# -*- mode: makefile; -*-

# Copyright The OpenTelemetry Authors

#

# Licensed under the Apache License, Version 2.0 (the "License");

# you may not use this file except in compliance with the License.

# You may obtain a copy of the License at

#

# http://www.apache.org/licenses/LICENSE-2.0

#

# Unless required by applicable law or agreed to in writing, software

# distributed under the License is distributed on an "AS IS" BASIS,

# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

# See the License for the specific language governing permissions and

# limitations under the License.

#

# This Makefile.protos has rules to generate go code for otlp

# exporter. It does it by copying the proto files from

# `exporters/otlp/internal/opentelemetry-proto` (which is a

# submodule that needs to be checked out) into `gen/proto`, changing

# the go_package option to a valid string, generating the go files and

# finally copying the files into the module. The files are not

# generated in place, because protoc generates a too-deep directory

# structure.

#

# Currently, all the generated code is in

# `exporters/otlp/internal/opentelemetry-proto-gen`.

#

# Prereqs: wget (for downloading the zip file with protoc binary),

# unzip (for unpacking the archive), rsync (for copying back the

# generated files).

PROTOC_VERSION := 3.14.0

TOOLS_DIR := $(abspath ./.tools)

TOOLS_MOD_DIR := ./internal/tools

PROTOBUF_VERSION := v1

OTEL_PROTO_SUBMODULE := exporters/otlp/internal/opentelemetry-proto

GEN_TEMP_DIR := gen

SUBMODULE_PROTO_FILES := $(wildcard $(OTEL_PROTO_SUBMODULE)/opentelemetry/proto/*/$(PROTOBUF_VERSION)/*.proto) $(wildcard $(OTEL_PROTO_SUBMODULE)/opentelemetry/proto/collector/*/$(PROTOBUF_VERSION)/*.proto)

ifeq ($(strip $(SUBMODULE_PROTO_FILES)),)

$(error Submodule at $(OTEL_PROTO_SUBMODULE) is not checked out, use "git submodule update --init")

endif

PROTOBUF_GEN_DIR := exporters/otlp/internal/opentelemetry-proto-gen

PROTOBUF_TEMP_DIR := $(GEN_TEMP_DIR)/pb-go

PROTO_SOURCE_DIR := $(GEN_TEMP_DIR)/proto

SOURCE_PROTO_FILES := $(subst $(OTEL_PROTO_SUBMODULE),$(PROTO_SOURCE_DIR),$(SUBMODULE_PROTO_FILES))

.DEFAULT_GOAL := protobuf

UNAME_S := $(shell uname -s)

UNAME_M := $(shell uname -m)

ifeq ($(UNAME_S),Linux)

PROTOC_OS := linux

PROTOC_ARCH := $(UNAME_M)

else ifeq ($(UNAME_S),Darwin)

PROTOC_OS := osx

PROTOC_ARCH := x86_64

endif

PROTOC_ZIP_URL := https://github.com/protocolbuffers/protobuf/releases/download/v$(PROTOC_VERSION)/protoc-$(PROTOC_VERSION)-$(PROTOC_OS)-$(PROTOC_ARCH).zip

$(TOOLS_DIR)/PROTOC_$(PROTOC_VERSION):

@rm -f "$(TOOLS_DIR)"/PROTOC_* && \

touch "$@"

# Depend on a versioned file (like PROTOC_3.14.0), so when version

# gets bumped, we will depend on a nonexistent file and thus download

# a newer version.

$(TOOLS_DIR)/protoc/bin/protoc: $(TOOLS_DIR)/PROTOC_$(PROTOC_VERSION)

echo "Fetching protoc $(PROTOC_VERSION)" && \

rm -rf $(TOOLS_DIR)/protoc && \

wget -O $(TOOLS_DIR)/protoc.zip $(PROTOC_ZIP_URL) && \

unzip $(TOOLS_DIR)/protoc.zip -d $(TOOLS_DIR)/protoc-tmp && \

rm $(TOOLS_DIR)/protoc.zip && \

touch $(TOOLS_DIR)/protoc-tmp/bin/protoc && \

mv $(TOOLS_DIR)/protoc-tmp $(TOOLS_DIR)/protoc

$(TOOLS_DIR)/protoc-gen-gogofast: $(TOOLS_MOD_DIR)/go.mod $(TOOLS_MOD_DIR)/go.sum $(TOOLS_MOD_DIR)/tools.go

cd $(TOOLS_MOD_DIR) && \

go build -o $(TOOLS_DIR)/protoc-gen-gogofast github.com/gogo/protobuf/protoc-gen-gogofast && \

go mod tidy

# Return a sed expression for replacing the go_package option in proto

# file with a one that's valid for us.

#

# Example: $(call get-sed-expr,$(PROTOBUF_GEN_DIR))

define get-sed-expr

's,go_package = "github.com/open-telemetry/opentelemetry-proto/gen/go,go_package = "go.opentelemetry.io/otel/$(1),'

endef

.PHONY: protobuf

protobuf: protobuf-source gen-protobuf copy-protobufs

.PHONY: protobuf-source

protobuf-source: $(SOURCE_PROTO_FILES)

# This copies proto files from submodule into $(PROTO_SOURCE_DIR),

# thus satisfying the $(SOURCE_PROTO_FILES) prerequisite. The copies

# have their package name replaced by go.opentelemetry.io/otel.

$(PROTO_SOURCE_DIR)/%.proto: $(OTEL_PROTO_SUBMODULE)/%.proto

@ \

mkdir -p $(@D); \

sed -e $(call get-sed-expr,$(PROTOBUF_GEN_DIR)) "$<" >"$@.tmp"; \

mv "$@.tmp" "$@"

.PHONY: gen-protobuf

gen-protobuf: $(SOURCE_PROTO_FILES) $(TOOLS_DIR)/protoc-gen-gogofast $(TOOLS_DIR)/protoc/bin/protoc

@ \

mkdir -p "$(PROTOBUF_TEMP_DIR)"; \

set -e; for f in $^; do \

if [[ "$${f}" == $(TOOLS_DIR)/* ]]; then continue; fi; \

echo "protoc $${f#"$(PROTO_SOURCE_DIR)/"}"; \

PATH="$(TOOLS_DIR):$${PATH}" $(TOOLS_DIR)/protoc/bin/protoc --proto_path="$(PROTO_SOURCE_DIR)" --gogofast_out="plugins=grpc:$(PROTOBUF_TEMP_DIR)" "$${f}"; \

done

.PHONY: copy-protobufs

copy-protobufs:

@rsync -a $(PROTOBUF_TEMP_DIR)/go.opentelemetry.io/otel/exporters .

.PHONY: clean

clean:

rm -rf $(GEN_TEMP_DIR)