Task A-2: Storing latest tag in .env file + Read raw .env file

Refer to details in cleanup issue:
Task A-2: e-mission/e-mission-docs#1082 (comment)

Added .env file initialized with the current latest tag of admin-dash and server image.
Internal script can read docker image tags directly from .env.tags using curl to fetch raw file contents.
Storing server tag as well since admin-dash Dockerfile uses it.

Removed workflow dispatch inputs
No longer need inputs since reading from .env.tags in server repo directly

------

Read raw file contents directly instead of using REST API
REST API endpoint returns base64 encoded data which then needs to be decoded.
Can simply read the Raw file contents from the publicly available file.

-----

For now not removing artifacts until the internal script is updated to handle this change.

.env

@@ -1 +1,2 @@
+ADMIN_DASH_IMAGE_TAG=2024-09-20--11-21
 SERVER_IMAGE_TAG=2024-09-20--06-45

.github/workflows/image_build_push.yml

@@ -5,10 +5,6 @@ on:
     branches: [ master ]
 
   workflow_dispatch:
-    inputs:
-      docker_image_tag:
-        description: "Latest Docker image tags passed from e-mission-server repository on image build and push"
-        required: true
 
 env:
   DOCKER_USER: ${{secrets.DOCKER_USER}}
@@ -21,18 +17,24 @@ jobs:
     steps:
     - uses: actions/checkout@v4
 
+    - name: Fetch server image tag
+      id: get-server-tag
+      run: |
+        response=$(curl -s https://raw.githubusercontent.com/MukuFlash03/e-mission-server/refs/heads/cleanup-cicd/.env)
+        SERVER_IMAGE_TAG=$(echo "$response" | grep "SERVER_IMAGE_TAG=" | cut -d'=' -f2)
+        echo "SERVER_IMAGE_TAG=$SERVER_IMAGE_TAG" >> "$GITHUB_OUTPUT"
+
     - name: Set docker image tags
       id: set-tags
       run: |
         set -a; source .env; set +a
-        echo "DOCKER_TAG_FROM_PUSH=${SERVER_IMAGE_TAG}" >> "$GITHUB_OUTPUT"
-        echo "DOCKER_TAG_FROM_WORKFLOW_DISPATCH=${{ github.event.inputs.docker_image_tag }}" >> "$GITHUB_OUTPUT"
+        echo "ADMIN_DASH_IMAGE_TAG=${ADMIN_DASH_IMAGE_TAG}" >> "$GITHUB_OUTPUT"
 
-    - name: Print input docker image tag
+    - name: Print input docker image tags
       run: |
         echo "Event name: ${{ github.event_name }}"
-        echo "Latest docker image tag (push): ${{ steps.set-tags.outputs.DOCKER_TAG_FROM_PUSH }}"
-        echo "Latest docker image tag (workflow_dispatch): ${{ steps.set-tags.outputs.DOCKER_TAG_FROM_WORKFLOW_DISPATCH }}"
+        echo "Current admin-dash image tag (push): ${{ steps.set-tags.outputs.ADMIN_DASH_IMAGE_TAG }}"
+        echo "Latest server image tag (${{ github.event_name }}): ${{ steps.get-server-tag.outputs.SERVER_IMAGE_TAG }}"
 
     - name: docker login
       run: | # log into docker hub account
@@ -47,11 +49,7 @@ jobs:
 
     - name: build docker image
       run: |
-        if [ "${{ github.event_name }}" == "workflow_dispatch" ]; then
-          SERVER_IMAGE_TAG=${{ steps.set-tags.outputs.DOCKER_TAG_FROM_WORKFLOW_DISPATCH }} docker compose -f docker-compose-prod.yml build
-        else
-          SERVER_IMAGE_TAG=${{ steps.set-tags.outputs.DOCKER_TAG_FROM_PUSH }} docker compose -f docker-compose-prod.yml build
-        fi
+        SERVER_IMAGE_TAG=${{ steps.get-server-tag.outputs.SERVER_IMAGE_TAG }} docker compose -f docker-compose-prod.yml build
         docker images
 
     - name: rename docker image
@@ -64,13 +62,9 @@ jobs:
 
     - name: Update .env file 
       run: |
-        if [ "${{ github.event_name }}" == "workflow_dispatch" ]; then
-          echo "Workflow_dispatch: New server image built and pushed, Updating image tag in .env"
-          echo "SERVER_IMAGE_TAG=${{ steps.set-tags.outputs.DOCKER_TAG_FROM_WORKFLOW_DISPATCH }}" > .env
-        else
-          echo "Push event: Restoring latest server image tag from .env"
-        fi
-  
+        echo "ADMIN_DASH_IMAGE_TAG=${{ steps.date.outputs.date }}" > .env
+        echo "SERVER_IMAGE_TAG=${{ steps.get-server-tag.outputs.SERVER_IMAGE_TAG }}" >> .env
+
     - name: Add, Commit, Push changes to .env file
       run: |
         git config --local user.email "[email protected]"
@@ -79,7 +73,7 @@ jobs:
           echo "Latest timestamp already present in .env file, no changes to commit"
         else
           git add .env
-          git commit -m "Updated docker image tag in .env file to the latest timestamp"
+          git commit -m "Updated docker image tags in .env file to the latest timestamp"
           git push origin 
         fi