Work on #12: Move each providers in their own packages

alerting/provider/custom/custom.go

@@ -0,0 +1,80 @@
+package custom
+
+import (
+	"bytes"
+	"fmt"
+	"github.com/TwinProduction/gatus/client"
+	"io/ioutil"
+	"net/http"
+	"strings"
+)
+
+type AlertProvider struct {
+	Url     string            `yaml:"url"`
+	Method  string            `yaml:"method,omitempty"`
+	Body    string            `yaml:"body,omitempty"`
+	Headers map[string]string `yaml:"headers,omitempty"`
+}
+
+func (provider *AlertProvider) IsValid() bool {
+	return len(provider.Url) > 0
+}
+
+func (provider *AlertProvider) buildRequest(serviceName, alertDescription string, resolved bool) *http.Request {
+	body := provider.Body
+	providerUrl := provider.Url
+	method := provider.Method
+	if strings.Contains(body, "[ALERT_DESCRIPTION]") {
+		body = strings.ReplaceAll(body, "[ALERT_DESCRIPTION]", alertDescription)
+	}
+	if strings.Contains(body, "[SERVICE_NAME]") {
+		body = strings.ReplaceAll(body, "[SERVICE_NAME]", serviceName)
+	}
+	if strings.Contains(body, "[ALERT_TRIGGERED_OR_RESOLVED]") {
+		if resolved {
+			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", "RESOLVED")
+		} else {
+			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", "TRIGGERED")
+		}
+	}
+	if strings.Contains(providerUrl, "[ALERT_DESCRIPTION]") {
+		providerUrl = strings.ReplaceAll(providerUrl, "[ALERT_DESCRIPTION]", alertDescription)
+	}
+	if strings.Contains(providerUrl, "[SERVICE_NAME]") {
+		providerUrl = strings.ReplaceAll(providerUrl, "[SERVICE_NAME]", serviceName)
+	}
+	if strings.Contains(providerUrl, "[ALERT_TRIGGERED_OR_RESOLVED]") {
+		if resolved {
+			providerUrl = strings.ReplaceAll(providerUrl, "[ALERT_TRIGGERED_OR_RESOLVED]", "RESOLVED")
+		} else {
+			providerUrl = strings.ReplaceAll(providerUrl, "[ALERT_TRIGGERED_OR_RESOLVED]", "TRIGGERED")
+		}
+	}
+	if len(method) == 0 {
+		method = "GET"
+	}
+	bodyBuffer := bytes.NewBuffer([]byte(body))
+	request, _ := http.NewRequest(method, providerUrl, bodyBuffer)
+	for k, v := range provider.Headers {
+		request.Header.Set(k, v)
+	}
+	return request
+}
+
+// Send a request to the alert provider and return the body
+func (provider *AlertProvider) Send(serviceName, alertDescription string, resolved bool) ([]byte, error) {
+	request := provider.buildRequest(serviceName, alertDescription, resolved)
+	response, err := client.GetHttpClient().Do(request)
+	if err != nil {
+		return nil, err
+	}
+	if response.StatusCode > 399 {
+		body, err := ioutil.ReadAll(response.Body)
+		if err != nil {
+			return nil, fmt.Errorf("call to provider alert returned status code %d", response.StatusCode)
+		} else {
+			return nil, fmt.Errorf("call to provider alert returned status code %d: %s", response.StatusCode, string(body))
+		}
+	}
+	return ioutil.ReadAll(response.Body)
+}