Initial checkin

Based on a PoC done in phly/keep-a-changelog.

Signed-off-by: Matthew Weier O'Phinney <[email protected]>

.github/actions/generate-tags/action.yml

@@ -0,0 +1,11 @@
+name: 'Create major/minor tags'
+description: 'Create a list of major and minor versions to tag from the current tag.'
+outputs:
+  original-tag:
+    description: 'Original tag name'
+  tags:
+    description: 'Multiline string with tag names to create, one per line.'
+
+runs:
+  using: 'node12'
+  main: 'index.js'

.github/actions/generate-tags/index.js

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+const core = require('@actions/core');
+const semver = require('semver')
+
+let tagRef = core.getInput('tag-ref');
+let tag    = tagRef.split('/').pop();
+
+let major = semver.major(tag);
+let minor = major + '.' + semver.minor(tag);
+
+let tags = [
+    'v' + major,
+    'v' + minor,
+];
+
+core.info(`Tags: ${JSON.stringify(tags)}`);
+core.setOutput('tags', tags.join("\n"));