fix: fix multiline template rendering and add test (#59)

_docs/data/data.yaml

@@ -36,8 +36,16 @@ properties:
       Golang template for the message. The [Metadata struct](https://pkg.go.dev/github.com/thegeeklab/wp-plugin-go/plugin#Metadata)
       is exposed to the template and all fields can be referenced. To extend the functionality, [sprig functions](https://masterminds.github.io/sprig/) can also be used.
     defaultValue: |
-      Status: **{{ .Pipeline.Status }}**<br/>
-      Build: [{{ .Repository.Slug }}]({{ .Pipeline.URL }}){{ if .Curr.Branch }} ({{ .Curr.Branch }}){{ end }} by {{ .Curr.Author.Name }}<br/>
+      Status: **{{ .Pipeline.Status }}**
+      Build: [{{ .Repository.Slug }}]({{ .Pipeline.URL }}){{ if .Curr.Branch }} ({{ .Curr.Branch }}){{ end }} by {{ .Curr.Author.Name }}
       Message: {{ .Curr.Message }}{{ if .Curr.URL }} ([source]({{ .Curr.URL }})){{ end }}
     type: string
     required: false
+
+  - name: template_unsafe
+    description: |
+      By default, raw HTML and potentially dangerous links in the template are not rendered. If you want to use inline HTML, you may need to turn this on.
+      In such cases, please ensure that the CI configuration files in the Git repository are protected against malicious changes.
+    defaultValue: false
+    type: bool
+    required: false

cmd/wp-matrix/config.go

@@ -11,13 +11,6 @@ import (
 	"github.com/urfave/cli/v2"
 )
 
-//nolint:lll
-const defaultTemplate = `
-Status: **{{ .Pipeline.Status }}**<br/>
-Build: [{{ .Repository.Slug }}]({{ .Pipeline.URL }}){{ if .Curr.Branch }} ({{ .Curr.Branch }}){{ end }} by {{ .Curr.Author.Name }}<br/>
-Message: {{ .Curr.Title }}{{ if .Curr.URL }} ([source]({{ .Curr.URL }})){{ end }}
-`
-
 // settingsFlags has the cli.Flags for the plugin.Settings.
 func settingsFlags(settings *plugin.Settings, category string) []cli.Flag {
 	return []cli.Flag{
@@ -68,9 +61,16 @@ func settingsFlags(settings *plugin.Settings, category string) []cli.Flag {
 			Name:        "template",
 			EnvVars:     []string{"PLUGIN_TEMPLATE", "MATRIX_TEMPLATE"},
 			Usage:       "message template",
-			Value:       defaultTemplate,
+			Value:       plugin.DefaultMessageTemplate,
 			Destination: &settings.Template,
 			Category:    category,
 		},
+		&cli.BoolFlag{
+			Name:        "template-unsafe",
+			EnvVars:     []string{"PLUGIN_TEMPLATE_UNSAFE", "MATRIX_TEMPLATE_UNSAFE"},
+			Usage:       "render raw HTML and potentially dangerous links in template",
+			Destination: &settings.TemplateUnsafe,
+			Category:    category,
+		},
 	}
 }

plugin/impl.go

@@ -10,6 +10,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"net/http"
 	"strings"
 
 	"github.com/microcosm-cc/bluemonday"
@@ -75,14 +76,11 @@ func (p *Plugin) Execute() error {
 		return fmt.Errorf("failed to join room: %w", err)
 	}
 
-	message, err := template.RenderTrim(p.Network.Context, *p.Network.Client, p.Settings.Template, p.Metadata)
+	content, err := p.messageContent(p.Network.Context, *p.Network.Client)
 	if err != nil {
 		return fmt.Errorf("failed to render template: %w", err)
 	}
 
-	formatted := bluemonday.UGCPolicy().SanitizeBytes([]byte(message))
-	content := format.RenderMarkdown(string(formatted), true, false)
-
 	if _, err := client.SendMessageEvent(joined.RoomID, event.EventMessage, content); err != nil {
 		return fmt.Errorf("failed to submit message: %w", err)
 	}
@@ -92,6 +90,26 @@ func (p *Plugin) Execute() error {
 	return nil
 }
 
+func (p *Plugin) messageContent(ctx context.Context, client http.Client) (event.MessageEventContent, error) {
+	message, err := template.RenderTrim(ctx, client, p.Settings.Template, p.Metadata)
+	if err != nil {
+		return event.MessageEventContent{}, err
+	}
+
+	content := format.RenderMarkdown(message, true, p.Settings.TemplateUnsafe)
+
+	safeBody := format.HTMLToMarkdown(bluemonday.UGCPolicy().Sanitize(content.FormattedBody))
+	if content.Body != safeBody {
+		content.Body = safeBody
+	}
+
+	if content.FormattedBody != "" {
+		content.FormattedBody = bluemonday.UGCPolicy().Sanitize(content.FormattedBody)
+	}
+
+	return content, nil
+}
+
 func prepend(prefix, input string) string {
 	if strings.TrimSpace(input) == "" {
 		return input

plugin/impl_test.go

@@ -0,0 +1,78 @@
+package plugin
+
+import (
+	"context"
+	"net/http"
+	"testing"
+
+	wp "github.com/thegeeklab/wp-plugin-go/plugin"
+)
+
+func Test_messageContent(t *testing.T) {
+	//nolint:lll
+	tests := []struct {
+		name     string
+		want     string
+		unsafe   bool
+		template string
+		meta     wp.Metadata
+	}{
+		{
+			name:     "render default template",
+			want:     "Status: **success**\nBuild: [octocat/demo](https://ci.example.com) (main) by octobot\nMessage: feat: demo commit title ([source](https://git.example.com))",
+			template: DefaultMessageTemplate,
+		},
+		{
+			name:     "render unsafe html template",
+			want:     "Status: **success**\nBuild: octocat/demo",
+			unsafe:   true,
+			template: "Status: **{{ .Pipeline.Status }}**<br>Build: {{ .Repository.Slug }}",
+		},
+		{
+			name:     "render html xss template",
+			want:     "Status: **success**\nBuild: octocat/demo",
+			unsafe:   true,
+			template: "Status: **{{ .Pipeline.Status }}**<br>Build: <a href=\"javascript:alert('XSS1')\" onmouseover=\"alert('XSS2')\">{{ .Repository.Slug }}<a>",
+		},
+		{
+			name:     "render markdown xss template",
+			want:     "Status: **success**\nBuild: octocat/demo",
+			unsafe:   true,
+			template: "Status: **{{ .Pipeline.Status }}**<br>Build: [{{ .Repository.Slug }}](javascript:alert(XSS1'))",
+		},
+	}
+
+	options := wp.Options{
+		Name:    "wp-matrix",
+		Execute: func(ctx context.Context) error { return nil },
+	}
+
+	p := New(options, &Settings{})
+	p.Metadata = wp.Metadata{
+		Curr: wp.Commit{
+			Branch: "main",
+			Title:  "feat: demo commit title",
+			URL:    "https://git.example.com",
+			Author: wp.Author{
+				Name: "octobot",
+			},
+		},
+		Pipeline: wp.Pipeline{
+			Status: "success",
+			URL:    "https://ci.example.com",
+		},
+		Repository: wp.Repository{
+			Slug: "octocat/demo",
+		},
+	}
+
+	for _, tt := range tests {
+		p.Settings.Template = tt.template
+		p.Settings.TemplateUnsafe = tt.unsafe
+		content, _ := p.messageContent(context.Background(), http.Client{})
+
+		if content.Body != tt.want {
+			t.Errorf("messageContent: %q got: %q, want: %q", tt.name, content.Body, tt.want)
+		}
+	}
+}

plugin/plugin.go

@@ -10,6 +10,13 @@ import (
 	wp "github.com/thegeeklab/wp-plugin-go/plugin"
 )
 
+//nolint:lll
+const DefaultMessageTemplate = `
+Status: **{{ .Pipeline.Status }}**
+Build: [{{ .Repository.Slug }}]({{ .Pipeline.URL }}){{ if .Curr.Branch }} ({{ .Curr.Branch }}){{ end }} by {{ .Curr.Author.Name }}
+Message: {{ .Curr.Title }}{{ if .Curr.URL }} ([source]({{ .Curr.URL }})){{ end }}
+`
+
 // Plugin implements provide the plugin.
 type Plugin struct {
 	*wp.Plugin
@@ -25,6 +32,7 @@ type Settings struct {
 	Homeserver     string
 	RoomID         string
 	Template       string
+	TemplateUnsafe bool
 }
 
 func New(options wp.Options, settings *Settings) *Plugin {