Deno wrapper

🦕 Like ./gradlew, but for Deno

🦕 Downloads a pinned version of Deno
📂 Caches Deno installation in the .deno folder
🌟 Works best when placed at the root of your project as ./denow
👤 Users don’t need to install deno globally

Installation

Find your existing Deno project, then run one of these commands:

curl -fsSL https://deno.land/x/deno_wrapper/deno_wrapper.sh | sh

irm https://deno.land/x/deno_wrapper/deno_wrapper.ps1 | iex

You can add a vN.N.N argument to download a specific version. By default we use the Deno.version.deno version.

curl -fsSL https://deno.land/x/deno_wrapper/deno_wrapper.sh | sh -s 1.30.0

⚠️ For PowerShell, you’ll need to use a named variable $v since iex doesn’t accept extra CLI arguments.

$v="1.30.0"; irm https://deno.land/x/deno_wrapper/deno_wrapper.ps1 | iex

This CLI will create the wrapper scripts as ./denow for POSIX and ./denow.bat for Windows. ⚠️ The windows script is a convenience wrapper that delegates to the POSIX shell script using Git Bash as the shell.

Usage

Just use ./denow as though it were the true deno binary! Anyone who clones your repo won’t need to install deno themselves; the ./denow will auto-install a local copy into the .deno folder.

⚠️ Make sure you add .deno to your .gitignore! That’s where deno will be installed to by the wrapper.

./denow --help
./denow eval 'console.log(42)'
./denow fmt
./denow task mytask
./denow compile --allow-read --allow-net https://deno.land/std/http/file_server.ts
./denow run --allow-net https://examples.deno.land/http-server.ts
./denow run -A src/index.ts

If you want to update the version of Deno that ./denow downloads and invokes, you can go through the install steps (above) again to pin to a different version. Be aware that this will overwrite the ./denow and ./denow.bat files. You can also inspect the generated ./deno and ./deno.bat files to see what version of Deno they are invoking and change it manually.

Why?

Sometimes (not often, but sometimes), you want to have an auto-install wrapper around a project-critical binary. In a nutshell you gain the following benefits:

Standardizes a project on a given Deno version, leading to more reliable and robust builds.
Provisioning a new Deno version to different users and execution environment (e.g. IDEs or Continuous Integration servers) is as simple as changing the Wrapper definition.

For instance, GitHub Actions can be written using Deno, but how do you make sure deno is available on the GitHub Action runner? You can use ./denow (or ./denow.bat) as a proxy!

Why not just download the `deno` binary as `./deno`?

Because the Deno binary is >100MB, which is more than most version control systems want to deal with. GitHub will even block files larger than 100MB!

Development

The main denow script is written in POSIX shell code. That means things like [[ $hello == world ]] are off the table. Only POSIX-compatible things are allowed. The deno_wrapper.sh script is also POSIX-compatible since it’s supposed to be as easy to run as possible.