Test that canton 3.x builds with bazel hourly (#17876)

* introduce a canton2 directory

* rename to canton-3x and only keep the bazel rules

* add canton-3x to bazelignore

* fix visibility rules

* add a build-canton-3x script

* add build-canton-3x.sh temporarily to prs.yml to test it out

* try sending a message to stack when failing

* backport 243125adee

* restore prs.yml and add the job to azure-cron.yml

* restore tell-slack-failed condition

* address comments

* display the revision at which canton was cloned, to ease debugging

.bazelignore

@@ -7,3 +7,4 @@ language-support/ts/node_modules/
 language-support/ts/packages/node_modules/
 navigator/frontend/node_modules/
 compatibility/
+canton-3x/

.pre-commit-config.yaml

@@ -4,7 +4,7 @@
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
 
-exclude: '^canton/'
+exclude: '^canton(-3x)?/'
 repos:
 - repo: local
   hooks:

.prettierignore

@@ -27,3 +27,4 @@ navigator/frontend/src/ui-core/src/api/Queries.ts
 
 # ignore canton code drop
 canton
+canton-3x

.scalafmt.conf

@@ -16,5 +16,7 @@ newlines.topLevelStatementBlankLines = [
 # to not get more than we want.
 project.excludePaths = [
   "glob:**/canton/community/**/*.{scala,sc}",
-  "glob:**/canton/daml-common-staging/**/*.{scala,sc}"
+  "glob:**/canton/daml-common-staging/**/*.{scala,sc}",
+  "glob:**/canton-3x/community/**/*.{scala,sc}",
+  "glob:**/canton-3x/daml-common-staging/**/*.{scala,sc}"
 ]

azure-cron.yml

@@ -211,3 +211,15 @@ jobs:
       - template: ci/tell-slack-failed.yml
 
   - template: ci/refresh-get-daml-com.yml
+
+  - job: build_canton_3x_with_bazel
+    timeoutInMinutes: 120
+    pool:
+      name: 'ubuntu_20_04'
+      demands: assignment -equals default
+    steps:
+      - checkout: self
+      - bash: ci/build-canton-3x.sh
+        env:
+          GITHUB_TOKEN: $(CANTON_READONLY_TOKEN)
+      - template: ci/tell-slack-failed.yml

canton-3x/shade_rule

@@ -0,0 +1 @@
+zap org.apache.pekko.stream.scaladsl.BroadcastHub*

ci/build-canton-3x.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+# Copyright (c) 2023 Digital Asset (Switzerland) GmbH and/or its affiliates. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+set -euo pipefail
+
+eval "$(./dev-env/bin/dade-assist)"
+
+tmp=$(mktemp -d)
+trap 'rm -rf ${tmp}' EXIT
+
+if [ -z "${GITHUB_TOKEN:-}" ]; then
+  repo_url="git@github.com:DACH-NY/canton.git"
+else
+  repo_url="https://$GITHUB_TOKEN@github.com/DACH-NY/canton"
+fi
+
+git clone --depth 1 --branch main $repo_url $tmp
+head=$(git -C $tmp rev-parse HEAD)
+echo "cloned at revision $head"
+
+for path in community daml-common-staging; do
+  src=$tmp/$path
+  dst=canton-3x/$path
+  rm -rf $dst
+  mkdir -p $(dirname $dst)
+  cp -rf $src $dst
+  git add $dst
+done
+
+sed -i 's/canton-3x\///' .bazelignore
+bazel build //canton-3x/...

ci/tell-slack-failed.yml

@@ -23,6 +23,7 @@ steps:
            -H 'Content-type: application/json' \
            --data "{\"text\":\"$WARNING\n\"}" \
            $(Slack.ci-failures-daml)
+    name: tell_slack_failed
     condition: and(failed(),
                    or(eq(variables['Build.SourceBranchName'], 'main'),
                       startsWith(variables['Build.SourceBranch'], 'refs/heads/release/')))

daml-lf/api-type-signature/BUILD.bazel

@@ -29,6 +29,7 @@ da_scala_library(
     tags = ["maven_coordinates=com.daml:daml-lf-api-type-signature:__VERSION__"],
     visibility = [
         "//canton:__subpackages__",
+        "//canton-3x:__subpackages__",
         "//daml-assistant/daml-sdk:__subpackages__",
         "//daml-lf:__subpackages__",
         "//daml-script:__subpackages__",

daml-lf/interpreter/BUILD.bazel

@@ -29,6 +29,7 @@ da_scala_library(
     tags = ["maven_coordinates=com.daml:daml-lf-interpreter:__VERSION__"],
     visibility = [
         "//canton:__subpackages__",
+        "//canton-3x:__subpackages__",
         "//compiler/repl-service:__subpackages__",
         "//compiler/scenario-service:__subpackages__",
         "//daml-lf:__subpackages__",

daml-lf/validation/BUILD.bazel

@@ -21,6 +21,7 @@ da_scala_library(
     tags = ["maven_coordinates=com.daml:daml-lf-validation:__VERSION__"],
     visibility = [
         "//canton:__subpackages__",
+        "//canton-3x:__subpackages__",
         "//compiler/scenario-service:__subpackages__",
         "//daml-lf:__subpackages__",
         # TODO https://github.com/digital-asset/daml/issues/15453

fmt.sh

@@ -49,7 +49,7 @@ check_diff() {
   # $1 merge_base
   # $2 regex
   # "${@:3}" command
-  changed_files=$(git diff --name-only --diff-filter=ACMRT "$1" | grep $2 | grep -v '^canton/' || [[ $? == 1 ]])
+  changed_files=$(git diff --name-only --diff-filter=ACMRT "$1" | grep $2 | grep -E -v '^canton(-3x)?/' || [[ $? == 1 ]])
   if [[ -n "$changed_files" ]]; then
     run "${@:3}" ${changed_files[@]:-}
   else
@@ -147,7 +147,7 @@ if [ "$diff_mode" = "true" ]; then
   check_diff $merge_base '\.\(ts\|tsx\)$' run_pprettier ${prettier_args[@]:-}
 else
   run hlint -j4 --git
-  java_files=$(find . -name "*.java" | grep -v '^\./canton')
+  java_files=$(find . -name "*.java" | grep -E -v '^\./canton(-3x)?')
   if [[ -z "$java_files" ]]; then
     echo "Unexpected: no Java file in the repository"
     exit 1