From b4e6ed658a4e55c067de4253be8fe7331555921b Mon Sep 17 00:00:00 2001
From: Kailash Nadh <kailash@nadh.in>
Date: Wed, 31 Oct 2018 19:42:07 +0530
Subject: [PATCH] Refactor and fix obsolete campaign template compilation and
 validation routines

---
 campaigns.go     | 12 ++++++------
 runner/runner.go | 24 ------------------------
 templates.go     | 22 ++++++++++++----------
 3 files changed, 18 insertions(+), 40 deletions(-)

diff --git a/campaigns.go b/campaigns.go
index c05ed03..7fa42a2 100644
--- a/campaigns.go
+++ b/campaigns.go
@@ -162,7 +162,7 @@ func handleCreateCampaign(c echo.Context) error {
 	}
 
 	// Validate.
-	if err := validateCampaignFields(o); err != nil {
+	if err := validateCampaignFields(o, app); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, err.Error())
 	}
 
@@ -235,7 +235,7 @@ func handleUpdateCampaign(c echo.Context) error {
 		return err
 	}
 
-	if err := validateCampaignFields(o); err != nil {
+	if err := validateCampaignFields(o, app); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, err.Error())
 	}
 
@@ -430,7 +430,7 @@ func handleTestCampaign(c echo.Context) error {
 		return err
 	}
 	// Validate.
-	if err := validateCampaignFields(req); err != nil {
+	if err := validateCampaignFields(req, app); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, err.Error())
 	}
 	if len(req.SubscriberEmails) == 0 {
@@ -497,7 +497,7 @@ func sendTestMessage(sub *models.Subscriber, camp *models.Campaign, app *App) er
 }
 
 // validateCampaignFields validates incoming campaign field values.
-func validateCampaignFields(c campaignReq) error {
+func validateCampaignFields(c campaignReq, app *App) error {
 	if !regexFromAddress.Match([]byte(c.FromEmail)) {
 		if !govalidator.IsEmail(c.FromEmail) {
 			return errors.New("invalid `from_email`")
@@ -522,8 +522,8 @@ func validateCampaignFields(c campaignReq) error {
 		}
 	}
 
-	_, err := runner.CompileMessageTemplate(tplTag, c.Body)
-	if err != nil {
+	camp := models.Campaign{Body: c.Body, TemplateBody: tplTag}
+	if err := c.CompileTemplate(app.Runner.TemplateFuncs(&camp)); err != nil {
 		return fmt.Errorf("Error compiling campaign body: %v", err)
 	}
 
diff --git a/runner/runner.go b/runner/runner.go
index 914ff04..8a48eba 100644
--- a/runner/runner.go
+++ b/runner/runner.go
@@ -324,27 +324,3 @@ func (r *Runner) trackLink(url, campUUID, subUUID string) string {
 
 	return fmt.Sprintf(r.cfg.LinkTrackURL, uu, campUUID, subUUID)
 }
-
-// CompileMessageTemplate takes a base template body string and a child (message) template
-// body string, compiles both and inserts the child template as the named template "content"
-// and returns the resultant template.
-func CompileMessageTemplate(baseBody, childBody string) (*template.Template, error) {
-	// Compile the base template.
-	baseTPL, err := template.New(BaseTPL).Parse(baseBody)
-	if err != nil {
-		return nil, fmt.Errorf("error compiling base template: %v", err)
-	}
-
-	// Compile the campaign message.
-	msgTpl, err := template.New(ContentTpl).Parse(childBody)
-	if err != nil {
-		return nil, fmt.Errorf("error compiling message: %v", err)
-	}
-
-	out, err := baseTPL.AddParseTree(ContentTpl, msgTpl.Tree)
-	if err != nil {
-		return nil, fmt.Errorf("error inserting child template: %v", err)
-	}
-
-	return out, nil
-}
diff --git a/templates.go b/templates.go
index 9c724bc..8273a3c 100644
--- a/templates.go
+++ b/templates.go
@@ -1,7 +1,6 @@
 package main
 
 import (
-	"bytes"
 	"errors"
 	"fmt"
 	"net/http"
@@ -10,7 +9,6 @@ import (
 
 	"github.com/asaskevich/govalidator"
 	"github.com/knadh/listmonk/models"
-	"github.com/knadh/listmonk/runner"
 	"github.com/labstack/echo"
 )
 
@@ -29,6 +27,11 @@ const (
 		<p>Here is a link to <a href="https://listmonk.app" target="_blank">listmonk</a>.</p>`
 )
 
+var dummySubscriber = models.Subscriber{
+	Email: "dummy@listmonk.app",
+	Name:  "Dummy User",
+}
+
 type dummyMessage struct {
 	UnsubscribeURL string
 }
@@ -99,20 +102,19 @@ func handlePreviewTemplate(c echo.Context) error {
 	}
 
 	// Compile the template.
-	tpl, err := runner.CompileMessageTemplate(body, dummyTpl)
-	if err != nil {
+	camp := models.Campaign{TemplateBody: body, Body: dummyTpl}
+	if err := camp.CompileTemplate(app.Runner.TemplateFuncs(&camp)); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Error compiling template: %v", err))
 	}
 
 	// Render the message body.
-	var out = bytes.Buffer{}
-	if err := tpl.ExecuteTemplate(&out,
-		runner.BaseTPL,
-		dummyMessage{UnsubscribeURL: "#dummy"}); err != nil {
-		return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Error executing template: %v", err))
+	m := app.Runner.NewMessage(&camp, &dummySubscriber)
+	if err := m.Render(); err != nil {
+		return echo.NewHTTPError(http.StatusBadRequest,
+			fmt.Sprintf("Error rendering message: %v", err))
 	}
 
-	return c.HTML(http.StatusOK, out.String())
+	return c.HTML(http.StatusOK, string(m.Body))
 }
 
 // handleCreateTemplate handles template creation.