feat: moved preview-email to optional dependency (closes #454) (closes #453)

Author: titanism

index.js

@@ -9,7 +9,12 @@ const getPaths = require('get-paths');
 const { convert } = require('html-to-text');
 const juice = require('juice');
 const nodemailer = require('nodemailer');
-const previewEmail = require('preview-email');
+
+let previewEmail;
+
+try {
+  previewEmail = require('preview-email');
+} catch {}
 
 const debug = util.debuglog('email-templates');
 
@@ -337,6 +342,16 @@ class Email {
 
     if (this.config.preview) {
       debug('using `preview-email` to preview email');
+      if (typeof previewEmail !== 'function') {
+        // don't break production apps
+        // (in case someone upgrades major without reading changelog on GH releases)
+        const err = new TypeError(
+          'Optional dependency "preview-email" not installed, but required for "previewEmail" option in "email-templates" usage (e.g. set "previewEmail: false" or "npm install preview-email" to resolve)'
+        );
+        if (env === 'production') console.error(err);
+        else throw err;
+      }
+
       await (_.isObject(this.config.preview)
         ? previewEmail(message, this.config.preview)
         : previewEmail(message));

package.json

@@ -11,31 +11,31 @@
     "Nick Baugh <[email protected]> (http://niftylettuce.com)"
   ],
   "dependencies": {
-    "@ladjs/consolidate": "^1.0.1",
+    "@ladjs/consolidate": "^1.0.4",
     "@ladjs/i18n": "^8.0.3",
     "get-paths": "^0.0.7",
     "html-to-text": "^9.0.5",
-    "juice": "^9.0.0",
+    "juice": "^10.0.0",
     "lodash": "^4.17.21",
-    "nodemailer": "^6.9.3",
-    "preview-email": "^3.0.17"
+    "nodemailer": "^6.9.14"
   },
   "devDependencies": {
-    "@commitlint/cli": "^17.6.5",
-    "@commitlint/config-conventional": "^17.6.5",
+    "@commitlint/cli": "^19.3.0",
+    "@commitlint/config-conventional": "^19.2.2",
     "ava": "^5.3.0",
     "cheerio": "^1.0.0-rc.12",
     "cross-env": "^7.0.3",
-    "ejs": "^3.1.9",
+    "ejs": "^3.1.10",
     "eslint": "^8.42.0",
     "eslint-config-xo-lass": "^2.0.1",
     "fixpack": "^4.0.0",
     "husky": "^8.0.3",
     "lint-staged": "^13.2.2",
     "nodemailer-sendgrid": "^1.0.3",
     "nyc": "^15.1.0",
-    "pug": "^3.0.2",
-    "remark-cli": "^11.0.0",
+    "preview-email": "^3.0.17",
+    "pug": "^3.0.3",
+    "remark-cli": "11.0.0",
     "remark-preset-github": "^4.0.4",
     "xo": "^0.54.2"
   },
@@ -67,6 +67,9 @@
   ],
   "license": "MIT",
   "main": "index.js",
+  "optionalDependencies": {
+    "preview-email": "*"
+  },
   "repository": {
     "type": "git",
     "url": "https://github.com/forwardemail/email-templates"