Added handling for invalid redirect regexes

refs https://linear.app/tryghost/issue/CORE-84/have-a-look-at-the-eggs-redirects-refactor-branch
refs 8f5186995d
refs 260a47da83

- The router should not stop working when an invalid redirect definition is added
- Referenced commits solve this exact problem before this module was introduced

ghost/express-dynamic-redirects/lib/DynamicRedirectManager.js

@@ -92,19 +92,27 @@ class DynamicRedirectManager {
      * @returns {string} The redirect ID
      */
     addRedirect(from, to, options) {
-        const fromRegex = this.buildRegex(from);
-        const redirectId = from;
+        try {
+            const fromRegex = this.buildRegex(from);
+            const redirectId = from;
 
-        this.redirectIds.push(redirectId);
-        this.redirects[redirectId] = {
-            fromRegex,
-            to,
-            options
-        };
+            this.redirectIds.push(redirectId);
+            this.redirects[redirectId] = {
+                fromRegex,
+                to,
+                options
+            };
 
-        this.setupRedirect(redirectId);
+            this.setupRedirect(redirectId);
 
-        return redirectId;
+            return redirectId;
+        } catch (error) {
+            if (error.message.match(/Invalid regular expression/gi)) {
+                return null;
+            }
+
+            throw error;
+        }
     }
 
     /**

ghost/express-dynamic-redirects/test/DynamicRedirectManager.test.js

@@ -76,4 +76,41 @@ describe('DynamicRedirectManager', function () {
         should.equal(status, null);
         should.equal(location, null);
     });
+
+    it('The routing works when passed an invalid regexp for the from parameter', function () {
+        const manager = new DynamicRedirectManager({permanentMaxAge: 100, urlUtils});
+
+        const from = '/invalid_regex/(/size/[a-zA-Z0-9_-.]*/[a-zA-Z0-9_-.]*/[0-9]*/[0-9]*/)([a-zA-Z0-9_-.]*)';
+        const to = '/';
+
+        manager.addRedirect(from , to, {
+            permanent: false
+        });
+
+        const req = {
+            method: 'GET',
+            url: '/test-params/'
+        };
+
+        let headers = null;
+        let status = null;
+        let location = null;
+        const res = {
+            set(_headers) {
+                headers = _headers;
+            },
+            redirect(_status, _location) {
+                status = _status;
+                location = _location;
+            }
+        };
+
+        manager.handleRequest(req, res, function next() {
+            should.ok(true, 'next should have been called');
+        });
+
+        should.equal(headers, null);
+        should.equal(status, null);
+        should.equal(location, null);
+    });
 });