use tags parsing for basis of deployed docs versions

docs/website/tools/update_versions.js

@@ -1,5 +1,7 @@
 const proc = require('child_process')
 const fs = require('fs');
+const semver = require('semver')
+
 
 // const
 REPO_DIR = ".dlt-repo"
@@ -8,11 +10,41 @@ REPO_URL = "https://github.com/dlt-hub/dlt.git"
 VERSIONED_DOCS_FOLDER = "versioned_docs"
 VERSIONED_SIDEBARS_FOLDER = "versioned_sidebars"
 
-// TODO: get tags automatically, put newest version on top
-const VERSIONS = [
-    "0.5.4",
-    "0.4.12",
-]
+// no doc versions below this version will be deployed
+MINIMUM_SEMVER_VERSION = "0.4.0"
+
+// find tags
+console.log("Discovering versions")
+const tags = proc.execSync(`git tag`).toString().trim().split("\n");
+console.log(`Found ${tags.length} tags`)
+
+// parse and filter invalid tags
+let versions = tags.map(v => semver.valid(v)).filter(v => v != null)
+
+// remove all tags below the min version and sort
+min_version = semver.valid(MINIMUM_SEMVER_VERSION)
+versions = semver.rsort(versions.filter(v => semver.gt(v, min_version)))
+
+// remove prelease versions
+versions.filter(v => semver.prerelease(v) == null)
+
+console.log(`Found ${versions.length} elligible versions`)
+if (versions.length < 5) {
+    console.error("Sanity check failed, not enough elligble version tags found")
+    process.exit(1)
+}
+
+// go through the versions and find all newest versions of minor versions
+const selectedVersions = [versions[0]];
+let lastVersion = versions[0];
+for (let ver of versions) {
+    if (semver.minor(ver) != semver.minor(lastVersion) || semver.major(ver) != semver.major(lastVersion)) {
+        selectedVersions.push(ver)
+    }
+    lastVersion = ver;
+}
+
+console.log(`Will create docs versions for ${selectedVersions}`)
 
 // create folders
 fs.rmSync(VERSIONED_DOCS_FOLDER, { recursive: true, force: true })
@@ -35,19 +67,19 @@ const branch = proc.execSync(`cd ${REPO_DIR} && git rev-parse --abbrev-ref HEAD`
 
 if (branch != "devel") {
     console.error("Could not check out devel branch")
-    process.exit()
+    process.exit(1)
 }
 
-VERSIONS.reverse()
-for (const version of VERSIONS) {
+selectedVersions.reverse()
+for (const version of selectedVersions) {
 
     // checkout verison and verify we have the right tag
     console.log(`Generating version ${version}, switching to tag:`)
     proc.execSync(`cd ${REPO_DIR} && git checkout ${version}`)
     const tag = proc.execSync(`cd ${REPO_DIR} && git describe --exact-match --tags`).toString().trim()
     if (tag != version) {
         console.error(`Could not checkout version ${version}`)
-        process.exit()
+        process.exit(1)
     }
 
     // build doc version, we also run preprocessing and markdown gen for each doc version