src(buildpack): add python

Makefile

@@ -12,12 +12,14 @@ GO_BUILDER_REPO      := quay.io/boson/faas-go-builder
 QUARKUS_JVM_BUILDER_REPO := quay.io/boson/faas-quarkus-jvm-builder
 QUARKUS_NATIVE_BUILDER_REPO := quay.io/boson/faas-quarkus-native-builder
 SPRINGBOOT_BUILDER_REPO := quay.io/boson/faas-springboot-builder
+PYTHON_BUILDER_REPO := quay.io/boson/faas-python-builder
 
 NODEJS_BUILDPACK_REPO  := quay.io/boson/faas-nodejs-bp
 GO_BUILDPACK_REPO      := quay.io/boson/faas-go-bp
 QUARKUS_JVM_BUILDPACK_REPO := quay.io/boson/faas-quarkus-jvm-bp
 QUARKUS_NATIVE_BUILDPACK_REPO := quay.io/boson/faas-quarkus-native-bp
 SPRINGBOOT_BUILDPACK_REPO := quay.io/boson/faas-springboot-bp
+PYTHON_BUILDPACK_REPO := quay.io/boson/faas-python-bp
 
 
 .PHONY: stacks buildpacks builders
@@ -32,13 +34,15 @@ stacks:
 	./stacks/build-stack.sh -v $(VERSION_TAG) stacks/quarkus-jvm
 	./stacks/build-stack.sh -v $(VERSION_TAG) stacks/quarkus-native
 	./stacks/build-stack.sh -v $(VERSION_TAG) stacks/springboot
+	./stacks/build-stack.sh -v $(VERSION_TAG) stacks/python
 
 buildpacks:
 	$(PACK_CMD) package-buildpack $(NODEJS_BUILDPACK_REPO):$(VERSION_TAG) --config ./packages/nodejs/package.toml
 	$(PACK_CMD) package-buildpack $(GO_BUILDPACK_REPO):$(VERSION_TAG) --config ./packages/go/package.toml
 	$(PACK_CMD) package-buildpack $(QUARKUS_JVM_BUILDPACK_REPO):$(VERSION_TAG) --config ./packages/quarkus-jvm/package.toml
 	$(PACK_CMD) package-buildpack $(QUARKUS_NATIVE_BUILDPACK_REPO):$(VERSION_TAG) --config ./packages/quarkus-native/package.toml
 	$(PACK_CMD) package-buildpack $(SPRINGBOOT_BUILDPACK_REPO):$(VERSION_TAG) --config ./packages/springboot/package.toml
+	$(PACK_CMD) package-buildpack $(PYTHON_BUILDPACK_REPO):$(VERSION_TAG) --config ./packages/python/package.toml
 
 builders:
 	TMP_BLDRS=$(shell mktemp -d) && \
@@ -47,11 +51,13 @@ builders:
 	sed "s/{{VERSION}}/$(VERSION_TAG)/g" ./builders/go/builder.toml > $$TMP_BLDRS/go.toml && \
 	sed "s/{{VERSION}}/$(VERSION_TAG)/g" ./builders/quarkus-jvm/builder.toml > $$TMP_BLDRS/quarkus-jvm.toml && \
 	sed "s/{{VERSION}}/$(VERSION_TAG)/g" ./builders/springboot/builder.toml > $$TMP_BLDRS/springboot.toml && \
+	sed "s/{{VERSION}}/$(VERSION_TAG)/g" ./builders/python/builder.toml > $$TMP_BLDRS/python.toml && \
 	$(PACK_CMD) create-builder --pull-policy=never $(NODEJS_BUILDER_REPO):$(VERSION_TAG) --config $$TMP_BLDRS/node.toml && \
 	$(PACK_CMD) create-builder --pull-policy=never $(GO_BUILDER_REPO):$(VERSION_TAG) --config $$TMP_BLDRS/go.toml && \
 	$(PACK_CMD) create-builder --pull-policy=never $(QUARKUS_JVM_BUILDER_REPO):$(VERSION_TAG) --config $$TMP_BLDRS/quarkus-jvm.toml && \
 	$(PACK_CMD) create-builder --pull-policy=never $(QUARKUS_NATIVE_BUILDER_REPO):$(VERSION_TAG) --config $$TMP_BLDRS/quarkus-native.toml && \
 	$(PACK_CMD) create-builder --pull-policy=never $(SPRINGBOOT_BUILDER_REPO):$(VERSION_TAG) --config $$TMP_BLDRS/springboot.toml -v && \
+	$(PACK_CMD) create-builder --pull-policy=never $(PYTHON_BUILDER_REPO):$(VERSION_TAG) --config $$TMP_BLDRS/python.toml -v && \
 	rm -fr $$TMP_BLDRS
 
 publish:
@@ -63,7 +69,7 @@ publish:
 	    docker push $(BUILD_REPO):$$i-$(VERSION_TAG); \
 	done
 
-	for img in $(QUARKUS_NATIVE_BUILDPACK_REPO) $(QUARKUS_JVM_BUILDPACK_REPO) $(QUARKUS_NATIVE_BUILDER_REPO) $(QUARKUS_JVM_BUILDER_REPO) $(NODEJS_BUILDPACK_REPO) $(GO_BUILDPACK_REPO) $(NODEJS_BUILDER_REPO) $(GO_BUILDER_REPO) $(SPRINGBOOT_BUILDPACK_REPO) $(SPRINGBOOT_BUILDER_REPO); do \
+	for img in $(QUARKUS_NATIVE_BUILDPACK_REPO) $(QUARKUS_JVM_BUILDPACK_REPO) $(QUARKUS_NATIVE_BUILDER_REPO) $(QUARKUS_JVM_BUILDER_REPO) $(NODEJS_BUILDPACK_REPO) $(GO_BUILDPACK_REPO) $(NODEJS_BUILDER_REPO) $(GO_BUILDER_REPO) $(SPRINGBOOT_BUILDPACK_REPO) $(SPRINGBOOT_BUILDER_REPO) $(PYTHON_BUILDPACK_REPO) $(PYTHON_BUILDER_REPO); do \
 		docker push $$img:$(VERSION_TAG); \
 		if [ "$(VERSION_TAG)" != "tip" ]; then \
 		    docker tag $$img:$(VERSION_TAG) $$img:latest; \

builders/python/builder.toml

@@ -0,0 +1,16 @@
+# Buildpacks to include in builder
+[[buildpacks]]
+id = "dev.boson.python"
+image = "quay.io/boson/faas-python-bp:{{VERSION}}"
+
+[[order]]
+[[order.group]]
+id = "dev.boson.python"
+
+# Stack that will be used by the builder
+[stack]
+id = "dev.boson.stacks.python"
+# This image is used at runtime
+run-image = "quay.io/boson/faas-stack-run:python-{{VERSION}}"
+# This image is used at build-time
+build-image = "quay.io/boson/faas-stack-build:python-{{VERSION}}"

buildpacks/python/bin/build

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+set -e
+set -o pipefail
+
+echo "---> Python Function Buildpack"
+
+bp_dir=$(cd "$(dirname "$0")"/..; pwd)
+build_dir=$(pwd)
+layers_dir=$1
+
+source "${bp_dir}/lib/build.sh"
+
+app_layer=${layers_dir}/app
+mkdir -p "${app_layer}"
+cat > "$app_layer.toml" << TOML
+launch = true
+build = false
+cache = false
+TOML
+
+# Install function
+echo "---> Installing function"
+ls -l ${build_dir}
+cp -r ${build_dir}/* ${app_layer}
+
+# Install invoker
+echo "---> Installing invoker"
+ls -l ${bp_dir}/runtime
+cp -r ${bp_dir}/runtime ${app_layer}/.invoker
+
+# Install or reuse dependencies
+echo "---> Installing or reusing dependencies"
+environments_layer="${layers_dir}/environments"
+install_or_reuse_deps ${environments_layer}
+
+# TODO: set up production using waitress
+
+cat <<TOML > "${layers_dir}/launch.toml"
+[[processes]]
+type = "web"
+command = "export FLASK_APP=server.py && source $environments_layer/functions/bin/activate && cd $app_layer/.invoker && flask run --host=0.0.0.0 --port=8080"
+TOML

buildpacks/python/bin/detect

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -eo pipefail
+
+if [[ ! -d __pycache__ ]] ; then
+  if [[ ! -f func.py ]] ; then
+    exit 100
+  fi
+fi

buildpacks/python/buildpack.toml

@@ -0,0 +1,9 @@
+api = "0.2"
+
+[buildpack]
+id = "dev.boson.python"
+version = "0.0.1"
+name = "Python Function Buildpack"
+
+[[stacks]]
+id = "dev.boson.stacks.python"

buildpacks/python/lib/build.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+set -e
+
+install_or_reuse_deps() {
+  echo "Installing function invoker dependencies"
+  local layer_dir=$1
+  local env_dir="${layer_dir}/functions"
+
+  touch "${layer_dir}.toml"
+  mkdir -p ${layer_dir}
+
+  echo "Using python version $(python3 --version)"
+
+  if [[ ! -d ${env_dir} ]]; then
+    cd ${layer_dir}
+    echo "Installing virtualenv"
+    pip3 install --user virtualenv
+    echo "Creating function runtime environment"
+    python3 -m venv functions
+    echo "Initializing functions environment"
+    source functions/bin/activate
+    echo "Installing flask"
+    pip3 install flask
+    echo "Installing cloudevents"
+    pip3 install cloudevents
+  fi
+
+  echo "cache = true" > "${layer_dir}.toml"
+  echo "build = true" >> "${layer_dir}.toml"
+  echo "launch = true" >> "${layer_dir}.toml"
+}

buildpacks/python/runtime/server.py

@@ -0,0 +1,24 @@
+import sys
+import os
+
+from flask import Flask, request
+from cloudevents.http import from_http
+
+serverDir = os.path.dirname(__file__)
+funcDir = os.path.realpath(os.path.join(serverDir, ".."))
+sys.path.append(funcDir)
+
+import func
+
+app = Flask(__name__)
+
+# create an endpoint at localhost:3000
+
+@app.route("/", methods=["POST"])
+def handler():
+  # create a CloudEvent
+  event = from_http(request.headers, request.get_data())
+  return func.main(event)
+
+if __name__ == "__main__":
+  app.run(port=8080)

packages/python/package.toml

@@ -0,0 +1,2 @@
+[buildpack]
+uri = "../../buildpacks/python"

stacks/python/build/Dockerfile

@@ -0,0 +1,16 @@
+ARG version=tip
+FROM quay.io/boson/faas-stack-build:ubi8-${version}
+
+ARG stack_id
+ENV CNB_STACK_ID=${stack_id}
+LABEL io.buildpacks.stack.id=${stack_id}
+
+# Install Python 3, tar and a python functions virtual environment
+USER root
+ENV HOME /projects/python-function
+COPY ./python.module /etc/dnf/modules.d
+RUN dnf install --nodocs -y python3 tar
+
+WORKDIR $HOME
+RUN chown cnb:cnb $HOME
+USER cnb

stacks/python/build/python.module

@@ -0,0 +1,5 @@
+[python]
+name=python
+stream=3.8
+profiles=
+state=enabled

stacks/python/run/Dockerfile

@@ -0,0 +1,17 @@
+ARG version=tip
+FROM quay.io/boson/faas-stack-run:ubi8-minimal-${version}
+
+ARG stack_id
+ENV CNB_STACK_ID=${stack_id}
+LABEL io.buildpacks.stack.id=${stack_id}
+
+USER root
+COPY ./python.module /etc/dnf/modules.d
+RUN microdnf install --nodocs -y python3 tar
+
+ENV HOME /projects/python-function
+WORKDIR $HOME
+RUN chown cnb:cnb $HOME
+USER cnb
+
+ENV PORT 8080

stacks/python/run/python.module

@@ -0,0 +1,5 @@
+[python]
+name=python
+stream=3.8
+profiles=
+state=enabled