xmpp-webhook/handler.go

141 wiersze
3.1 KiB
Go

package main
import (
"encoding/json"
"io/ioutil"
"net/http"
)
type Response struct {
Message string
Code int
}
func errorResponse() Response {
return Response{"", http.StatusInternalServerError}
}
// interface for parser functions (grafana, prometheus, ...)
type parserFunc func(*http.Request) (string, error, Response)
type messageHandler struct {
messages chan<- string // chan to xmpp client
parserFunc parserFunc
}
// http request handler
func (h *messageHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// parse/generate message from http request
m, err, response := h.parserFunc(r)
if err != nil {
w.WriteHeader(http.StatusInternalServerError)
}
// send message to xmpp client
h.messages <- m
w.WriteHeader(response.Code)
w.Write([]byte(response.Message))
}
// returns new handler with a given parser function
func newMessageHandler(m chan<- string, f parserFunc) *messageHandler {
return &messageHandler{
messages: m,
parserFunc: f,
}
}
/*************
GRAFANA PARSER
*************/
func grafanaParserFunc(r *http.Request) (string, error, Response) {
// get alert data from request
body, err := ioutil.ReadAll(r.Body)
if err != nil {
return "", err, errorResponse()
}
// grafana alert struct
alert := &struct {
Title string `json:"title"`
RuleURL string `json:"ruleUrl"`
State string `json:"state"`
Message string `json:"message"`
}{}
// parse body into the alert struct
err = json.Unmarshal(body, &alert)
if err != nil {
return "", err, errorResponse()
}
// contruct alert message
var message string
switch alert.State {
case "ok":
message = ":) " + alert.Title
default:
message = ":( " + alert.Title + "\n" + alert.Message + "\n" + alert.RuleURL
}
return message, nil, Response{"", http.StatusNoContent}
}
/*************
SLACK PARSER
*************/
type SlackMessage struct {
Channel string `json:"channel"`
IconEmoji string `json:"icon_emoji"`
Username string `json:"username"`
Text string `json:"text"`
Attachments []SlackAttachment `json:"attachments"`
}
type SlackAttachment struct {
Color string `json:"color"`
Title string `json:"title"`
TitleLink string `json:"title_link"`
Text string `json:"text"`
}
func nonemptyAppendNewline(message string) string {
if len(message) == 0 {
return message
}
return message + "\n"
}
func slackParserFunc(r *http.Request) (string, error, Response) {
// get alert data from request
body, err := ioutil.ReadAll(r.Body)
if err != nil {
return "", err, errorResponse()
}
// grafana alert struct
alert := SlackMessage{}
// parse body into the alert struct
err = json.Unmarshal(body, &alert)
if err != nil {
return "", err, Response{"", http.StatusInternalServerError}
}
// contruct alert message
message := ""
hasText := (alert.Text != "")
if hasText {
message = alert.Text
}
for _, attachment := range alert.Attachments {
message = nonemptyAppendNewline(message)
message += attachment.Title + "\n"
message += attachment.TitleLink + "\n\n"
message += attachment.Text
}
return message, nil, Response{"ok", http.StatusOK}
}