Plugin REPL

Plugin REPL - In Editor JavaScript Scripting for Automation

readwithai - X -🦋 - blog - machine-aided reading -

Rapidly automate tasks from within notes. Rapidly test and iterate on code for plugins without needing to reload.

Plugin REPL adds an Emacs-like read evaluate print loop (REPL) to Obsidian. This lets you execute JavaScript directly in a document with a single key-press and see the result. It lets you interact with Obsidian's plugin API to make Obsidian do things (move the cursor, insert text, open files, etc). Once you have working code you define new commands directly in JavaScript.

Plugin REPL can be useful when developing plugins or for "light-weight" scripting without having to develop a full plugin.

A range of convenience functions, partly inspired by emacs, is provided to speed up development of straight-forward features.

I am in no way affiliated with Obsidian. This is a third-party plugin.

  Plugin REPL Documentation  

Demo

Installation

Plugin REPL is available from within Obsidian as a community plugin.

Alternatively, you can manually install Plugin REPL:

In your vault, there should be a .obsidian/plugins directory. You can clone this repo into that directory and then run the following to build the plugin:

npm install
npm run dev

You should then be able to enable the plugin in the "Community Plugins" section of Obsidian's settings.

Using

For basic usage, write a JavaScript expression on a line, then run the command "Execute the current line or selection" in the Command Palette. You can also select a region and run this command. I would advise making CTRL-J run this command with a hotkey.

Some other commands are provided. You can find them in the Command Palette by typing "Plugin REPL". These let you to execute a region of JavaScript without inserting the result, or read JavaScript to run from a popup window.

To define a command (run via the Command Palette or a hotkey) use the newCommand function.

The code you write can make use of the convenience functions and variables. This may well provide all the functionality you need for basic scripts, but Plugin REPL also gives you access to much of Obsidian's plugin API through the app, editor and repl (plugin) objects.

The dir and fuzzyDir methods can help explore these objects allong with the API documentation.

If you want functionality, such as defined commands, to rerun each time Obsidian loads you can put this functionality in a repl.md file in your vault.

IMPORTANT LIMITATION. Functions that you define are not shared between different invocations of plugin repl. To share them, you must instead define them as variables like so: var f = function f() {

Documentation

This page provides an overview of functionality. You might like to look at the Obsidian and Plugin Repl Cookbook, which provides various practical examples of how Plugin REPL can be used.

Convenience functions provided

Various convenience functions are provided:

• functions() - List the convenience functions and methods provided

• source(f:string) - Open the markdown file called f and execute the code in it

• command(id:string) - Run a command

• commands() - Return all the ids for commands. You may want to call fuzzySelect(commands())

• newCommand(function name_with_underscores { ...) - Create a new command with name "new name" which runs the function new_name

• dir(o:Object) - List the property in an object

• fuzzyDir(o: Object) - Explore the properties of an object with a fuzzy selector

User interface

• message(s:string) - Print a notification message to the corner of the screen
• popup(s: string) - Popup a dialog displaying a message
• await promptString(prompt: string) - Read a string from a popup
• await fuzzySelect(choices: Array<string>, prompt?: string) - Select from an Array of strings
• openFile(f:string) - Open a file in the current pane
• openUrl(url:string) - Open a url

Settings

• openSetting(name: string) - Open settings and display the tab (see left hand side) with the given name.
• vaultPath is the absolute path of the current vault

Editor commands

• path is the path of the current note

• lineNumber() - return the line number of the current line

• point() - Return the current cursor position

• mark() - Return the cursor position at the beginning of the selection

• pointMin() - Return the minimum cursor in the buffer

• pointMax() - Return the maximun cursor in the buffer

• atEndOfBuffer() - Return true if the cursor is at the end of the buffer.

• jump(p: CursorPoint) - Jump to this point

• forwardChar(count?: number) - Move count (or one) character forward

• endOfLine() - Move to the end of the line

• selection() - Get the text contained in the selection

• bufferString() - Return a string containing the entire text of the buffer

• bufferString(start, end) - Return the string between these two cursor positions (see point() and editor.getCursor())

• insert(s:string) - Insert a string into the buffer

• kill(start?: cursor, end?: cursor) - Delete a region (defaults to the selection)

• await clipboardPut(s: string) - Put a string on the clipboard

• await clipboardGet() - Get the contents of the clipboard

• wordAtPoint(p?:string) - Returns the word at the cursor position. Default to current postion.

• lineAtPoint(p?:string) - Retunrs the line at the cursor position. Default to current positiong.

Reading and files

• await readFile(name: string) - Read the markup file with the title name.
• await writeFile(name: string) - Overwrite the markdown file with the title name with the given string
• await appendToFile(name: string) - Append the given string to the markdown with the title name

Processes

• runProc(s: string) - Parse the bash-style command string s (e.g "ls /home") and call runProc on it
• runProc([command, arg1, arg2, ...]) - Run a command and return what it writes to standard out. Raise and error on error. See require('child_process') for more advanced usage.

Plugins and Modules

• plugin(s:string) - Get the object for a plugin. You may be able to reuse features from another plugin with this.
• plugins() '- Get a list of all the string IDs of plugins used by Obsidian.
• getDv() - Get the dataview object
• replRequire(s: string) - Import the node module installed using Plugin Repl Imports

API access

• repl is the Obsidian plugin object for Plugin REPL. You can use this to define commands and register extensions.
• editor is the Editor object. You can use this to edit to the current note
• app is the global application object.

Defining commands

The function newCommand will create a new command which calls a function. Once you have defined a command, you can define a hotkey to run this command and so call this function.

newCommand(function new_command_name() {
...
})

creates a command with the name "new command name" (and the id new_command_name).

You can use all Plugin REPL's extra functions and variables (app, editor etc) within this function.

If you want to test this funtion by hand, you can do the following:

var f = newCommand(function new_command_name() {
...
})

You can then call f() by executing code to test it.

Running code at startup

If you want code to run at startup, such as for defining commands, then you can place this code in a special file called repl.md. If this file exists, it is read when Obsidian starts (or is reloaded) and the code in it is executed.

Asynchronous code

For convenience, if you call an asynchronous function, Plugin REPL will store the result in the variable _. If there was an error, the error is stored in _error.

Images and Graphs

In order to output images and graphs, you can use code-blocks. These give you access to an el HTML object you can use to store arbitrary HTML. Note that all JavaScript executes in a single global scope by design.

```plugin-repl
el.appendText("hello")
```

Dataview support

The dataview plugin provides functionality to query your obsidian vault. For example, it can return pages or bullet points that match a particular query.

If you have installed the dataview plugin, Plugin REPL gives you access to a dataview object dv which can be used to query all notes.

The following code returns the first list of the page called templates/daily.md.

dv = getDv()
dv.pages().filter((x) => x.file.path == "templates/daily.md")[0].file.lists[0]

Templater support

The Templater library provides functionality to insert templates with some parts of the template derived from JavaScript code. If you have installed Templater, you can use the async templater_expand function to expand template strings.

This creates a command that inserts a files tags using a template:

newCommand(async function templater_example() {
    insert(await templater_expand("The files tags: <% tp.file.tags %>"))
})

If you want to expand a template for a file, you can use readFile:

newCommand(async function templater_from_file() {
    insert(await templater_expand(await readFile("myTemplate")))
})

Importing modules

Modules in Obsidian work in an interesting way that makes installing from NPM a little tricky. There is a technical explanation here.

Plugin REPL has a system to let you import npm modules provided by this repository. To use it, you have to checkout a repository into your vault, update a text file, run a make command and then you can use the replRequire function within Obsidian

Some questions and answers about Plugin REPL

Questions and answers

Alternatives and prior work

• You can use plugins to do the same things that you can do with Plugin REPL but this tends to mean more code.
• js-engine lets you evaulate JavaScript code in code blocks. Execute code gives you code blocks in multiple programming languages. Neither give you access to Obsidian API objects to let you do scripting.
• js-engine lets you evaulate JavaScript code in code blocks. Execute code gives you code blocks in multiple programming languages. Neither give you access to Obsidian api objects to let you do scripting.
• dataview similarly lets you execute JavaScript in code blocks. It gives you access to the app object.
• Templater defines a template language with JavaScript code blocks. It's API gives you access to the app object and people have used "Templates" that when run script Obsidian.
• Obsidian runjs is quite similar in that it allows you to run code from within Obsidian. There is a special syntax for blocks that then show up in a side bar. Plugin REPL is easier to use in my opinion since you can just run code and use the command interface.

Many plugins can create commands at run time from within Obsidian - but they tend to be for more specific uses. I was influenced by obsidian-open-settings for this, as well as for the openSettings command.

Both dataview and Templater implement provide APIs that wrap and simplify aspects of the Obsidian API, Templater's is rather more complete

Attribution

This plugin was based on the Obsidian sample plugin from Obsidian.

It uses the shell-quote library by ljharb and the source code for this is compiled into distribited main.js. This is under an MIT license.

At runtime, it binds against dataview by blacksmith, should you use dataview functionality. This is under an MIT license.

This plugin is highly influenced by Emacs (as are most text editors and a lot of software).

This code exposes and wraps the Obsidian plugin API - as all plugins do - but Plugin REPL does this in a rather more direct / turing-complete way.

About me

I make productivity tools and AI tools related to reading and research.

If that sounds interesting you can follow me on twitter or bluesky. I also write about these topics on substack.

If you find this piece of software useful. Maybe give me money (like $10 dollars?) on my kofi.