TiddlyWiki5/editions/tw5.com/tiddlers/webserver/Using the external JavaScript template.tid

created: 20180905075846391
modified: 20210611055708739
tags: [[WebServer Guides]]
title: Using the external JavaScript template
type: text/vnd.tiddlywiki

You can use a special template to externalise TiddlyWiki's core code into a separate file. This configuration allows the browser to cache the core for improved efficiency. 

! Background

TiddlyWiki in the single file configuration ordinarily packs everything into a single file: your data, and the ~JavaScript, CSS and HTML comprising TiddlyWiki itself. This lack of dependencies is usually very convenient: it means that it is impossible for the parts of a TiddlyWiki to become separated, and enormously improves the chances of it still functioning in the future.

However, there is some inefficiency in this arrangement because the core code is repeatedly loaded and saved every time the content of the wiki is saved. This inefficiency is partially ameliorated when working in the client server configuration because once the wiki is loaded by the browser the synchronisation process only transmits individual tiddlers back and forth to the server.

The remaining inefficiency when working in the client server configuration is that the single page wiki that is initially loaded will contain a copy of the entire core code of TiddlyWiki, making it impossible for the browser to cache it.

! Using the external JavaScript template with the client-server configuration

The mechanism is activated by setting the [[root-tiddler|WebServer Parameter: root-tiddler]] parameter to `$:/core/save/all-external-js`. This template externalises TiddlyWiki's core JavaScript into a separate file. For example, the following command will start your server with caching enabled. It will transfer the wiki with two GET requests, and the core can be cached by the browser.

```
tiddlywiki YOUR_WIKI_FOLDER --listen 'root-tiddler=$:/core/save/all-external-js' use-browser-cache=yes
```

<<.tip """You can activate your browser's ''Developer Tools: Network'' tab and reload the page to see how it works.""">>

<<.tip """On Windows, Command Prompt (CMD) users need to replace single quotes `'` with double quotation marks `"`.""">>

!! Initializing a new wiki

The provided edition `server-external-js` contains all the configuration necessary to use the external ~JavaScript template. Here is an example:

```
tiddlywiki ./myNewWiki --init server-external-js
tiddlywiki ./myNewWiki --build listen
```

The above commands perform the following:

* Create a new wiki with external JavaScript customization included.
* Start the server with external JavaScript enabled. The server listens on port 8080. Visit http://localhost:8080 in your browser.

To customize your `--build listen` command, see [[tiddlywiki.info Files]] and [[ListenCommand]].

! Using the external JavaScript template with the single file configuration

You can use the "external-js" template with your single file wiki, but this requires that you have ~TiddlyWiki's core ~JavaScript saved alongside your HTML file. You may prefer this configuration, for example, if you have several wikis on a ~WebDav server. (See: [[Saving via WebDAV]])

<<.warning "This functionality is intended for advanced users: there are many more ways for things to go wrong than with the standard single file configuration">>

!! Saving your snapshots

If you start your ~TiddlyWiki server in the "external-js" configuration, snapshots you save from the wiki will also have the external-js configuration.

You can click on the "cloud" button and choose <<.icon $:/core/images/download-button>>  ''Save snapshot for offline use''. The html wiki you saved will have a reduced file size compared to a regular snapshot because the ~TiddlyWiki core code has been externalized. However, to be able to use this wiki, you ''must'' also have a copy of ~TiddlyWiki's core ~JavaScript in the same directory; see below for instructions for obtaining it

The "server-external-js" edition lets you save the snapshot from the command line:

```
tiddlywiki YOUR_WIKI_FOLDER --build index
```

The files `index.html` and `tiddlywikicore-5.x.x.js` will be saved in your wiki folder's `output` directory.

!! Obtaining the ~TiddlyWiki core in the browser

To download a copy of the TiddlyWiki core JavaScript file from any existing TiddlyWiki, visit the system tiddler $:/core/ui/ExportTiddlyWikiCore and click the download button. (You can search for ''~ExportTiddlyWikiCore'' in the ''Shadows'' tab of $:/AdvancedSearch).

!! Obtaining the ~TiddlyWiki core with Node.js

You can also run the following command to obtain the core ~JavaScript. The file `tiddlywikicore-5.x.x.js` will be saved in the`output` directory of your wiki folder:

```
tiddlywiki YOUR_WIKI_FOLDER \
    --render '$:/core/templates/tiddlywiki5.js' \
    '[[tiddlywikicore-]addsuffix<version>addsuffix[.js]]' \
    'text/plain'
```

The "server-external-js" edition has a shortcut for the BuildCommand to do the same thing:

```
tiddlywiki YOUR_WIKI_FOLDER --build tiddlywikicore
```

! Upgrading your standalone wiki

<<.warning "This procedure is experimental, please take care to backup your data">>

Before you proceed, backup your wiki first! Follow the steps below to upgrade a single-file wiki with the external JavaScript template:

# Proceed with the [[Upgrade Process for Standalone TiddlyWikis|Upgrading]]. Your wiki will be converted to a full standalone HTML.

# Open your upgraded wiki in the browser. If you'd like to revert to using the regular template, restore the original shadow tiddler `$:/config/SaveWikiButton/Template` by deleting any custom copy. Save your wiki and you are done. 

# Otherwise, from your wiki, select the ''Tools'' tab from the sidebar and click on the <<.icon $:/core/images/star-filled>> ''export tiddlywiki core'' button to obtain the core from your wiki.

# Verify that `$:/config/SaveWikiButton/Template` still contains `$:/core/save/offline-external-js`. Modify if necessary.

# Save your wiki again. Your wiki is now converted to using the external core.