Add GH action to update sha256sums

/cc @bryceml

.github/workflows/checksums.yml

@@ -0,0 +1,49 @@
+name: Checksums
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  checksums:
+    name: Update Release Checksums
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          ref: stable
+
+      - name: Get bootstrap-salt.sh sha256sum
+        run: |
+          echo "SH=$(sha256sum bootstrap-salt.sh | awk '{ print $1 }')" >> $GITHUB_ENV
+          echo "PS1=$(sha256sum bootstrap-salt.ps1 | awk '{ print $1 }')" >> $GITHUB_ENV
+          echo "BS_VERSION=$(sh bootstrap-salt.sh -v | awk '{ print $4 }')" >> $GITHUB_ENV
+
+      - name: Set up Python 3.7
+        uses: actions/setup-python@v1
+        with:
+          python-version: 3.7
+
+      - name: Update Checksums
+        run: |
+          echo ${{ env.SH }} > bootstrap-salt.sh.sha256
+          echo ${{ env.PS1 }} > bootstrap-salt.ps1.sha256
+          git config --global user.name 'SaltStack GH Automation'
+          git config --global user.email 'actions@github.com'
+          git add *.sha256
+          git commit -am "Update sha256 checksums"
+          git push
+
+      - uses: actions/checkout@v2
+        with:
+          ref: develop
+
+      - name: Update Latest Release on README
+        run: |
+          python3 .github/workflows/scripts/update-release-shasum.py ${{ env.BS_VERSION }} ${{ env.SH }}
+          git config --global user.name 'SaltStack GH Automation'
+          git config --global user.email 'actions@github.com'
+          git commit -am "Update README.rst with latest release sha256sum"
+          git push

.github/workflows/scripts/update-release-shasum.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python
+import sys
+import pathlib
+
+THIS_FILE = pathlib.Path(__file__).resolve()
+CODE_ROOT = THIS_FILE.parent.parent.parent.parent
+README_PATH = CODE_ROOT / "README.rst"
+
+
+def main(version, sha256sum):
+    in_contents = README_PATH.read_text()
+    out_contents = ""
+    found_anchor = False
+    updated_version = False
+    if version not in in_contents:
+        for line in in_contents.splitlines(True):
+            if updated_version:
+                out_contents += line
+                continue
+            if found_anchor:
+                if not line.startswith("-"):
+                    out_contents += line
+                    continue
+                out_contents += "- {}: ``{}``\n".format(version, sha256sum)
+                out_contents += line
+                updated_version = True
+                continue
+
+            out_contents += line
+            if line.startswith(".. _sha256sums:"):
+                found_anchor = True
+    if in_contents != out_contents:
+        README_PATH.write_text(out_contents)
+
+
+if __name__ == '__main__':
+    main(sys.argv[1], sys.argv[2])