Format on Save

An Obsidian plugin that runs any external formatter on save. Bring your own tool — Prettier, deno fmt, or anything else that accepts a file path.

Features

• Format on save — automatically runs your configured formatter on explicit save (Ctrl+S / Cmd+S). Auto-save does not trigger formatting
• Manual command — "Format current file" available from the command palette
• Any formatter — use whatever CLI tool you prefer with its own config files

Configuration

Setting	Description	Default	Example
Enable	Toggle format on explicit save (Ctrl+S / Cmd+S)	true	on/off
Formatter command	Path to the formatter executable	"" (empty)	prettier, deno, /usr/local/bin/prettier
Formatter arguments	Arguments passed before the file path	"" (empty)	--write, fmt

Examples

Prettier:

• Command: prettier
• Arguments: --write

deno fmt:

• Command: deno
• Arguments: fmt

oxfmt:

• Command: oxfmt
• Arguments: --write

The file's absolute path is appended automatically as the last argument.

Place your formatter's config file (.prettierrc, deno.json, .oxfmtrc.json, etc.) in your vault root or home directory as usual.

Release workflow

Releases are fully automated via release-please.

How to release

1. Merge PRs with Conventional Commits into main
2. release-please automatically opens (or updates) a Release PR that bumps the version and updates the changelog
3. Merge the Release PR — this creates a git tag and GitHub Release
4. The publish job builds main.js and uploads release assets

sequenceDiagram
    participant M as main branch
    participant RP as release-please
    participant PB as publish job
    participant GH as GitHub Release

    M->>RP: push with conventional commits
    RP->>M: open/update Release PR (bump version + changelog)
    M->>RP: merge Release PR
    RP->>GH: create git tag + GitHub Release
    GH->>PB: release triggers publish job
    PB->>GH: upload main.js, manifest.json
    PB->>M: commit updated versions.json

Commit conventions

Prefix	Version bump	Example
fix:	patch (0.0.x)	fix: handle empty files on save
feat:	minor (0.x.0)	feat: add timeout setting
feat!: or BREAKING CHANGE:	major (x.0.0)	feat!: change settings format

Release artifacts

Each release includes:

• main.js — bundled plugin code
• manifest.json — plugin metadata

Installation

Manual

1. Build the plugin: pnpm install && pnpm run build
2. Copy main.js and manifest.json to <vault>/.obsidian/plugins/fmt-on-save/
3. Reload Obsidian and enable the plugin in Settings → Community plugins

Desktop only

This plugin uses child_process.exec to run external commands and is desktop only.