Add render markdown operation

src/core/operations/RenderMarkdown.mjs

@@ -0,0 +1,59 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import MarkdownIt from "markdown-it";
+
+/**
+ * Render Markdown operation
+ */
+class RenderMarkdown extends Operation {
+
+    /**
+     * RenderMarkdown constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Render Markdown";
+        this.module = "Default";
+        this.description = "Renders Markdown as HTML.";
+        this.infoURL = "https://wikipedia.org/wiki/Markdown";
+        this.inputType = "string";
+        this.outputType = "html";
+        this.args = [
+            {
+                name: "Autoconvert URLs to links",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "Convert \\n to <br>",
+                type: "boolean",
+                value: false
+            }
+        ];
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {html}
+     */
+    run(input, args) {
+        const [convertLinks, convertNewLine] = args,
+            md = new MarkdownIt({
+                breaks: convertNewLine,
+                linkify: convertLinks
+            }),
+            rendered = md.render(input);
+
+        return `<div style="font-family: var(--primary-font-family)">${rendered}</div>`;
+    }
+
+}
+
+export default RenderMarkdown;