add {{BASEURL}} as replacement pattern (#145)

README.md

@@ -59,7 +59,8 @@ Parameters:
   * `timeout` timeout in [zeit/ms](https://www.npmjs.com/package/ms) format. (e.g. `"2000ms"`, `20s`, `1m`). Default `10s`.
   * `httpHeaders` to apply URL specific headers, see example below.
   * `ignorePatterns` an array of objects holding regular expressions which a link is checked against and skipped for checking in case of a match. Example: `[{ pattern: /foo/ }]`
-  * `replacementPatterns` an array of objects holding regular expressions which are replaced in a link with their corresponding replacement string. This behavior allows (for example) to adapt to certain platform conventions hosting the Markdown. Example: `[{ pattern: /^.attachments/, replacement: "file://some/conventional/folder/.attachments" }]`
+  * `replacementPatterns` an array of objects holding regular expressions which are replaced in a link with their corresponding replacement string. This behavior allows (for example) to adapt to certain platform conventions hosting the Markdown. The special replacement `{{BASEURL}}` can be used to dynamically link to the base folder (used from `projectBaseUrl`) (for example that `/` points to the root of your local repository). Example: `[{ pattern: /^.attachments/, replacement: "file://some/conventional/folder/.attachments" }, { pattern: ^/, replacement: "{{BASEURL}}/"}]`
+  * `projectBaseUrl` the URL to use for `{{BASEURL}}` replacement
   * `ignoreDisable` if this is `true` then disable comments are ignored.
   * `retryOn429` if this is `true` then retry request when response is an HTTP code 429 after the duration indicated by `retry-after` header.
   * `retryCount` the number of retries to be made on a 429 response. Default `2`.
@@ -166,7 +167,7 @@ Options:
 `config.json`:
 
 * `ignorePatterns`: An array of objects holding regular expressions which a link is checked against and skipped for checking in case of a match.
-* `replacementPatterns`: An array of objects holding regular expressions which are replaced in a link with their corresponding replacement string. This behavior allows (for example) to adapt to certain platform conventions hosting the Markdown.
+* `replacementPatterns`: An array of objects holding regular expressions which are replaced in a link with their corresponding replacement string. This behavior allows (for example) to adapt to certain platform conventions hosting the Markdown. The special replacement `{{BASEURL}}` can be used to dynamically link to the current working directory (for example that `/` points to the root of your current working directory).
 * `httpHeaders`: The headers are only applied to links where the link **starts with** one of the supplied URLs in the `urls` section.
 * `timeout` timeout in [zeit/ms](https://www.npmjs.com/package/ms) format. (e.g. `"2000ms"`, `20s`, `1m`). Default `10s`.
 * `retryOn429` if this is `true` then retry request when response is an HTTP code 429 after the duration indicated by `retry-after` header.
@@ -187,6 +188,10 @@ Options:
     {
       "pattern": "^.attachments",
       "replacement": "file://some/conventional/folder/.attachments"
+    },
+    {
+      "pattern": "^/",
+      "replacement": "{{BASEURL}}/"
     }
   ],
   "httpHeaders": [

index.js

@@ -51,7 +51,9 @@ module.exports = function markdownLinkCheck(markdown, opts, callback) {
         if (opts.replacementPatterns) {
             for (let replacementPattern of opts.replacementPatterns) {
                 let pattern = replacementPattern.pattern instanceof RegExp ? replacementPattern.pattern : new RegExp(replacementPattern.pattern);
-                link = link.replace(pattern, replacementPattern.replacement);
+                // replace the `{{BASEURL}}` with the opts.projectBaseUrl. Helpful to build absolute urls "relative" to project roots
+                const replacement = replacementPattern.replacement.replace('{{BASEURL}}', opts.projectBaseUrl);
+                link = link.replace(pattern, replacement);
             }
         }
 

markdown-link-check

@@ -79,6 +79,8 @@ opts.quiet = (program.quiet === true);
 opts.verbose = (program.verbose === true);
 opts.retryOn429 = (program.retry === true);
 opts.aliveStatusCodes = program.alive;
+// set the projectBaseUrl to the current working directory, so that `{{BASEURL}}` can be resolved to the project root.
+opts.projectBaseUrl = `file://${process.cwd()}`;
 
 let markdown = ''; // collect the markdown data, then process it
 

test/local-file.md

@@ -0,0 +1,21 @@
+# Sample
+
+This is a test file leveraging the local replacement patterns `{{BASEURL}}` for `/`:
+
+![img](/test/hello.jpg) (alive)
+![img](%%BASE_URL%%/hello.jpg) (alive)
+![img](hello.jpg) (alive)
+![img](./hello.jpg) (alive)
+![img](/test/goodbye.jpg) (dead)
+![img](/hello.jpg) (dead)
+
+
+
+<!-- markdown-link-check-disable -->
+![img](goodbye.jpg) (dead)
+<!-- markdown-link-check-enable -->
+<!-- markdown-link-check-disable-next-line -->
+![img](goodbye.jpg) (dead)
+![img](goodbye.jpg) (dead) <!-- markdown-link-check-disable-line -->
+<!-- markdown-link-check-disable -->
+![img](goodbye.jpg) (dead)

test/markdown-link-check.test.js

@@ -192,6 +192,31 @@ describe('markdown-link-check', function () {
         });
     });
 
+    it('should check the links in local-file.md', function (done) {
+        markdownLinkCheck(fs.readFileSync(path.join(__dirname, 'local-file.md')).toString().replace(/%%BASE_URL%%/g, 'file://' + __dirname), {baseUrl: 'file://' + __dirname, projectBaseUrl: 'file://' + __dirname + "/..",replacementPatterns: [{ pattern: '^/', replacement: "{{BASEURL}}/"}]}, function (err, results) {
+            expect(err).to.be(null);
+            expect(results).to.be.an('array');
+
+            const expected = [
+                { statusCode: 200, status: 'alive' },
+                { statusCode: 200, status: 'alive' },
+                { statusCode: 200, status: 'alive' },
+                { statusCode: 200, status: 'alive' },
+                { statusCode: 400, status:  'dead' },
+                { statusCode: 400, status:  'dead' },
+            ];
+
+            expect(results.length).to.be(expected.length);
+
+            for (let i = 0; i < results.length; i++) {
+                expect(results[i].statusCode).to.be(expected[i].statusCode);
+                expect(results[i].status).to.be(expected[i].status);
+            }
+
+            done();
+        });
+    });
+
     it('should handle thousands of links (this test takes up to a minute)', function (done) {
         this.timeout(60000);