feat(install): support a custom INSTALL_DIR

[arlenvasconcelos]

Description

The quick-install script hardcoded /usr/local/bin, which forces sudo on machines where the user has a perfectly good ~/.local/bin. INSTALL_DIR now overrides it, the directory is created when missing, and the success message names where the binary landed plus a note when that path is not on PATH.

Relative paths are rejected up front: the script cds into the temp dir it extracts to and then deletes, so a relative INSTALL_DIR would install into that dir and vanish.

Default behaviour is unchanged — with no INSTALL_DIR set, the install still goes to /usr/local/bin and still escalates to sudo when that directory isn't writable.

curl -fsSL https://get.radarhq.io | INSTALL_DIR="$HOME/.local/bin" sh

Files touched:

• install.sh — INSTALL_DIR env override, absolute-path guard, mkdir -p (via sudo when needed), install path in the success message, PATH membership note
• .github/workflows/installers.yml — two smoke steps covering the new behaviour
• README.md — documents the custom install location

Type of change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

How has this been tested?

Installer-only change — it never touches a cluster, so the minikube/remote-cluster boxes don't apply.

• sh -n install.sh — POSIX sh syntax check passes.

• The install block (mkdir / -w / $SUDO / PATH check) was exercised directly in a scratch directory: writable custom dir, missing custom dir that gets created, and a relative INSTALL_DIR, which exits 1 before any download or extract.

• Two new CI steps in installers.yml run the real script end to end on the ubuntu and macOS runners:

  • custom absolute INSTALL_DIR → asserts both kubectl-radar --version and radar --version from that directory
  • relative INSTALL_DIR → asserts the install fails

• The workflow's existing shellcheck --shell=sh install.sh step is the lint gate for the new code; it was not run locally (shellcheck isn't installed on this machine).

• The existing default-path step (sh ./install.sh → /usr/local/bin/kubectl-radar --version) is unchanged and still passes, which is the regression guard on the default.

• Tested locally with minikube/kind

• Tested against a remote cluster

• Added/updated unit tests

Checklist

• My code follows the project's coding standards
• I have performed a self-review of my code
• I have added comments where necessary
• My changes generate no new warnings
• Any dependent changes have been merged

Related issues

Fixes #1563

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Note

Low Risk
Installer-only change with default behavior preserved; risk is limited to where binaries are placed on the user’s machine, with guards against relative paths and invalid targets.

Overview
The macOS/Linux quick-install script now accepts INSTALL_DIR to override the default /usr/local/bin, so users can install into writable paths like ~/.local/bin without sudo. Relative paths are rejected before download/extract (they would land in the temp dir that gets deleted), and an existing non-directory path fails fast.

Install flow creates the target directory when missing (mkdir -p, with sudo when the dir isn’t writable), consolidates the binary move behind $SUDO, and improves post-install messaging: success names the install path and warns when that path isn’t on PATH.

README documents the custom-location one-liner; CI adds smoke tests for a custom absolute INSTALL_DIR and for a relative path that must fail without creating directories.

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