Add support for generic templates by using custom extra vars (#84)

* Fix DOCS.md example configuration with custom message from file

* Move .test.message to a better named file

* Add support for additional, custom extra vars to be used in the message template

* Add cmdline/envvars to support the extra vars

* Enhance DOCS.md with example configuration using generic template file with custom vars

* Add testcase for custom template vars

DOCS.md

@@ -152,11 +152,37 @@ Example configuration with a custom message template:
 Example configuration with a custom message template loaded from file:
 
 ```diff
-  image: appleboy/drone-telegram
+  - name: send telegram notification
-  settings:
+    image: appleboy/drone-telegram
-    token: xxxxxxxxxx
+    settings:
-    to: telegram_user_id
+      token: xxxxxxxxxx
-+   message_file: message_file.tpl
+      to: telegram_user_id
++     message_file: message_file.tpl
+```
+
+Example configuration with a generic message template loaded from file, with additional extra vars:
+
+```diff
+  - name: send telegram notification
+    image: appleboy/drone-telegram
+    settings:
+      token: xxxxxxxxxx
+      to: telegram_user_id
++     message_file: message_file.tpl
++     template_vars:
++       env: testing
++       app: MyApp
+```
+
+Where `message_file.tpl` is:
+```
+Build finished for *{{tpl.app}}* - *{{tpl.env}}*
+
+{{#success build.status}}
+  build {{build.number}} succeeded. Good job.
+{{else}}
+  build {{build.number}} failed. Fix me please.
+{{/success}}
 ```
 
 ## Parameter Reference
@@ -173,6 +199,9 @@ message
 message_file
 : overwrite the default message template with the contents of the specified file
 
+template_vars
+: define additional template vars. Example: `var1: hello` can be used within the template as `tpl.var1`
+
 photo
 : local file path
 

main.go

@@ -41,6 +41,11 @@ func main() {
 			Usage:  "send telegram message from file",
 			EnvVar: "PLUGIN_MESSAGE_FILE,TELEGRAM_MESSAGE_FILE,INPUT_MESSAGE_FILE",
 		},
+		cli.StringFlag{
+			Name:   "template.vars",
+			Usage:  "additional template vars to be used in message, as JSON string",
+			EnvVar: "PLUGIN_TEMPLATE_VARS,TELEGRAM_TEMPLATE_VARS,INPUT_TEMPLATE_VARS",
+		},
 		cli.StringSliceFlag{
 			Name:   "photo",
 			Usage:  "send photo message",
@@ -287,23 +292,24 @@ func run(c *cli.Context) error {
 			DeployTo: c.String("deploy.to"),
 		},
 		Config: Config{
-			Token:       c.String("token"),
+			Token:        c.String("token"),
-			Debug:       c.Bool("debug"),
+			Debug:        c.Bool("debug"),
-			MatchEmail:  c.Bool("match.email"),
+			MatchEmail:   c.Bool("match.email"),
-			WebPreview:  c.Bool("webpage.preview"),
+			WebPreview:   c.Bool("webpage.preview"),
-			To:          c.StringSlice("to"),
+			To:           c.StringSlice("to"),
-			Message:     c.StringSlice("message"),
+			Message:      c.StringSlice("message"),
-			MessageFile: c.String("message.file"),
+			MessageFile:  c.String("message.file"),
-			Photo:       c.StringSlice("photo"),
+			TemplateVars: c.String("template.vars"),
-			Document:    c.StringSlice("document"),
+			Photo:        c.StringSlice("photo"),
-			Sticker:     c.StringSlice("sticker"),
+			Document:     c.StringSlice("document"),
-			Audio:       c.StringSlice("audio"),
+			Sticker:      c.StringSlice("sticker"),
-			Voice:       c.StringSlice("voice"),
+			Audio:        c.StringSlice("audio"),
-			Location:    c.StringSlice("location"),
+			Voice:        c.StringSlice("voice"),
-			Video:       c.StringSlice("video"),
+			Location:     c.StringSlice("location"),
-			Venue:       c.StringSlice("venue"),
+			Video:        c.StringSlice("video"),
-			Format:      c.String("format"),
+			Venue:        c.StringSlice("venue"),
-			GitHub:      c.Bool("github"),
+			Format:       c.String("format"),
+			GitHub:       c.Bool("github"),
 		},
 	}
 

plugin.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bufio"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -59,23 +60,24 @@ type (
 
 	// Config for the plugin.
 	Config struct {
-		Token       string
+		Token        string
-		Debug       bool
+		Debug        bool
-		MatchEmail  bool
+		MatchEmail   bool
-		WebPreview  bool
+		WebPreview   bool
-		To          []string
+		To           []string
-		Message     []string
+		Message      []string
-		MessageFile string
+		MessageFile  string
-		Photo       []string
+		TemplateVars string
-		Document    []string
+		Photo        []string
-		Sticker     []string
+		Document     []string
-		Audio       []string
+		Sticker      []string
-		Voice       []string
+		Audio        []string
-		Location    []string
+		Voice        []string
-		Video       []string
+		Location     []string
-		Venue       []string
+		Video        []string
-		Format      string
+		Venue        []string
-		GitHub      bool
+		Format       string
+		GitHub       bool
 	}
 
 	// Plugin values.
@@ -85,6 +87,7 @@ type (
 		Commit Commit
 		Build  Build
 		Config Config
+		Tpl    map[string]string
 	}
 
 	// Location format
@@ -258,9 +261,16 @@ func (p Plugin) Exec() (err error) {
 		message = p.Message()
 	}
 
+	if p.Config.TemplateVars != "" {
+		p.Tpl = make(map[string]string)
+		if err = json.Unmarshal([]byte(p.Config.TemplateVars), &p.Tpl); err != nil {
+			return fmt.Errorf("unable to unmarshall template vars from JSON string '%s': %v", p.Config.TemplateVars, err)
+		}
+	}
+
 	var bot *tgbotapi.BotAPI
 	if bot, err = tgbotapi.NewBotAPI(p.Config.Token); err != nil {
-		return err
+		return
 	}
 
 	bot.Debug = p.Config.Debug

plugin_test.go

@@ -347,7 +347,38 @@ func TestMessageFile(t *testing.T) {
 		Config: Config{
 			Token:       os.Getenv("TELEGRAM_TOKEN"),
 			To:          []string{os.Getenv("TELEGRAM_TO")},
-			MessageFile: "tests/.test.message",
+			MessageFile: "tests/message.txt",
+		},
+	}
+
+	err := plugin.Exec()
+	assert.Nil(t, err)
+}
+
+func TestTemplateVars(t *testing.T) {
+	plugin := Plugin{
+		Repo: Repo{
+			Name:      "go-hello",
+			Namespace: "appleboy",
+		},
+		Commit: Commit{
+			Sha:     "e7c4f0a63ceeb42a39ac7806f7b51f3f0d204fd2",
+			Author:  "Bo-Yi Wu",
+			Branch:  "master",
+			Message: "This is a test commit msg",
+		},
+		Build: Build{
+			Number: 101,
+			Status: "success",
+			Link:   "https://github.com/appleboy/go-hello",
+		},
+
+		Config: Config{
+			Token:        os.Getenv("TELEGRAM_TOKEN"),
+			To:           []string{os.Getenv("TELEGRAM_TO")},
+			Format:       "markdown",
+			MessageFile:  "tests/message_template.txt",
+			TemplateVars: `{"env":"testing","version":"1.2.0-SNAPSHOT"}`,
 		},
 	}
 

tests/message_template.txt

@@ -0,0 +1,7 @@
+Sample message template loaded from file.
+
+*Environ:* {{tpl.env}}
+*Version:* {{tpl.version}}
+
+Commit msg:  {{commit.message}}
+