Inject params into .drone.yml.

README.md

@@ -219,6 +219,22 @@ git:
   depth: 1
 ```
 
+### Params Injection
+
+You can inject params into .drone.yml.
+
+```
+notify:
+  hipchat:
+    room: {{hipchatRoom}}
+    token: {{hipchatToken}}
+    on_started: true
+    on_success: true
+    on_failure: true
+```
+
+![params-injection](https://f.cloud.github.com/assets/1583973/2161187/2905077e-94c3-11e3-8499-a3844682c8af.png)
+
 ### Docs
 
 Coming Soon to [drone.readthedocs.org](http://drone.readthedocs.org/)

pkg/build/script/script.go

@@ -1,6 +1,8 @@
 package script
 
 import (
+	"bytes"
+	"fmt"
 	"io/ioutil"
 	"strings"
 
@@ -13,11 +15,11 @@ import (
 	"github.com/drone/drone/pkg/plugin/publish"
 )
 
-func ParseBuild(data []byte) (*Build, error) {
+func ParseBuild(data []byte, params map[string]string) (*Build, error) {
 	build := Build{}
 
 	// parse the build configuration file
-	err := goyaml.Unmarshal(data, &build)
+	err := goyaml.Unmarshal(injectParams(data, params), &build)
 	return &build, err
 }
 
@@ -27,7 +29,15 @@ func ParseBuildFile(filename string) (*Build, error) {
 		return nil, err
 	}
 
-	return ParseBuild(data)
+	return ParseBuild(data, nil)
+}
+
+// injectParams injects params into data.
+func injectParams(data []byte, params map[string]string) []byte {
+	for k, v := range params {
+		data = bytes.Replace(data, []byte(fmt.Sprintf("{{%s}}", k)), []byte(v), -1)
+	}
+	return data
 }
 
 // Build stores the configuration details for

pkg/handler/hooks.go

@@ -122,7 +122,7 @@ func Hook(w http.ResponseWriter, r *http.Request) error {
 	}
 
 	// parse the build script
-	buildscript, err := script.ParseBuild(raw)
+	buildscript, err := script.ParseBuild(raw, repo.Params)
 	if err != nil {
 		msg := "Could not parse your .drone.yml file.  It needs to be a valid drone yaml file.\n\n" + err.Error() + "\n"
 		if err := saveFailedBuild(commit, msg); err != nil {
@@ -233,7 +233,7 @@ func PullRequestHook(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// parse the build script
-	buildscript, err := script.ParseBuild(raw)
+	buildscript, err := script.ParseBuild(raw, repo.Params)
 	if err != nil {
 		// TODO if the YAML is invalid we should create a commit record
 		// with an ERROR status so that the user knows why a build wasn't