Add option to send raw request body to command

The existing `entire-payload` option sends a JSON representation of the
parsed request body.  Add a new `raw-request-body` source to send the
raw request body.

Fixes #439

internal/hook/hook.go

@@ -35,6 +35,7 @@ const (
 	SourceQuery          string = "url"
 	SourceQueryAlias     string = "query"
 	SourcePayload        string = "payload"
+	SourceRawRequestBody string = "raw-request-body"
 	SourceRequest        string = "request"
 	SourceString         string = "string"
 	SourceEntirePayload  string = "entire-payload"
@@ -449,6 +450,9 @@ func (ha *Argument) Get(r *Request) (string, error) {
 	case SourceString:
 		return ha.Name, nil
 
+	case SourceRawRequestBody:
+		return string(r.Body), nil
+
 	case SourceRequest:
 		if r == nil || r.RawRequest == nil {
 			return "", errors.New("request is nil")

test/hooks.json.tmpl

@@ -168,6 +168,17 @@
       ],
     }
   },
+  {
+    "id": "txt-raw",
+    "execute-command": "{{ .Hookecho }}",
+    "command-working-directory": "/",
+    "include-command-output-in-response": true,
+    "pass-arguments-to-command": [
+      {
+        "source": "raw-request-body"
+      }
+    ]
+  },
   {
     "id": "sendgrid",
     "execute-command": "{{ .Hookecho }}",

test/hooks.yaml.tmpl

@@ -97,6 +97,13 @@
           name: "app.messages.message.#text"
         value: "Hello!!"
 
+- id: txt-raw
+  execute-command: '{{ .Hookecho }}'
+  command-working-directory: /
+  include-command-output-in-response: true
+  pass-arguments-to-command:
+  - source: raw-request-body
+
 - id: sendgrid
   execute-command: '{{ .Hookecho }}'
   command-working-directory: /

webhook_test.go

@@ -572,6 +572,25 @@ env: HOOK_head_commit.timestamp=2013-03-12T08:14:29-07:00
 		`success`,
 		``,
 	},
+	{
+		"txt-raw",
+		"txt-raw",
+		nil,
+		"POST",
+		map[string]string{"Content-Type": "text/plain"},
+		"text/plain",
+		`# FOO
+
+blah
+blah`,
+		false,
+		http.StatusOK,
+		`# FOO
+
+blah
+blah`,
+		``,
+	},
 	{
 		"payload-json-array",
 		"sendgrid",