Add job to update versions on schedule

.github/workflows/ci.yml

@@ -16,9 +16,14 @@ jobs:
 
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v4
-      - uses: cachix/install-nix-action@v23
-      - uses: cachix/cachix-action@v12
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Check Nix flake inputs
+        uses: DeterminateSystems/flake-checker-action@v4
+      - name: Install Nix
+        uses: DeterminateSystems/nix-installer-action@v6
+      - name: Setup Cachix
+        uses: cachix/cachix-action@v12
         with:
           name: nixpkgs-terraform
           authToken: ${{ secrets.CACHIX_AUTH_TOKEN }}

.github/workflows/update.yaml

@@ -0,0 +1,44 @@
+---
+name: Update versions
+
+on:
+    schedule:
+        - cron: "0 0 * * 0"
+
+concurrency:
+    group: update-versions
+    cancel-in-progress: true
+
+jobs:
+    check:
+        permissions:
+            pull-requests: write
+            contents: write
+        runs-on: ubuntu-latest
+        steps:
+        - name: Checkout
+          uses: actions/checkout@v4
+        - name: Install Nix
+          uses: DeterminateSystems/nix-installer-action@v6
+        - name: Install tools via Nix
+          run: nix develop --impure --check
+        - name: Update versions
+          run: nix develop --impure --command python3 update-versions.py vendor-hash.nix
+          env:
+            GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        - name: Create Pull Request
+          id: create-pull-request
+          uses: peter-evans/create-pull-request@v5
+          with:
+            author: GitHub <[email protected]>
+            commit-message: Update Terraform versions
+            title: Update Terraform versions
+            body: |
+                Automatically created pull-request to update Terraform versions.
+            
+                This is the result of running:
+    
+                ```
+                env GITHUB_TOKEN=<my-token> nix develop --impure --command python3 update-versions.py vendor-hash.nix
+                ```
+            delete-branch: true

README.md

@@ -1,3 +1,4 @@
 # nixpkgs-terraform
+All Terraform versions (>=1.5.0), kept up-to-date on a weekly basis using Nix. Heavily inspired by [cachix/nixpkgs-python](https://github.com/cachix/nixpkgs-python).
 
 [![CI](https://github.com/stackbuilders/nixpkgs-terraform/actions/workflows/ci.yml/badge.svg)](https://github.com/stackbuilders/nixpkgs-terraform/actions/workflows/ci.yml)