feat: initial code for integration testing example

integration_testing/.bazelrc

@@ -0,0 +1 @@
+common --enable_bzlmod

integration_testing/.bazelversion

@@ -0,0 +1 @@
+6.2.0

integration_testing/BUILD.bazel

@@ -0,0 +1,13 @@
+load("@bazel_gazelle//:def.bzl", "gazelle")
+load("@npm//:defs.bzl", "npm_link_all_packages")
+load("@rules_python//python:pip.bzl", "compile_pip_requirements")
+
+compile_pip_requirements(
+    name = "requirements",
+    extra_args = ["--allow-unsafe"],
+)
+
+npm_link_all_packages(name = "node_modules")
+
+# gazelle:prefix github.com/aspect-build/bazel-examples/integration_testing
+gazelle(name = "gazelle")

integration_testing/MODULE.bazel

@@ -0,0 +1,116 @@
+"Declare dependencies for bzlmod, see https://bazel.build/build/bzlmod"
+module(name = "integration_testing_example")
+
+bazel_dep(name = "aspect_bazel_lib",         version = "1.31.2")
+bazel_dep(name = "aspect_rules_js",          version = "1.13.1")
+bazel_dep(name = "aspect_rules_ts",          version = "1.0.5")
+bazel_dep(name = "container_structure_test", version = "1.15.0")
+bazel_dep(name = "gazelle",                  version = "0.28.0", repo_name = "bazel_gazelle")
+bazel_dep(name = "platforms",                version = "0.0.6")
+bazel_dep(name = "protobuf",                 version = "3.19.6")
+bazel_dep(name = "rules_go",                 version = "0.37.0", repo_name = "io_bazel_rules_go")
+bazel_dep(name = "rules_jvm_external",       version = "4.5")
+bazel_dep(name = "rules_oci",                version = "1.0.0-rc0")
+bazel_dep(name = "rules_pkg",                version = "0.9.1")
+bazel_dep(name = "rules_python",             version = "0.21.0")
+
+# Python
+# https://github.com/bazelbuild/rules_python/tree/main/examples/bzlmod
+pip = use_extension("@rules_python//python:extensions.bzl", "pip")
+python = use_extension("@rules_python//python:extensions.bzl", "python")
+
+python.toolchain(
+    name = "python3",
+    python_version = "3.11",
+)
+
+use_repo(python, "python3_toolchains")
+
+register_toolchains(
+    "@python3_toolchains//:all",
+)
+
+pip.parse(
+    name = "pip",
+    requirements_lock = "//:requirements.txt",
+)
+
+use_repo(pip, "pip")
+
+# Java and other JVM languages:
+# https://github.com/bazelbuild/rules_jvm_external/blob/master/examples/bzlmod/MODULE.bazel
+# https://github.com/bazelbuild/rules_jvm_external#pinning-artifacts-and-integration-with-bazels-downloader
+maven = use_extension("@rules_jvm_external//:extensions.bzl", "maven")
+
+maven.install(
+    artifacts = ["io.grpc:grpc-all:1.51.1"],
+    lock_file = "//:maven_install.json",
+)
+
+use_repo(
+    maven,
+    "maven",
+    "unpinned_maven",
+)
+
+# JavaScript and TypeScript
+# https://github.com/aspect-build/rules_js/tree/main/e2e/bzlmod
+# https://github.com/aspect-build/rules_ts/tree/main/e2e/bzlmod
+npm = use_extension("@aspect_rules_js//npm:extensions.bzl", "npm")
+
+npm.npm_translate_lock(
+    name = "npm",
+
+    pnpm_lock = "//:pnpm-lock.yaml",
+    npmrc = "//:.npmrc",
+)
+
+use_repo(npm, "npm")
+
+rules_ts_ext = use_extension(
+    "@aspect_rules_ts//ts:extensions.bzl",
+    "ext",
+    dev_dependency = True,
+)
+
+rules_ts_ext.deps()
+
+use_repo(rules_ts_ext, "npm_typescript")
+
+# Go
+# https://github.com/bazelbuild/rules_go/tree/master/tests/bcr
+go_deps = use_extension("@bazel_gazelle//:extensions.bzl", "go_deps")
+go_sdk = use_extension("@io_bazel_rules_go//go:extensions.bzl", "go_sdk")
+
+go_sdk.download(name = "go_sdk", version = "1.19.3")
+use_repo(go_sdk, "go_sdk")
+
+go_deps.module(
+    path = "google.golang.org/grpc",
+    version = "v1.50.1",
+    sum = "h1:DS/BukOZWp8s6p4Dt/tOaJaTQyPyOoCcrjroHuCeLzY=",
+    build_file_proto_mode = "disable"
+)
+go_deps.module(
+    path = "google.golang.org/protobuf",
+    sum = "h1:d0NfwRgPtno5B1Wa6L2DAG+KivqkdutMf1UhdNx175w=",
+    version = "v1.28.1",
+    build_file_proto_mode = "disable"
+)
+use_repo(go_deps, "org_golang_google_grpc", "org_golang_google_protobuf")
+
+# Docker (OCI) containers
+oci = use_extension("@rules_oci//oci:extensions.bzl", "oci")
+
+oci.pull(
+    name = "distroless_python",
+    #digest = "sha256:b48e216f7c4adcf24fecd7016f3b8ead76866a19571819f67f47c1ccaf899717",
+    image = "gcr.io/distroless/python3",
+    tag = "latest",
+)
+oci.pull(
+    name = "distroless_java",
+    digest = "sha256:161a1d97d592b3f1919801578c3a47c8e932071168a96267698f4b669c24c76d",
+    image = "gcr.io/distroless/java17",
+)
+use_repo(oci, "distroless_python", "distroless_java")

integration_testing/README.md

@@ -0,0 +1,5 @@
+# Integration testing with Bazel
+
+This demonstrates how applications written in several languages can be brought together in a common test fixture, allowing the full stack to be tested at HEAD.
+
+It also shows that the services can be containerized and the containers are managed in the test runner's lifecycle.

integration_testing/WORKSPACE.bazel

@@ -0,0 +1,13 @@
+# Marker that this is the root of a Bazel workspace.
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+# TODO(alex): add this module to registry.bazel.build
+http_archive(
+    name = "aspect_rules_py",
+    sha256 = "c977cadb8703e325f02c1e6a3718e85f52b158e199654b1a28125c420588d720",
+    strip_prefix = "rules_py-0.2.0",
+    url = "https://github.com/aspect-build/rules_py/releases/download/v0.2.0/rules_py-v0.2.0.tar.gz",
+)
+load("@aspect_rules_py//py:repositories.bzl", "rules_py_dependencies")
+rules_py_dependencies()

integration_testing/go.mod

@@ -0,0 +1,16 @@
+module github.com/aspect-build/codelabs
+
+go 1.19
+
+require (
+	google.golang.org/grpc v1.50.1
+	google.golang.org/protobuf v1.28.1
+)
+
+require (
+	github.com/golang/protobuf v1.5.2 // indirect
+	golang.org/x/net v0.0.0-20201021035429-f5854403a974 // indirect
+	golang.org/x/sys v0.1.0 // indirect
+	golang.org/x/text v0.3.3 // indirect
+	google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013 // indirect
+)

integration_testing/go.sum

@@ -0,0 +1,83 @@
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
+github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
+github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.4.0-rc.1/go.mod h1:ceaxUfeHdC40wWswd/P6IGgMaK3YpKi5j83Wpe3EHw8=
+github.com/golang/protobuf v1.4.0-rc.1.0.20200221234624-67d41d38c208/go.mod h1:xKAWHe0F5eneWXFV3EuXVDTCmh+JuBKY0li0aMyXATA=
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+github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
+github.com/golang/protobuf v1.4.1/go.mod h1:U8fpvMrcmy5pZrNK1lt4xCsGvpyWQ/VVv6QDs8UjoX8=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
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integration_testing/java/src/main/java/com/example/BUILD.bazel

@@ -0,0 +1,63 @@
+load("@rules_oci//oci:defs.bzl", "oci_image", "oci_tarball")
+load("@rules_jvm_external//:defs.bzl", "artifact")
+load("@rules_pkg//:pkg.bzl", "pkg_tar")
+
+java_library(
+    name = "logger_java_grpc",
+    srcs = ["LoggerGrpc.java"],
+    deps = [
+        "//schema:logger_java_proto",
+        artifact("com.google.guava:guava"),
+        artifact("com.google.protobuf:protobuf-java"),
+        artifact("io_grpc:grpc-api"),
+        artifact("io_grpc:grpc-core"),
+        artifact("io_grpc:grpc-netty-shaded"),
+        artifact("io_grpc:grpc-protobuf"),
+        artifact("io_grpc:grpc-stub"),
+    ],
+)
+
+java_library(
+    name = "JavaLoggingClientLibrary",
+    srcs = ["JavaLoggingClientLibrary.java"],
+    deps = [
+        ":logger_java_grpc",
+        "//schema:logger_java_proto",
+        artifact("io.grpc:grpc-stub"),
+        artifact("io.grpc:grpc-api"),
+    ],
+)
+
+java_binary(
+    name = "JavaLoggingClient",
+    srcs = ["JavaLoggingClient.java"],
+    visibility = ["//visibility:public"],
+    deps = [":JavaLoggingClientLibrary"],
+)
+
+pkg_tar(
+    name = "tar",
+    srcs = [":JavaLoggingClient"],
+    include_runfiles = True,
+)
+
+oci_image(
+    name = "image",
+    base = "@distroless_java",
+    entrypoint = ["/app"],
+    tars = [":tar"],
+)
+
+# $ bazel build app:tarball
+# $ docker load --input $(bazel cquery --output=files app:tarball)
+# $ docker run --rm gcr.io/example:latest
+#   string(
+# -       "Hello World",
+# +       "Hello Go",
+#   )
+oci_tarball(
+    name = "tarball",
+    image = ":image",
+    repo_tags = ["aspect.build/java-service:latest"],
+    visibility = ["//test:__pkg__"],
+)

integration_testing/java/src/main/java/com/example/JavaLoggingClient.java

@@ -0,0 +1,14 @@
+package com.example;
+
+import java.util.Arrays;
+
+/** A simple client that sends messages to the server to be stored. */
+public class JavaLoggingClient {
+
+  public static void main(String[] args) throws Exception {
+    JavaLoggingClientLibrary client = new JavaLoggingClientLibrary("localhost", 50051);
+    System.out.println("Sending message to server");
+    client.sendLogMessageToServer(Arrays.toString(args));
+    client.shutdown();
+  }
+}

integration_testing/java/src/main/java/com/example/JavaLoggingClientLibrary.java

@@ -0,0 +1,47 @@
+package com.example;
+
+import io.grpc.ManagedChannel;
+import io.grpc.ManagedChannelBuilder;
+import io.grpc.StatusRuntimeException;
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+public class JavaLoggingClientLibrary {
+  private static final Logger logger = Logger.getLogger(JavaLoggingClientLibrary.class.getName());
+
+  private final ManagedChannel channel;
+  private final LoggerGrpc.LoggerBlockingStub blockingStub;
+
+  /** Construct client connecting to server at {@code host:port}. */
+  public JavaLoggingClientLibrary(String host, int port) {
+    this(
+        ManagedChannelBuilder.forAddress(host, port)
+            // Disable TLS to avoid needing certificates.
+            .usePlaintext()
+            .build());
+  }
+
+  /** Construct client for accessing the Logging server using the existing channel. */
+  JavaLoggingClientLibrary(ManagedChannel channel) {
+    this.channel = channel;
+    blockingStub = LoggerGrpc.newBlockingStub(channel);
+  }
+
+  public void shutdown() throws InterruptedException {
+    channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
+  }
+
+  /** Send log message to the server. */
+  public void sendLogMessageToServer(String message) {
+    logger.info("Trying to send message '" + message + "' to server...");
+    LogMessage logMessage = LogMessage.newBuilder().setMessage(message).build();
+    try {
+      blockingStub.sendLogMessage(logMessage);
+    } catch (StatusRuntimeException e) {
+      logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
+      return;
+    }
+  }
+
+}