Add support for [BODY] placeholder and basic JSON path support

Note that arrays are not currently supported, same with asterisks

README.md

@@ -37,13 +37,15 @@ Note that you can also add environment variables in the your configuration file
 
 Here are some examples of conditions you can use:
 
-| Condition                             | Description                               | Values that would pass | Values that would fail |
+| Condition                             | Description                               | Values that would pass   | Values that would fail  |
-| ------------------------------------- | ----------------------------------------- | ---------------------- | ---------------------- |
+| ------------------------------------- | ----------------------------------------- | ------------------------ | ----------------------- |
-| `[STATUS] == 200`                     | Status must be equal to 200               | 200                    | 201, 404, 500          |
+| `[STATUS] == 200`                     | Status must be equal to 200               | 200                      | 201, 404, 500           |
-| `[STATUS] < 300`                      | Status must lower than 300                | 200, 201, 299          | 301, 302, 400, 500     |
+| `[STATUS] < 300`                      | Status must lower than 300                | 200, 201, 299            | 301, 302, 400, 500      |
-| `[STATUS] <= 299`                     | Status must be less than or equal to 299  | 200, 201, 299          | 301, 302, 400, 500     |
+| `[STATUS] <= 299`                     | Status must be less than or equal to 299  | 200, 201, 299            | 301, 302, 400, 500      |
-| `[STATUS] > 400`                      | Status must be greater than 400           | 401, 402, 403, 404     | 200, 201, 300, 400     |
+| `[STATUS] > 400`                      | Status must be greater than 400           | 401, 402, 403, 404       | 200, 201, 300, 400      |
-| `[RESPONSE_TIME] < 500`               | Response time must be below 500ms         | 100ms, 200ms, 300ms    | 500ms, 1500ms          |
+| `[RESPONSE_TIME] < 500`               | Response time must be below 500ms         | 100ms, 200ms, 300ms      | 500ms, 1500ms           |
+| `[BODY] == 1`                         | The body must be equal to 1               | 1                        | literally anything else |
+| (beta) `[BODY].data.id == 1`          | The jsonpath `$.data.id` is equal to 1    | `{ "data" : { "id": 1 }` | literally anything else |
 
 
 ## Docker

config.yaml

@@ -5,7 +5,8 @@ services:
     interval: 10s
     conditions:
       - "[STATUS] == 200"
-      - "[RESPONSE_TIME] < 30"
+      - "[RESPONSE_TIME] < 500"
+      - "[BODY].status == UP"
   - name: Example
     url: https://example.org/
     interval: 30s

core/types.go

@@ -2,6 +2,8 @@ package core
 
 import (
 	"fmt"
+	"github.com/TwinProduction/gatus/jsonpath"
+	"io/ioutil"
 	"net"
 	"net/http"
 	"net/url"
@@ -14,6 +16,7 @@ const (
 	StatusPlaceholder       = "[STATUS]"
 	IPPlaceHolder           = "[IP]"
 	ResponseTimePlaceHolder = "[RESPONSE_TIME]"
+	BodyPlaceHolder         = "[BODY]"
 )
 
 type HealthStatus struct {
@@ -21,13 +24,9 @@ type HealthStatus struct {
 	Message string `json:"message,omitempty"`
 }
 
-type ServerMessage struct {
-	Error   bool   `json:"error"`
-	Message string `json:"message"`
-}
-
 type Result struct {
 	HttpStatus       int                `json:"status"`
+	Body             []byte             `json:"-"`
 	Hostname         string             `json:"hostname"`
 	Ip               string             `json:"-"`
 	Duration         time.Duration      `json:"duration"`
@@ -59,7 +58,8 @@ func (service *Service) getIp(result *Result) {
 	result.Ip = ips[0].String()
 }
 
-func (service *Service) getStatus(result *Result) {
+func (service *Service) call(result *Result) {
+	// TODO: re-use the same client instead of creating multiple clients
 	client := &http.Client{
 		Timeout: time.Second * 10,
 	}
@@ -71,13 +71,17 @@ func (service *Service) getStatus(result *Result) {
 	}
 	result.Duration = time.Now().Sub(startTime)
 	result.HttpStatus = response.StatusCode
+	result.Body, err = ioutil.ReadAll(response.Body)
+	if err != nil {
+		result.Errors = append(result.Errors, err.Error())
+	}
 }
 
 func (service *Service) EvaluateConditions() *Result {
 	result := &Result{Success: true, Errors: []string{}}
 	service.getIp(result)
 	if len(result.Errors) == 0 {
-		service.getStatus(result)
+		service.call(result)
 	} else {
 		result.Success = false
 	}
@@ -138,7 +142,13 @@ func sanitizeAndResolve(list []string, result *Result) []string {
 			element = result.Ip
 		case ResponseTimePlaceHolder:
 			element = strconv.Itoa(int(result.Duration.Milliseconds()))
+		case BodyPlaceHolder:
+			element = string(result.Body)
 		default:
+			// if starts with BodyPlaceHolder, then do the jsonpath thingy
+			if strings.HasPrefix(element, BodyPlaceHolder) {
+				element = jsonpath.Eval(strings.Replace(element, fmt.Sprintf("%s.", BodyPlaceHolder), "", 1), result.Body)
+			}
 		}
 		sanitizedList = append(sanitizedList, element)
 	}

core/types_test.go

@@ -86,11 +86,83 @@ func TestEvaluateWithResponseTimeUsingLessThanOrEqualTo(t *testing.T) {
 	}
 }
 
+func TestEvaluateWithBody(t *testing.T) {
+	condition := Condition("[BODY] == test")
+	result := &Result{Body: []byte("test")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPath(t *testing.T) {
+	condition := Condition("[BODY].status == UP")
+	result := &Result{Body: []byte("{\"status\":\"UP\"}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPathComplex(t *testing.T) {
+	condition := Condition("[BODY].data.name == john")
+	result := &Result{Body: []byte("{\"data\": {\"id\": 1, \"name\": \"john\"}}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPathComplexInt(t *testing.T) {
+	condition := Condition("[BODY].data.id == 1")
+	result := &Result{Body: []byte("{\"data\": {\"id\": 1}}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPathComplexIntUsingGreaterThan(t *testing.T) {
+	condition := Condition("[BODY].data.id > 0")
+	result := &Result{Body: []byte("{\"data\": {\"id\": 1}}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPathComplexIntFailureUsingGreaterThan(t *testing.T) {
+	condition := Condition("[BODY].data.id > 5")
+	result := &Result{Body: []byte("{\"data\": {\"id\": 1}}")}
+	condition.evaluate(result)
+	if result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a failure", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPathComplexIntUsingLessThan(t *testing.T) {
+	condition := Condition("[BODY].data.id < 5")
+	result := &Result{Body: []byte("{\"data\": {\"id\": 2}}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+}
+
+func TestEvaluateWithBodyJsonPathComplexIntFailureUsingLessThan(t *testing.T) {
+	condition := Condition("[BODY].data.id < 5")
+	result := &Result{Body: []byte("{\"data\": {\"id\": 10}}")}
+	condition.evaluate(result)
+	if result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a failure", condition)
+	}
+}
+
 func TestIntegrationEvaluateConditions(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "GitHub",
+		Name:       "TwiNNatioN",
-		Url:        "https://api.github.com/healthz",
+		Url:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 	}
 	result := service.EvaluateConditions()
@@ -105,8 +177,8 @@ func TestIntegrationEvaluateConditions(t *testing.T) {
 func TestIntegrationEvaluateConditionsWithFailure(t *testing.T) {
 	condition := Condition("[STATUS] == 500")
 	service := Service{
-		Name:       "GitHub",
+		Name:       "TwiNNatioN",
-		Url:        "https://api.github.com/healthz",
+		Url:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 	}
 	result := service.EvaluateConditions()

jsonpath/jsonpath.go

@@ -0,0 +1,30 @@
+package jsonpath
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+func Eval(path string, b []byte) string {
+	var object map[string]interface{}
+	err := json.Unmarshal(b, &object)
+	if err != nil {
+		return ""
+	}
+	return walk(path, object)
+}
+
+func walk(path string, object map[string]interface{}) string {
+	keys := strings.Split(path, ".")
+	targetKey := keys[0]
+	// if there's only one key and the target key is that key, then return its value
+	if len(keys) == 1 {
+		return fmt.Sprintf("%v", object[targetKey])
+	}
+	// if there's more than one key, then walk deeper
+	if len(keys) > 0 {
+		return walk(strings.Replace(path, fmt.Sprintf("%s.", targetKey), "", 1), object[targetKey].(map[string]interface{}))
+	}
+	return ""
+}