Add a TIL about downloading assets from a GitHub release

src/_til/2024/2024-11-22-install-from-github-releases.md

@@ -0,0 +1,47 @@
+---
+layout: til
+title: How to install an asset from a GitHub release
+date: 2024-11-22 11:35:50 +0000
+tags:
+  - github
+summary:
+  Use `gh release download`, which includes a pattern matcher if you want to pick a specific asset.
+---
+I wanted to install Caddy in GitHub Actions, and one of the ways [to install it](https://caddyserver.com/docs/install#static-binaries) is by downloading static binaries from their GitHub releases.
+
+I wasn't sure how to download release assets in a sensible way -- I've written shell scripts for it before, but it feels messy and fragile.
+Surely there must be a better way!
+
+I stumbled upon [a GitHub Action](https://github.com/php/php-src/blob/master/.github/actions/setup-caddy/action.yml) in the PHP repository (!) which pointed me in the right direction:
+
+```shell
+gh release -R caddyserver/caddy download --pattern 'caddy_*_linux_amd64.tar.gz' -O - | sudo tar -xz -C /usr/bin caddy
+sudo chmod +x /usr/bin/caddy
+```
+
+This is using [the GitHub CLI](https://cli.github.com/), which I haven't used before -- but it's pre-installed in GitHub Actions, which is very convenient for my purposes!
+
+## In a GitHub Action
+
+Here's how I packaged this as a step in a GitHub Action:
+
+```yml
+- name: Install Caddy
+  env:
+    GH_TOKEN: ${{ github.token }}
+  run: |
+    gh release download \
+      --repo caddyserver/caddy \
+      --pattern 'caddy_*_linux_amd64.tar.gz' \
+      --output caddy.tar.gz
+    tar -xzf caddy.tar.gz --directory /usr/local/bin
+    chmod +x /usr/local/bin/caddy
+    which caddy
+```
+
+It's a bit more verbose and leaves a `caddy.tar.gz` file lying around, but I find this version easier to understand and debug.
+
+## Notes
+
+*   You can specific a release to `gh release download`, or if not it will pick the latest release.
+    If you let it pick automatically, it skips pre-releases.