feat: add parameter to enable setting favicon (#368)

Co-authored-by: Matatjahu <[email protected]>

Author: JarnoRFB

README.md

@@ -18,7 +18,7 @@ HTML template for the [AsyncAPI Generator](https://github.com/asyncapi/generator
 - [Usage](#usage)
 - [Supported parameters](#supported-parameters)
 - [Development](#development)
-- [Contributors ✨](#contributors-%E2%9C%A8)
+- [Contributors ✨](#contributors-)
 
 <!-- tocstop -->
 
@@ -41,10 +41,11 @@ npm install -g @asyncapi/generator
 | sidebarOrganization | Defines how the sidebar should be organized. Set its value to `byTagsNoRoot` to categorize operations by operations tags. Set its value to `byTags` when you have tags on a root level. These tags are used to model tags navigation and need to have the same tags in operations. | No | undefined | `byTags`, `byTagsNoRoot` | `byTagsNoRoot` |
 | baseHref | Sets the base URL for links and forms. | No | `/` | *Any* | `/docs` |
 | version | Override the version of your application provided under `info.version` location in the specification file. | No | Version is taken from the spec file. | *Any* ([See Semver versioning](https://semver.org/)) | `1.0.0` |
-| singleFile | Set output into one html-file with styles and scripts inside | No | `false` | `true`,`false` | `true` |
+| singleFile | Set output into one html-file with styles and scripts inside. | No | `false` | `true`,`false` | `true` |
 | outFilename | The filename of the output file. | No | `index.html` | *Any* | `asyncapi.html` |
-| pdf | Generates output HTML as PDF | No | `false` | `true`, `false` | `true` |
-| pdfTimeout | Timeout (in ms) used to generate the PDF | No | 30000 | >=0 | 1000 |
+| pdf | Generates output HTML as PDF. | No | `false` | `true`, `false` | `true` |
+| pdfTimeout | Timeout (in ms) used to generate the PDF. | No | 30000 | >=0 | 1000 |
+| favicon | Defines the URL/Path used for the favicon. | No | `assets/asyncapi-favicon.ico` | Any valid favicon URL/Path. | `"https://studio.asyncapi.com/favicon.ico"` |
 | config | Inline stringified JSON or a path to a JSON file to override default React component config. The config override is merged with the default config using the [JSON Merge Patch](https://tools.ietf.org/html/rfc7386) algorithm. | No | `{ "show": { "sidebar": true }, "sidebar": { "showOperations": "byDefault" } }` | [JSON config for the React component](https://github.com/asyncapi/asyncapi-react/blob/next/docs/configuration/config-modification.md#definition) | `{"show":{"sidebar":false}}` |
 
 > **NOTE**: If you only generate an HTML website, set the environment variable `PUPPETEER_SKIP_CHROMIUM_DOWNLOAD` to `true` and the generator will skip downloading chromium.

assets/asyncapi-favicon.ico

@@ -2,6 +2,7 @@ const fs = require('fs');
 const path = require('path');
 const React = require('react');
 const ReactDOMServer = require('react-dom/server');
+const fetch = require('node-fetch');
 const { default: AsyncApiComponent, hljs } = require('@asyncapi/react-component');
 const { AsyncAPIDocument } = require('@asyncapi/parser');
 
@@ -92,6 +93,41 @@ function loadLanguagesConfig() {
 }
 filter.loadLanguagesConfig = loadLanguagesConfig;
 
+/**
+ * Generate Base64 value from favicon
+ */
+async function generateBase64Favicon(params, callback) {
+  const favicon = params.favicon;
+
+  // generate Base64 of AsyncAPI logo
+  if (!favicon) {
+    const data = "data:image/x-icon;base64," + fs.readFileSync(path.resolve(__dirname, '../assets/asyncapi-favicon.ico'), "base64");
+    return callback(null, data);
+  }
+
+  try {
+    // Attempt to fetch favicon
+    const response = await fetch(favicon);
+    if (response.status == 200) {
+      const buffer = await response.buffer()
+      const data = "data:image/x-icon;base64," + buffer.toString('base64');
+      callback(null, data);
+    }
+  } catch (fetchErr) {
+    // Failed to fetch favicon...
+    try {
+      // Attempt to read favicon as file
+      const data = "data:image/x-icon;base64," + fs.readFileSync(favicon, "base64");
+      callback(null, data);
+    } catch (err) {
+      console.error("Failed to fetch/read favicon", fetchErr, err);
+      callback(err);
+      throw err;
+    }
+  }
+}
+filter.generateBase64Favicon = generateBase64Favicon;
+
 /**
  * More safe function to include content of given file than default Nunjuck's `include`.
  * Attaches raw file's content instead of executing it - problem with some attached files in template.