added more customization options

DOCS.md

@@ -4,6 +4,8 @@ You will need to supply Drone with outgoing Webhook URLs.
 The following parameters are used to configure outgoing Webhooks:
 
 * `urls` - JSON payloads are sent to each URL listed here
+* `method` - HTTP request method. Defaults to `POST`
+* `header` - HTTP request header map
 
 The following is a sample Webhook configuration in your .drone.yml file:
 
@@ -13,6 +15,8 @@ notify:
     urls:
       - https://your.webhook/...
       - https://your.other.webhook/...
+    header:
+      Authorization: pa55word
 ```
 
 The following is an example Webhook payload (whitespace added):
@@ -58,3 +62,25 @@ The following is an example Webhook payload (whitespace added):
     }
 }
 ```
+
+## Custom Body
+
+In some cases you may want to submit a custom payload in the body of your hook. For the use case we expose the following additional parameters:
+
+* `template` - Go template to create a custom payload body. See [docs](https://golang.org/pkg/text/template/)
+* `content_type` - HTTP request content type
+
+Example configuration that generate a custom Yaml payload:
+
+```yaml
+notify:
+  webhook:
+    urls:
+      - https://your.webhook/...
+      - https://your.other.webhook/...
+    content_type: application/yaml
+    template: >
+      repo: {{.Repo.FullName}}
+      build: {{.Build.Number}}
+      commit: {{.Build.Commit}}
+```

main.go

@@ -3,18 +3,25 @@ package main
 import (
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"net/http"
+	"net/url"
 	"os"
+	"text/template"
 
-	"github.com/drone/drone-go/plugin"
 	"github.com/drone/drone-go/drone"
+	"github.com/drone/drone-go/plugin"
 )
 
 func main() {
 	var repo = drone.Repo{}
 	var build = drone.Build{}
 	var vargs = struct {
-		Urls []string `json:"urls"`
+		Urls        []string          `json:"urls"`
+		Headers     map[string]string `json:"header"`
+		Method      string            `json:"method"`
+		Template    string            `json:"template"`
+		ContentType string            `json:"content_type"`
 	}{}
 
 	plugin.Param("repo", &repo)
@@ -28,16 +35,56 @@ func main() {
 		Build drone.Build `json:"build"`
 	}{repo, build}
 
-	// json payload that will be posted
-	payload, err := json.Marshal(&data)
-	if err != nil {
-		os.Exit(1)
+	// set default values
+	if len(vargs.Method) == 0 {
+		vargs.Method = "POST"
+	}
+	if len(vargs.ContentType) == 0 {
+		vargs.ContentType = "application/json"
+	}
+
+	// creates the payload. by default the payload
+	// is the build details in json format, but a custom
+	// template may also be used.
+	var buf bytes.Buffer
+	if len(vargs.Template) == 0 {
+		json.NewEncoder(&buf).Encode(&data)
+
+	} else {
+		t, err := template.New("_").Parse(vargs.Template)
+		if err != nil {
+			fmt.Printf("Error parsing content template. %s\n", err)
+			os.Exit(1)
+		}
+		t.Execute(&buf, &data)
+		if err != nil {
+			fmt.Printf("Error executing content template. %s\n", err)
+			os.Exit(1)
+		}
 	}
 
 	// post payload to each url
-	for _, url := range vargs.Urls {
-		resp, err := http.Post(url, "application/json", bytes.NewBuffer(payload))
+	for _, rawurl := range vargs.Urls {
+
+		uri, err := url.Parse(rawurl)
 		if err != nil {
+			fmt.Printf("Error parsing hook url. %s\n", err)
+			os.Exit(1)
+		}
+
+		req, err := http.NewRequest(vargs.Method, uri.String(), &buf)
+		if err != nil {
+			fmt.Printf("Error creating http request. %s\n", err)
+			os.Exit(1)
+		}
+		req.Header.Set("Content-Type", vargs.ContentType)
+		for key, value := range vargs.Headers {
+			req.Header.Set(key, value)
+		}
+
+		resp, err := http.DefaultClient.Do(req)
+		if err != nil {
+			fmt.Printf("Error executing http request. %s\n", err)
 			os.Exit(1)
 		}
 		resp.Body.Close()