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Deno 2 is finally here 🎉️
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Deno wrapper

🦕 Like ./gradlew, but for Deno

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

🦕 Downloads a pinned version of Deno
📂 Caches Deno installation in the .deno folder
🌟 Creates a ./denow wrapper script that auto-downloads Deno
👤 Users don’t need to install deno globally

Installation

curl sh PowerShell

curl -fsSL https://deno.land/x/denow/install.sh | sh
irm https://deno.land/x/denow/install.ps1 | iex

If you want to install a specific version of Deno instead of the latest version you can use an extra argument to choose a specific version. This is the version (1.38.0), not the tag name (v1.38.0).

curl -fsSL https://deno.land/x/denow/install.sh | sh -s 1.38.0
v="1.38.0"; irm https://deno.land/x/denow/install.ps1 | iex

🛑 If you’re looking to install Deno globally check out the Deno website for an installation guide.

Usage

Terminal Linux macOS Windows

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 file. You can also inspect the generated ./denow file to see what version of Deno they are invoking and change it manually.

Why?

💡 Inspired by The Gradle Wrapper

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 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

Bash sh cmd

Make sure that any changes are roughly the same in the ./denow.bat and ./deno wrappers as well as the install.ps1 and install.sh installers.