Dev or specify image tag (#39)

* default tag to dev for pr merge trigger, but allow user to specify tag on manual run

---------

Signed-off-by: 2byrds <2byrds@gmail.com>

.github/workflows/publish-api.yml

@@ -6,8 +6,7 @@ on:
     branches:
       - "main"
   pull_request:
-    branches:
-      - "main"
+      types: [closed]
   workflow_dispatch:
     inputs:
       version:
@@ -33,12 +32,23 @@ jobs:
         with:
           images: gleif/reg-pilot-api
 
+      - name: Determine Docker tag
+        id: docker_tag
+        run: |
+            if [[ "${{ github.event_name }}" == "pull_request" && "${{ github.event.action }}" == "closed" && "${{ github.event.pull_request.merged }}" == "true" ]]; then
+              echo "::set-output name=tag::dev"
+            elif [[ -n "${{ github.event.inputs.version }}" ]]; then
+              echo "::set-output name=tag::${{ github.event.inputs.version }}"
+            else
+              echo "::set-output name=tag::dev"
+            fi
+  
       - name: Build and push Docker image
         uses: docker/build-push-action@v3
         with:
-          context: .
-          file: images/reg-pilot-api.dockerfile
-          push: true
-          tags: |
-            gleif/reg-pilot-api:${{ github.event.inputs.version }}
-          labels: ${{ github.event.inputs.version }}
+            context: .
+            file: images/reg-pilot-api.dockerfile
+            push: true
+            tags: |
+              gleif/reg-pilot-api:${{ steps.docker_tag.outputs.tag }}
+            labels: ${{ steps.docker_tag.outputs.tag }}