feat(build): Support for building Java functions using Gradle (aws#1007)

.travis.yml

@@ -1,22 +1,27 @@
 # Enable container based builds
 sudo: required
 language: python
+dist: xenial
 
 services:
   - docker
 
 python:
   - "2.7"
   - "3.6"
+  - "3.7"
 
-# Enable 3.7 without globally enabling sudo and dist: xenial for other build jobs
-matrix:
-  include:
-    - python: 3.7
-      dist: xenial
-      sudo: true
+addons:
+  apt:
+    packages:
+      # Xenial images don't have jdk8 installed by default.
+      - openjdk-8-jdk
 
 before_install:
+  # Use the JDK8 that we installed
+  - JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-amd64
+  - PATH=$JAVA_HOME/bin:$PATH
+
   - nvm install 8.10
   - npm --version
   - node --version

requirements/base.txt

@@ -12,5 +12,5 @@ dateparser~=0.7
 python-dateutil~=2.6
 pathlib2~=2.3.2; python_version<"3.4"
 requests==2.20.1
-aws_lambda_builders==0.0.5
+aws_lambda_builders==0.1.0
 serverlessrepo==0.1.5

samcli/commands/build/command.py

@@ -30,9 +30,10 @@
 \b
 Supported Runtimes
 ------------------
-1. Python2.7\n
-2. Python3.6\n
-3. Python3.7\n
+1. Python 2.7, 3.6, 3.7 using PIP\n
+4. Nodejs 8.10, 6.10 using NPM
+4. Ruby 2.5 using Bundler
+5. Java 8 using Gradle
 \b
 Examples
 --------

samcli/lib/build/app_builder.py

@@ -144,13 +144,33 @@ def update_template(self, template_dict, original_template_path, built_artifacts
         return template_dict
 
     def _build_function(self, function_name, codeuri, runtime):
-        config = get_workflow_config(runtime)
+        """
+        Given the function information, this method will build the Lambda function. Depending on the configuration
+        it will either build the function in process or by spinning up a Docker container.
 
-        # Create the arguments to pass to the builder
+        Parameters
+        ----------
+        function_name : str
+            Name or LogicalId of the function
+
+        codeuri : str
+            Path to where the code lives
+
+        runtime : str
+            AWS Lambda function runtime
 
+        Returns
+        -------
+        str
+            Path to the location where built artifacts are available
+        """
+
+        # Create the arguments to pass to the builder
         # Code is always relative to the given base directory.
         code_dir = str(pathlib.Path(self._base_dir, codeuri).resolve())
 
+        config = get_workflow_config(runtime, code_dir, self._base_dir)
+
         # artifacts directory will be created by the builder
         artifacts_dir = str(pathlib.Path(self._build_dir, function_name))
 
@@ -186,7 +206,8 @@ def _build_function_in_process(self,
                           artifacts_dir,
                           scratch_dir,
                           manifest_path,
-                          runtime=runtime)
+                          runtime=runtime,
+                          executable_search_paths=config.executable_search_paths)
         except LambdaBuilderError as ex:
             raise BuildError(str(ex))
 
@@ -212,7 +233,8 @@ def _build_function_on_container(self,  # pylint: disable=too-many-locals
                                          runtime,
                                          log_level=log_level,
                                          optimizations=None,
-                                         options=None)
+                                         options=None,
+                                         executable_search_paths=config.executable_search_paths)
 
         try:
             try:

samcli/lib/build/workflow_config.py

@@ -2,60 +2,158 @@
 Contains Builder Workflow Configs for different Runtimes
 """
 
+import os
+import logging
 from collections import namedtuple
 
 
-CONFIG = namedtuple('Capability', ["language", "dependency_manager", "application_framework", "manifest_name"])
+LOG = logging.getLogger(__name__)
+
+
+CONFIG = namedtuple('Capability', ["language", "dependency_manager", "application_framework", "manifest_name",
+                                   "executable_search_paths"])
 
 PYTHON_PIP_CONFIG = CONFIG(
                 language="python",
                 dependency_manager="pip",
                 application_framework=None,
-                manifest_name="requirements.txt")
+                manifest_name="requirements.txt",
+                executable_search_paths=None)
 
 NODEJS_NPM_CONFIG = CONFIG(
                 language="nodejs",
                 dependency_manager="npm",
                 application_framework=None,
-                manifest_name="package.json")
+                manifest_name="package.json",
+                executable_search_paths=None)
 
 RUBY_BUNDLER_CONFIG = CONFIG(
                 language="ruby",
                 dependency_manager="bundler",
                 application_framework=None,
-                manifest_name="Gemfile")
+                manifest_name="Gemfile",
+                executable_search_paths=None)
+
+JAVA_GRADLE_CONFIG = CONFIG(
+                language="java",
+                dependency_manager="gradle",
+                application_framework=None,
+                manifest_name="build.gradle",
+                executable_search_paths=None)
 
 
 class UnsupportedRuntimeException(Exception):
     pass
 
 
-def get_workflow_config(runtime):
+def get_workflow_config(runtime, code_dir, project_dir):
     """
-    Get a workflow config that corresponds to the runtime provided
+    Get a workflow config that corresponds to the runtime provided. This method examines contents of the project
+    and code directories to determine the most appropriate workflow for the given runtime. Currently the decision is
+    based on the presence of a supported manifest file. For runtimes that have more than one workflow, we choose a
+    workflow by examining ``code_dir`` followed by ``project_dir`` for presence of a supported manifest.
 
     Parameters
     ----------
     runtime str
         The runtime of the config
 
+    code_dir str
+        Directory where Lambda function code is present
+
+    project_dir str
+        Root of the Serverless application project.
+
     Returns
     -------
     namedtuple(Capability)
         namedtuple that represents the Builder Workflow Config
     """
 
-    workflow_config_by_runtime = {
-        "python2.7": PYTHON_PIP_CONFIG,
-        "python3.6": PYTHON_PIP_CONFIG,
-        "python3.7": PYTHON_PIP_CONFIG,
-        "nodejs4.3": NODEJS_NPM_CONFIG,
-        "nodejs6.10": NODEJS_NPM_CONFIG,
-        "nodejs8.10": NODEJS_NPM_CONFIG,
-        "ruby2.5": RUBY_BUNDLER_CONFIG
+    selectors_by_runtime = {
+        "python2.7": BasicWorkflowSelector(PYTHON_PIP_CONFIG),
+        "python3.6": BasicWorkflowSelector(PYTHON_PIP_CONFIG),
+        "python3.7": BasicWorkflowSelector(PYTHON_PIP_CONFIG),
+        "nodejs4.3": BasicWorkflowSelector(NODEJS_NPM_CONFIG),
+        "nodejs6.10": BasicWorkflowSelector(NODEJS_NPM_CONFIG),
+        "nodejs8.10": BasicWorkflowSelector(NODEJS_NPM_CONFIG),
+        "ruby2.5": BasicWorkflowSelector(RUBY_BUNDLER_CONFIG),
+
+        # When Maven builder exists, add to this list so we can automatically choose a builder based on the supported
+        # manifest
+        "java8": ManifestWorkflowSelector([
+            # Gradle builder needs custom executable paths to find `gradlew` binary
+            JAVA_GRADLE_CONFIG._replace(executable_search_paths=[code_dir, project_dir])
+        ]),
     }
 
-    try:
-        return workflow_config_by_runtime[runtime]
-    except KeyError:
+    if runtime not in selectors_by_runtime:
         raise UnsupportedRuntimeException("'{}' runtime is not supported".format(runtime))
+
+    selector = selectors_by_runtime[runtime]
+
+    try:
+        config = selector.get_config(code_dir, project_dir)
+        return config
+    except ValueError as ex:
+        raise UnsupportedRuntimeException("Unable to find a supported build workflow for runtime '{}'. Reason: {}"
+                                          .format(runtime, str(ex)))
+
+
+class BasicWorkflowSelector(object):
+    """
+    Basic workflow selector that returns the first available configuration in the given list of configurations
+    """
+
+    def __init__(self, configs):
+
+        if not isinstance(configs, list):
+            configs = [configs]
+
+        self.configs = configs
+
+    def get_config(self, code_dir, project_dir):
+        """
+        Returns the first available configuration
+        """
+        return self.configs[0]
+
+
+class ManifestWorkflowSelector(BasicWorkflowSelector):
+    """
+    Selects a workflow by examining the directories for presence of a supported manifest
+    """
+
+    def get_config(self, code_dir, project_dir):
+        """
+        Finds a configuration by looking for a manifest in the given directories.
+
+        Returns
+        -------
+        samcli.lib.build.workflow_config.CONFIG
+            A supported configuration if one is found
+
+        Raises
+        ------
+        ValueError
+            If none of the supported manifests files are found
+        """
+
+        # Search for manifest first in code directory and then in the project directory.
+        # Search order is important here because we want to prefer the manifest present within the code directory over
+        # a manifest present in project directory.
+        search_dirs = [code_dir, project_dir]
+        LOG.debug("Looking for a supported build workflow in following directories: %s", search_dirs)
+
+        for config in self.configs:
+
+            if any([self._has_manifest(config, directory) for directory in search_dirs]):
+                return config
+
+        raise ValueError("None of the supported manifests '{}' were found in the following paths '{}'".format(
+                         [config.manifest_name for config in self.configs],
+                         search_dirs))
+
+    @staticmethod
+    def _has_manifest(config, directory):
+        return os.path.exists(os.path.join(directory, config.manifest_name))

samcli/local/docker/lambda_build_container.py

@@ -35,6 +35,7 @@ def __init__(self,  # pylint: disable=too-many-locals
                  runtime,
                  optimizations=None,
                  options=None,
+                 executable_search_paths=None,
                  log_level=None):
 
         abs_manifest_path = pathlib.Path(manifest_path).resolve()
@@ -53,7 +54,8 @@ def __init__(self,  # pylint: disable=too-many-locals
                                           manifest_file_name,
                                           runtime,
                                           optimizations,
-                                          options)
+                                          options,
+                                          executable_search_paths)
 
         image = LambdaBuildContainer._get_image(runtime)
         entry = LambdaBuildContainer._get_entrypoint(request_json)
@@ -96,7 +98,8 @@ def _make_request(protocol_version,
                       manifest_file_name,
                       runtime,
                       optimizations,
-                      options):
+                      options,
+                      executable_search_paths):
 
         return json.dumps({
             "jsonschema": "2.0",
@@ -119,6 +122,7 @@ def _make_request(protocol_version,
                 "runtime": runtime,
                 "optimizations": optimizations,
                 "options": options,
+                "executable_search_paths": executable_search_paths
             }
         })
 

tests/integration/buildcmd/build_integ_base.py

@@ -1,6 +1,9 @@
 import os
 import shutil
 import tempfile
+import logging
+import subprocess
+import json
 from unittest import TestCase
 
 import docker
@@ -10,10 +13,12 @@
 except ImportError:
     from pathlib2 import Path
 
-
 from samcli.yamlhelper import yaml_parse
 
 
+LOG = logging.getLogger(__name__)
+
+
 class BuildIntegBase(TestCase):
 
     @classmethod
@@ -93,3 +98,15 @@ def _verify_resource_property(self, template_path, logical_id, property, expecte
         with open(template_path, 'r') as fp:
             template_dict = yaml_parse(fp.read())
             self.assertEquals(expected_value, template_dict["Resources"][logical_id]["Properties"][property])
+
+    def _verify_invoke_built_function(self, template_path, function_logical_id, overrides, expected_result):
+        LOG.info("Invoking built function '{}'", function_logical_id)
+
+        cmdlist = [self.cmd, "local", "invoke", function_logical_id, "-t", str(template_path), "--no-event",
+                   "--parameter-overrides", overrides]
+
+        process = subprocess.Popen(cmdlist, stdout=subprocess.PIPE)
+        process.wait()
+
+        process_stdout = b"".join(process.stdout.readlines()).strip().decode('utf-8')
+        self.assertEquals(json.loads(process_stdout), expected_result)