From b309f2cbc4e5d50804311b7a9ad6e832f42772a4 Mon Sep 17 00:00:00 2001
From: HonkingGoose <34918129+HonkingGoose@users.noreply.github.com>
Date: Tue, 31 Jan 2023 17:34:55 +0100
Subject: [PATCH] docs(dockerfile): explain Docker versioning, improve link
(#20109)
---
lib/modules/manager/dockerfile/readme.md | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/lib/modules/manager/dockerfile/readme.md b/lib/modules/manager/dockerfile/readme.md
index 81a83b76a0..034e0bcba1 100644
--- a/lib/modules/manager/dockerfile/readme.md
+++ b/lib/modules/manager/dockerfile/readme.md
@@ -1,3 +1,22 @@
Extracts all Docker images in a `Dockerfile`.
-If you need to change the versioning format, read the [versioning](https://docs.renovatebot.com/modules/versioning/) documentation to learn more.
+If Renovate does not update your Dockerfile images correctly, you may need to tell Renovate what versioning it should use.
+For example, if you know that an image follows SemVer, you can tell Renovate to use `"semver"` versioning for that image:
+
+```json
+{
+ "packageRules": [
+ {
+ "matchDatasources": ["docker"],
+ "matchPackageNames": ["whitesource/renovate"],
+ "versioning": "semver"
+ }
+ ]
+}
+```
+
+Read [Renovate's Docker Versioning](https://docs.renovatebot.com/modules/versioning/#docker-versioning) docs to learn more.
+
+Renovate's managers does not understand versioning, that's up to Renovate's versioning modules.
+The default Docker versioning for Docker datasources treats suffixes as "compatibility", for example: `-alpine`.
+Many Docker images are _not_ SemVer compliant because they use such suffixes in their tags.
--
GitLab