feat: added beforeResponse and afterResponse hooks

config/v001.go

@@ -4,6 +4,7 @@ import "gopkg.in/yaml.v2"
 
 // ConfigV001 describes the V 0.0.1 configuration yaml
 type ConfigV001 struct {
+	Hooks  Hooks             `yaml:"hooks"`
 	Routes []ConfigV001Route `yaml:"routes"`
 }
 
@@ -14,6 +15,17 @@ type ConfigV001Route struct {
 	Size     	 string   `yaml:"size"`
 	Template 	 string   `yaml:"template"`
 	CacheControl string   `yaml:"cache-control"`
+	Hooks        []Hooks  `yaml:"hooks"`
+}
+
+type Hooks struct {
+	BeforeResponse ResponseHook `yaml:"beforeResponse"`
+	AfterResponse  ResponseHook `yaml:"afterResponse"`
+}
+
+type ResponseHook struct {
+	Url 	string 			    `yaml:"url"`
+	Headers []map[string]string `yaml:"headers"`
 }
 
 // ReadV001Config returns a parsed V 0.0.1 configuration struct

controller/controller.go

@@ -2,6 +2,7 @@ package controller
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"net/http"
@@ -21,6 +22,15 @@ type ImageSize struct {
 	height float64
 }
 
+type WebHook struct {
+	Action       string `json:"action"`
+	Route        string `json:"route"`
+	Template     string `json:"template"`
+	CacheControl string `json:"cache-control"`
+	Size         string `json:"size"`
+	Params       map[string]string `json:"params"`
+}
+
 // ConfigError shows an error at frontend if configuration has some errors
 func ConfigError(c *gin.Context) {
 	c.Data(
@@ -74,10 +84,20 @@ func HandleRoutes(c *gin.Context) {
 	image := chromium.GenerateImage(tpl.String(), sizes.width, sizes.height)
 	img := bytes.NewReader(image)
 
+	conf := config.Config
+
+	if conf.Hooks.BeforeResponse.Url != "" && !isDev {
+		callHook(conf.Hooks.BeforeResponse, "beforeResponse", route, params)
+	}
+
 	if route.CacheControl != "" {
 		c.Header("Cache-Control", fmt.Sprintf(route.CacheControl))
 	}
 	c.Render(http.StatusOK, render.Reader{ContentType: "image/jpeg", ContentLength: int64(img.Len()), Reader: img})
+
+	if conf.Hooks.AfterResponse.Url != "" && !isDev {
+		callHook(conf.Hooks.AfterResponse, "afterResponse", route, params)
+	}
 }
 
 func getCurrentRouteConfig(c *gin.Context) config.ConfigV001Route {
@@ -114,3 +134,37 @@ func getImageSize(str string) ImageSize {
 		height: height,
 	}
 }
+
+func callHook(hook config.ResponseHook, action string, confRoute config.ConfigV001Route, params map[string]string) {
+	client := &http.Client{}
+
+	body, _ := json.Marshal(WebHook{
+		Action: action,
+		Route: confRoute.Path,
+		Template: confRoute.Template,
+		CacheControl: confRoute.CacheControl,
+		Size: confRoute.Size,
+		Params: params,
+	})
+
+	responseBody := bytes.NewBuffer(body)
+	req, err := http.NewRequest("POST", hook.Url, responseBody)
+	if err != nil {
+		fmt.Printf("Unable to POST hook to %s. Reason: %s", hook.Url, err)
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+
+	for _, header := range hook.Headers {
+		for k, v := range header {
+			req.Header.Set(k, v)
+		}
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		fmt.Printf("Unable to POST hook to %s. Reason: %s", hook.Url, err)
+		return
+	}
+	fmt.Println(resp.Status)
+}