forked from farhoodlabs/skills
77 lines
2.9 KiB
Markdown
77 lines
2.9 KiB
Markdown
---
|
|
name: github-app-token
|
|
description: Generate a GitHub installation access token from a GitHub App PEM key, App ID, and Installation ID, then authenticate the gh CLI with it.
|
|
---
|
|
|
|
# GitHub App Token Skill
|
|
|
|
Generate a short-lived GitHub installation access token from a GitHub App's credentials and use it to authenticate the `gh` CLI.
|
|
|
|
## Prerequisites
|
|
|
|
The following environment variables MUST be set before invoking this skill:
|
|
|
|
| Variable | Description |
|
|
|---|---|
|
|
| `GITHUB_APP_ID` | The numeric App ID from the GitHub App settings page |
|
|
| `GITHUB_APP_INSTALLATION_ID` | The numeric Installation ID for the target org/user |
|
|
| `GITHUB_APP_PEM_FILE` | Absolute path to the GitHub App's PEM private key file |
|
|
|
|
If any variable is missing, stop and tell the user which ones are required.
|
|
|
|
Requires `openssl`, `curl`, `grep`, and `jq` (standard on modern environments).
|
|
|
|
## Steps
|
|
|
|
### 1. Generate and Export Token
|
|
|
|
Run the helper script and `eval` its output. This securely exports the short-lived GitHub installation access token as `GH_TOKEN` into your current process environment:
|
|
|
|
```bash
|
|
eval "$(/path/to/skills/github-app-token/scripts/generate_token.sh)"
|
|
```
|
|
|
|
> [!NOTE]
|
|
> Because this uses `eval`, the token is scoped only to the current terminal session, process, or script that executes it. For a CI/CD environment (like GitHub Actions), you can extract the token to pass it between steps like so:
|
|
> `echo "GH_TOKEN=$(/path/to/skills/github-app-token/scripts/generate_token.sh | cut -d'"' -f2)" >> $GITHUB_ENV`
|
|
|
|
The script will:
|
|
1. Automatically construct a short-lived authorization assertion using your App ID and PEM key
|
|
2. Call the GitHub API to securely exchange that for an Installation Access Token
|
|
3. Output the `export GH_TOKEN="..."` command to set it in your environment.
|
|
### 2. Authenticate the gh CLI
|
|
|
|
With `GH_TOKEN` set, the `gh` CLI operates securely and without needing a separate authentication login for most API operations. Note that `gh auth status` may not reflect the token since it checks local config, but `gh` will respect the `GH_TOKEN` environment variable!
|
|
|
|
```bash
|
|
# Check that gh is working
|
|
gh api user
|
|
```
|
|
|
|
*(Alternatively, to specifically configure gh auth locally, you can use: `echo "${GH_TOKEN}" | gh auth login --with-token`)*
|
|
|
|
Verify it worked:
|
|
|
|
```bash
|
|
gh auth status
|
|
```
|
|
|
|
You should see authentication via `token` for `github.com`.
|
|
|
|
### 4. Cleanup
|
|
|
|
The installation access token expires after 1 hour. There is nothing to revoke unless you want to explicitly invalidate it early:
|
|
|
|
```bash
|
|
curl -s -X DELETE \
|
|
-H "Authorization: Bearer ${GH_TOKEN}" \
|
|
-H "Accept: application/vnd.github+json" \
|
|
"https://api.github.com/installation/token"
|
|
```
|
|
|
|
## Security Notes
|
|
|
|
- Never log or echo the PEM key or installation token to stdout in production.
|
|
- The installation token represents your GitHub App and is strictly valid for 1 hour from generation.
|
|
- Store the PEM file with restrictive permissions (`chmod 600`) and never check it into git.
|