chore: better tags

.drone.yml

@@ -3,8 +3,10 @@ type: docker
 name: default
 
 trigger:
-  branch:
-    - master
+  ref:
+    - refs/heads/master
+    - refs/tags/**
+    - refs/pull/**
 
 steps:
   # Unit Tests
@@ -19,14 +21,26 @@ steps:
     commands:
       - git fetch --tags
 
+  # Compute docker tag: git tag for tag builds, pr-<num> for PRs, dev for master
+  - name: compute tags
+    image: alpine
+    commands:
+      - |
+        if [ "$DRONE_BUILD_EVENT" = "tag" ]; then
+          echo "$DRONE_TAG" > .tags
+        elif [ "$DRONE_BUILD_EVENT" = "pull_request" ]; then
+          echo "pr-$DRONE_PULL_REQUEST" > .tags
+        else
+          echo "dev" > .tags
+        fi
+      - cat .tags
+
   # Publish docker image
   - name: publish docker
     image: plugins/docker
     settings:
       repo: gitea.va.reichard.io/evan/antholume
       registry: gitea.va.reichard.io
-      tags:
-        - dev
       custom_dns:
         - 8.8.8.8
       username: