Improve documentation and panic on invalid service

README.md

@@ -15,6 +15,8 @@ By default, the configuration file is expected to be at `config/config.yaml`.
 
 You can specify a custom path by setting the `GATUS_CONFIG_FILE` environment variable.
 
+Here's a simple example:
+
 ```yaml
 metrics: true         # Whether to expose metrics at /metrics
 services:
@@ -23,13 +25,9 @@ services:
     interval: 15s     # Duration to wait between every status check (default: 10s)
     conditions:
       - "[STATUS] == 200"         # Status must be 200
+      - "[BODY].status == UP"     # The json path "$.status" must be equal to UP
       - "[RESPONSE_TIME] < 300"   # Response time must be under 300ms
-  - name: github
-    url: https://api.github.com/healthz
-    interval: 2m
-    conditions:
-      - "[STATUS] == 200"
-  - name: Example
+  - name: example
     url: https://example.org/
     interval: 30s
     conditions:
@@ -39,6 +37,20 @@ services:
 Note that you can also add environment variables in the your configuration file (i.e. `$DOMAIN`, `${DOMAIN}`)
 
 
+### Configuration
+
+| Parameter               | Description | Default |
+| ----------------------- | ------------------------------------------------------ | -------------- |
+| `metrics`               | Whether to expose metrics at /metrics                  | `false`
+| `services[].name`       | Name of the service. Can be anything.                  | Required `""`
+| `services[].url`        | URL to send the request to                             | Required `""`
+| `services[].conditions` | Conditions used to determine the health of the service | `[]`
+| `services[].interval`   | Duration to wait between every status check            | `10s`
+| `services[].method`     | Request method                                         | `GET`
+| `services[].body`       | Request body                                           | `""`
+| `services[].headers`    | Request headers                                        | `{}` 
+
+
 ### Conditions
 
 Here are some examples of conditions you can use:
@@ -52,6 +64,7 @@ Here are some examples of conditions you can use:
 | `[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 |
 | `[BODY].data.id == 1`                 | The jsonpath `$.data.id` is equal to 1    | `{"data":{"id":1}}`      | literally anything else |
+| `[BODY].data[0].id == 1`              | The jsonpath `$.data[0].id` is equal to 1 | `{"data":[{"id":1}]}`    | literally anything else |
 
 **NOTE**: `[BODY]` with JSON path (i.e. `[BODY].id == 1`) is currently in BETA. For the most part, the only thing that doesn't work is arrays.
 

config.yaml

@@ -1,21 +1,21 @@
 metrics: true
 services:
-#  - name: twinnation
-#    interval: 10s
-#    url: https://twinnation.org/health
-#    conditions:
-#      - "[STATUS] == 200"
-#      - "[RESPONSE_TIME] < 1000"
-#      - "[BODY].status == UP"
-  - name: twinnation-articles-api
+  - name: twinnation
     interval: 10s
-    url: https://twinnation.org/api/v1/articles
+    url: https://twinnation.org/health
+    conditions:
+      - "[STATUS] == 200"
+      - "[BODY].status == UP"
+      - "[RESPONSE_TIME] < 1000"
+  - name: twinnation-articles-api
+    interval: 10s
+    url: https://twinnation.org/api/v1/articles/24
+    conditions:
+      - "[STATUS] == 200"
+      - "[BODY].id == 24"
+      - "[BODY].tags[0] == spring"
+  - name: example
+    url: https://example.org/
+    interval: 30s
     conditions:
       - "[STATUS] == 200"
-      - "[BODY].[0].id == 42"
-
-#  - name: example
-#    url: https://example.org/
-#    interval: 30s
-#    conditions:
-#      - "[STATUS] == 200"

core/service.go

@@ -2,6 +2,7 @@ package core
 
 import (
 	"bytes"
+	"errors"
 	"github.com/TwinProduction/gatus/client"
 	"io/ioutil"
 	"net"
@@ -10,13 +11,18 @@ import (
 	"time"
 )
 
+var (
+	ErrNoCondition = errors.New("you must specify at least one condition per service")
+	ErrNoUrl       = errors.New("you must specify an url for each service")
+)
+
 type Service struct {
 	Name       string            `yaml:"name"`
-	Interval   time.Duration     `yaml:"interval,omitempty"`
 	Url        string            `yaml:"url"`
 	Method     string            `yaml:"method,omitempty"`
 	Body       string            `yaml:"body,omitempty"`
-	Headers    map[string]string `yaml:"headers"`
+	Headers    map[string]string `yaml:"headers,omitempty"`
+	Interval   time.Duration     `yaml:"interval,omitempty"`
 	Conditions []*Condition      `yaml:"conditions"`
 }
 
@@ -28,6 +34,15 @@ func (service *Service) Validate() {
 	if len(service.Method) == 0 {
 		service.Method = http.MethodGet
 	}
+	if len(service.Headers) == 0 {
+		service.Headers = make(map[string]string)
+	}
+	if len(service.Url) == 0 {
+		panic(ErrNoUrl)
+	}
+	if len(service.Conditions) == 0 {
+		panic(ErrNoCondition)
+	}
 
 	// Make sure that the request can be created
 	_, err := http.NewRequest(service.Method, service.Url, bytes.NewBuffer([]byte(service.Body)))