ci: Add sync workflow

.github/workflows/envoy-sync.yaml

@@ -0,0 +1,43 @@
+name: Sync Envoy
+
+on:
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+jobs:
+  sync:
+    runs-on: ubuntu-20.04
+    permissions:
+      contents: write
+    if: |
+      ${{
+          !contains(github.actor, '[bot]')
+          || github.actor == 'sync-envoy[bot]'
+      }}
+    steps:
+    # Checkout the repo
+    - name: 'Checkout Repository'
+      uses: actions/checkout@v3
+      with:
+        ref: main
+        fetch-depth: 0
+
+    # Checkout the Envoy repo
+    - name: 'Checkout Repository'
+      uses: actions/checkout@v3
+      with:
+        repository: envoyproxy/envoy
+        ref: main
+        fetch-depth: 0
+        path: upstream
+
+    - run: mv upstream ../envoy
+    - run: ci/sync_envoy.sh
+      env:
+        ENVOY_SRC_DIR: ../envoy

README.md

@@ -8,6 +8,11 @@ This repository contains a Go-based implementation of an API server that
 implements the discovery service APIs defined in
 [data-plane-api](https://github.com/envoyproxy/data-plane-api).
 
+## Proto files
+
+The Go proto files are synced from the upstream Envoy repository (https://github.com/envoyproxy/envoy) on every upstream commit.
+
+Synchronization is triggered using the `envoy-sync.yaml` workflow.
 
 ## Scope
 
@@ -61,8 +66,8 @@ The Envoy xDS APIs follow a well defined [versioning scheme](https://www.envoypr
 
 ### Deprecated
 
-`V2` control-plane code has been removed and will no longer be supported. For previous conversations on support for various xDS versions, see here: 
-- [here](https://docs.google.com/document/d/1ZkHpz6DwEUmAlG0kb2Mgu4iaeQC2Bbb0egMbECoNNKY/edit?ts=5e602993#heading=h.15nsmgmjaaml) 
+`V2` control-plane code has been removed and will no longer be supported. For previous conversations on support for various xDS versions, see here:
+- [here](https://docs.google.com/document/d/1ZkHpz6DwEUmAlG0kb2Mgu4iaeQC2Bbb0egMbECoNNKY/edit?ts=5e602993#heading=h.15nsmgmjaaml)
 - [here](https://envoyproxy.slack.com/archives/C7LDJTM6Z/p1582925082005300)
 
 *Note*: It is recommended to use a previous SHA if there is still a need for `V2`.

ci/sync_envoy.sh

@@ -0,0 +1,96 @@
+#!/bin/bash -eu
+
+set -o pipefail
+
+MIRROR_MSG="Mirrored from envoyproxy/envoy"
+SRCS=(envoy contrib)
+GO_TARGETS=(@envoy_api//...)
+IMPORT_BASE="github.com/envoyproxy/go-control-plane"
+COMMITTER_NAME="envoy-sync[bot]"
+COMMITTER_EMAIL="envoy-sync[bot]@users.noreply.github.com"
+ENVOY_SRC_DIR="${ENVOY_SRC_DIR:-}"
+
+
+if [[ -z "$ENVOY_SRC_DIR" ]]; then
+    echo "ENVOY_SRC_DIR not set, it should point to a cloned Envoy repo" >&2
+    exit 1
+elif [[ ! -d "$ENVOY_SRC_DIR" ]]; then
+    echo "ENVOY_SRC_DIR ($ENVOY_SRC_DIR) not found, did you clone it?" >&2
+    exit 1
+fi
+
+
+build_protos () {
+    # TODO(phlax): use envoy do_ci target once https://github.com/envoyproxy/envoy/pull/27675 lands
+    local go_protos go_proto go_file rule_dir proto input_dir output_dir
+    echo "Building go protos ..."
+    cd "${ENVOY_SRC_DIR}" || exit 1
+
+    # shellcheck disable=SC1091
+    . ci/setup_cache.sh
+
+    read -r -a go_protos <<< "$(bazel query "kind('go_proto_library', ${GO_TARGETS[*]})" | tr '\n' ' ')"
+    bazel build \
+          --experimental_proto_descriptor_sets_include_source_info \
+          "${go_protos[@]}"
+    rm -rf build_go
+    mkdir -p build_go
+    for go_proto in "${go_protos[@]}"; do
+        # strip @envoy_api//
+        rule_dir="$(echo "${go_proto:12}" | cut -d: -f1)"
+        proto="$(echo "${go_proto:12}" | cut -d: -f2)"
+        input_dir="bazel-bin/external/envoy_api/${rule_dir}/${proto}_/${IMPORT_BASE}/${rule_dir}"
+        output_dir="build_go/${rule_dir}"
+        mkdir -p "$output_dir"
+        while read -r go_file; do
+            cp -a "$go_file" "$output_dir"
+        done <<< "$(find "$input_dir" -name "*.go")"
+    done
+    cd - || exit 1
+}
+
+get_last_envoy_sha () {
+    git log \
+        --grep="$MIRROR_MSG" -n 1 \
+        | grep "$MIRROR_MSG" \
+        | tail -n 1 \
+        | sed -e "s#.*$MIRROR_MSG @ ##"
+}
+
+sync_protos () {
+    local src envoy_src
+    echo "Syncing go protos ..."
+    for src in "${SRCS[@]}"; do
+        envoy_src="${ENVOY_SRC_DIR}/build_go/${src}"
+        rm -rf "$src"
+        echo "Copying ${envoy_src} -> ${src}"
+        cp -a "$envoy_src" "$src"
+        git add "$src"
+    done
+}
+
+commit_changes () {
+    local last_envoy_sha changes changed
+    echo "Committing changes ..."
+    changed="$(git diff HEAD --name-only | grep -v envoy/COMMIT || :)"
+    if [[ -z "$changed" ]]; then
+        echo "Nothing changed, not committing"
+        return
+    fi
+    last_envoy_sha="$(get_last_envoy_sha)"
+    changes="$(git -C "${ENVOY_SRC_DIR}" rev-list "${last_envoy_sha}"..HEAD)"
+    echo "Changes detected: "
+    echo "$changes"
+    latest_commit="$(git -C "${ENVOY_SRC_DIR}" rev-list "${last_envoy_sha}"..HEAD | head -n1)"
+    echo "$latest_commit" > envoy/COMMIT
+    git config --global user.email "$COMMITTER_EMAIL"
+    git config --global user.name "$COMMITTER_NAME"
+    git add envoy contrib
+    git commit --allow-empty -s -m "${MIRROR_MSG} @ ${latest_commit}"
+    git push origin main
+}
+
+
+build_protos
+sync_protos
+commit_changes