Merge pull request #5 from Scalingo/feat/registry_upstreams

feat(openresty): allow to setup upstreams for load balancing on reads

Author: mickael-garrido

.github/workflows/docker-image.yml

@@ -0,0 +1,33 @@
+name: CI
+
+on:
+  push:
+    tags:
+      - 'v(\.?[0-9]+){3}(-[a-z0-9]+)?'
+
+jobs:
+  bake:
+    name: Build and Push the Docker image
+    runs-on: ubuntu-22.04
+    env:
+      image_name: docker-registry-proxy-cache
+      org_name: scalingo
+    steps:
+      # Docker login
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ vars.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKER_TOKEN }}
+
+      # Set docker buildx environment
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      # Build and push with bake
+      - name: Build and push
+        uses: docker/bake-action@v6
+        with:
+          push: true
+          set: |
+            ${{ env.image_name }}.tags=[${{ env.org_name }}/${{ env.image_name }}:${{ github.ref_name }}]

entrypoint.sh

@@ -143,6 +143,9 @@ echo -e "\nManifest caching config: ---\n"
 cat /opt/openresty/nginx/conf/nginx.manifest.caching.config.conf
 echo "---"
 
+# Upstreams configuration. We generate config based on the environment vars.
+echo -n "" >/opt/openresty/nginx/conf/upstreams.conf
+
 if [[ "a${ALLOW_PUSH}" == "atrue" ]]; then
   cat <<EOF >/opt/openresty/nginx/conf/allowed.methods.conf
     # allow to upload big layers
@@ -164,6 +167,37 @@ else
         return 405  "DELETE method is not allowed";
     }
 EOF
+  if [ "$UPSTREAM_REGISTRIES" ]; then
+    UPSTREAM_REGISTRIES_DELIMITER=${UPSTREAM_REGISTRIES_DELIMITER:-" "}
+    s=$UPSTREAM_REGISTRIES$UPSTREAM_REGISTRIES_DELIMITER
+    upstream_array=()
+    while [[ $s ]]; do
+      upstream_array+=("${s%%"$UPSTREAM_REGISTRIES_DELIMITER"*}")
+      s=${s#*"$UPSTREAM_REGISTRIES_DELIMITER"}
+    done
+
+    UPSTREAM_REGISTRY_DELIMITER=${UPSTREAM_REGISTRY_DELIMITER:-"|"}
+
+    for ONEREGISTRY in "${upstream_array[@]}"; do
+      s=$ONEREGISTRY$UPSTREAM_REGISTRY_DELIMITER
+      registry_array=()
+      while [[ $s ]]; do
+        registry_array+=("${s%%"$UPSTREAM_REGISTRY_DELIMITER"*}")
+        s=${s#*"$UPSTREAM_REGISTRY_DELIMITER"}
+      done
+      cat <<-EOF >>/opt/openresty/nginx/conf/upstreams.conf
+upstream ${registry_array[0]} {
+$(
+        for i in ${!registry_array[@]}; do
+          if [[ i -gt 0 ]]; then
+            echo "    server ${registry_array[$i]} fail_timeout=5;"
+          fi
+        done
+      )
+}
+EOF
+    done
+  fi
 fi
 
 # Only configure htpasswd if the env var exists

nginx.conf

@@ -81,6 +81,9 @@ http {
     # Entrypoint generates the proxy_cache_path here, so it is configurable externally.
     include /opt/openresty/nginx/conf/cache_max_size.conf;
 
+    # Entrypoint generates the upstreams here, so it is configurable externally.
+    include /opt/openresty/nginx/conf/upstreams.conf;
+
     # Just in case you want to rewrite some hosts. Default maps directly.
     map $host $targetHost {
         hostnames;