your IP address if you send too many requests.
-The duration taken by the WHOIS request(s) is excluded from the request's response time.
+To prevent the WHOIS service from throttling your IP address if you send too many requests, Gatus will prevent you from
+using the `[DOMAIN_EXPIRATION]` placeholder on an endpoint with an interval of less than `5m`.
 
 
 ### disable-monitoring-lock

core/endpoint.go

@@ -58,6 +58,12 @@ var (
 
 	// ErrUnknownEndpointType is the error with which Gatus will panic if an endpoint has an unknown type
 	ErrUnknownEndpointType = errors.New("unknown endpoint type")
+
+	// ErrInvalidEndpointIntervalForDomainExpirationPlaceholder is the error with which Gatus will panic if an endpoint
+	// has both an interval smaller than 5 minutes and a condition with DomainExpirationPlaceholder.
+	// This is because the free whois service we are using should not be abused, especially considering the fact that
+	// the data takes a while to be updated.
+	ErrInvalidEndpointIntervalForDomainExpirationPlaceholder = errors.New("the minimum interval for an endpoint with a condition using the " + DomainExpirationPlaceholder + " placeholder is 300s (5m)")
 )
 
 // Endpoint is the configuration of a monitored
@@ -191,6 +197,13 @@ func (endpoint *Endpoint) ValidateAndSetDefaults() error {
 	if len(endpoint.Conditions) == 0 {
 		return ErrEndpointWithNoCondition
 	}
+	if endpoint.Interval < 5*time.Minute {
+		for _, condition := range endpoint.Conditions {
+			if condition.hasDomainExpirationPlaceholder() {
+				return ErrInvalidEndpointIntervalForDomainExpirationPlaceholder
+			}
+		}
+	}
 	if endpoint.DNS != nil {
 		return endpoint.DNS.validateAndSetDefault()
 	}

core/endpoint_test.go

@@ -372,11 +372,10 @@ func TestEndpoint_ValidateAndSetDefaults(t *testing.T) {
 }
 
 func TestEndpoint_ValidateAndSetDefaultsWithClientConfig(t *testing.T) {
-	condition := Condition("[STATUS] == 200")
 	endpoint := Endpoint{
 		Name:       "website-health",
 		URL:        "https://twin.sh/health",
-		Conditions: []Condition{condition},
+		Conditions: []Condition{Condition("[STATUS] == 200")},
 		ClientConfig: &client.Config{
 			Insecure:       true,
 			IgnoreRedirect: true,
@@ -399,51 +398,10 @@ func TestEndpoint_ValidateAndSetDefaultsWithClientConfig(t *testing.T) {
 	}
 }
 
-func TestEndpoint_ValidateAndSetDefaultsWithNoName(t *testing.T) {
-	defer func() { recover() }()
-	condition := Condition("[STATUS] == 200")
-	endpoint := &Endpoint{
-		Name:       "",
-		URL:        "http://example.com",
-		Conditions: []Condition{condition},
-	}
-	err := endpoint.ValidateAndSetDefaults()
-	if err == nil {
-		t.Fatal("Should've returned an error because endpoint didn't have a name, which is a mandatory field")
-	}
-}
-
-func TestEndpoint_ValidateAndSetDefaultsWithNoUrl(t *testing.T) {
-	defer func() { recover() }()
-	condition := Condition("[STATUS] == 200")
-	endpoint := &Endpoint{
-		Name:       "example",
-		URL:        "",
-		Conditions: []Condition{condition},
-	}
-	err := endpoint.ValidateAndSetDefaults()
-	if err == nil {
-		t.Fatal("Should've returned an error because endpoint didn't have an url, which is a mandatory field")
-	}
-}
-
-func TestEndpoint_ValidateAndSetDefaultsWithNoConditions(t *testing.T) {
-	defer func() { recover() }()
-	endpoint := &Endpoint{
-		Name:       "example",
-		URL:        "http://example.com",
-		Conditions: nil,
-	}
-	err := endpoint.ValidateAndSetDefaults()
-	if err == nil {
-		t.Fatal("Should've returned an error because endpoint didn't have at least 1 condition")
-	}
-}
-
 func TestEndpoint_ValidateAndSetDefaultsWithDNS(t *testing.T) {
 	endpoint := &Endpoint{
 		Name: "dns-test",
-		URL:  "http://example.com",
+		URL:  "https://example.com",
 		DNS: &DNS{
 			QueryType: "A",
 			QueryName: "example.com",
@@ -452,13 +410,70 @@ func TestEndpoint_ValidateAndSetDefaultsWithDNS(t *testing.T) {
 	}
 	err := endpoint.ValidateAndSetDefaults()
 	if err != nil {
-
+		t.Error("did not expect an error, got", err)
 	}
 	if endpoint.DNS.QueryName != "example.com." {
 		t.Error("Endpoint.dns.query-name should be formatted with . suffix")
 	}
 }
 
+func TestEndpoint_ValidateAndSetDefaultsWithSimpleErrors(t *testing.T) {
+	scenarios := []struct {
+		endpoint    *Endpoint
+		expectedErr error
+	}{
+		{
+			endpoint: &Endpoint{
+				Name:       "",
+				URL:        "https://example.com",
+				Conditions: []Condition{Condition("[STATUS] == 200")},
+			},
+			expectedErr: ErrEndpointWithNoName,
+		},
+		{
+			endpoint: &Endpoint{
+				Name:       "endpoint-with-no-url",
+				URL:        "",
+				Conditions: []Condition{Condition("[STATUS] == 200")},
+			},
+			expectedErr: ErrEndpointWithNoURL,
+		},
+		{
+			endpoint: &Endpoint{
+				Name:       "endpoint-with-no-conditions",
+				URL:        "https://example.com",
+				Conditions: nil,
+			},
+			expectedErr: ErrEndpointWithNoCondition,
+		},
+		{
+			endpoint: &Endpoint{
+				Name:       "domain-expiration-with-bad-interval",
+				URL:        "https://example.com",
+				Interval:   time.Minute,
+				Conditions: []Condition{Condition("[DOMAIN_EXPIRATION] > 720h")},
+			},
+			expectedErr: ErrInvalidEndpointIntervalForDomainExpirationPlaceholder,
+		},
+		{
+			endpoint: &Endpoint{
+				Name:       "domain-expiration-with-good-interval",
+				URL:        "https://example.com",
+				Interval:   5 * time.Minute,
+				Conditions: []Condition{Condition("[DOMAIN_EXPIRATION] > 720h")},
+			},
+			expectedErr: nil,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.endpoint.Name, func(t *testing.T) {
+			if err := scenario.endpoint.ValidateAndSetDefaults(); err != scenario.expectedErr {
+				t.Errorf("Expected error %v, got %v", scenario.expectedErr, err)
+			}
+		})
+	}
+}
+
 func TestEndpoint_buildHTTPRequest(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	endpoint := Endpoint{