about summary refs log tree commit diff
path: root/cmake/CompileProtos.cmake
blob: c4bd8982b907d01d525fda5e4dfcce67ab93563d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
# ~~~
# Copyright 2019 Google LLC
#
# 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.
# ~~~

# Introduce a new TARGET property to associate proto files with a target.
#
# We use a function to define the property so it can be called multiple times
# without introducing the property over and over.
function (google_cloud_cpp_add_protos_property)
    set_property(TARGET
                 PROPERTY PROTO_SOURCES
                          BRIEF_DOCS
                          "The list of .proto files for a target."
                          FULL_DOCS
                          "List of .proto files specified for a target.")
endfunction ()

# Generate C++ for .proto files preserving the directory hierarchy
#
# Receives a list of `.proto` file names and (a) creates the runs to convert
# these files to `.pb.h` and `.pb.cc` output files, (b) returns the list of
# `.pb.cc` files and `.pb.h` files in @p HDRS, and (c) creates the list of files
# preserving the directory hierarchy, such that if a `.proto` file says:
#
# import "foo/bar/baz.proto"
#
# the resulting C++ code says:
#
# #include <foo/bar/baz.pb.h>
#
# Use the `PROTO_PATH` option to provide one or more directories to search for
# proto files in the import.
#
# @par Example
#
# google_cloud_cpp_generate_proto( MY_PB_FILES "foo/bar/baz.proto"
# "foo/bar/qux.proto" PROTO_PATH_DIRECTORIES "another/dir/with/protos")
#
# Note that `protoc` the protocol buffer compiler requires your protos to be
# somewhere in the search path defined by the `--proto_path` (aka -I) options.
# For example, if you want to generate the `.pb.{h,cc}` files for
# `foo/bar/baz.proto` then the directory containing `foo` must be in the search
# path.
function (google_cloud_cpp_generate_proto SRCS)
    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
    if (NOT _opt_UNPARSED_ARGUMENTS)
        message(SEND_ERROR "Error: google_cloud_cpp_generate_proto() called"
                           " without any proto files")
        return()
    endif ()

    # Build the list of `--proto_path` options. Use the absolute path for each
    # option given, and do not include any path more than once.
    set(protobuf_include_path)
    foreach (dir ${_opt_PROTO_PATH_DIRECTORIES})
        get_filename_component(absolute_path ${dir} ABSOLUTE)
        list(FIND protobuf_include_path "${absolute_path}"
                  already_in_search_path)
        if (${already_in_search_path} EQUAL -1)
            list(APPEND protobuf_include_path "--proto_path" "${absolute_path}")
        endif ()
    endforeach ()

    set(${SRCS})
    foreach (filename ${_opt_UNPARSED_ARGUMENTS})
        get_filename_component(file_directory "${filename}" DIRECTORY)
        # This gets the filename without the extension, analogous to $(basename
        # "${filename}" .proto)
        get_filename_component(file_stem "${filename}" NAME_WE)

        # Strip all the prefixes in ${_opt_PROTO_PATH_DIRECTORIES} from the
        # source proto directory
        set(D "${file_directory}")
        if (DEFINED _opt_PROTO_PATH_DIRECTORIES)
            foreach (P ${_opt_PROTO_PATH_DIRECTORIES})
                string(REGEX
                       REPLACE "^${P}"
                               ""
                               T
                               "${D}")
                set(D ${T})
            endforeach ()
        endif ()
        set(pb_cc "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.pb.cc")
        set(pb_h "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.pb.h")
        list(APPEND ${SRCS} "${pb_cc}" "${pb_h}")
        add_custom_command(
            OUTPUT "${pb_cc}" "${pb_h}"
            COMMAND $<TARGET_FILE:protobuf::protoc>
                    ARGS
                    --cpp_out "${CMAKE_CURRENT_BINARY_DIR}"
                              ${protobuf_include_path} "${filename}"
            DEPENDS "${filename}" protobuf::protoc
            COMMENT "Running C++ protocol buffer compiler on ${filename}"
            VERBATIM)
    endforeach ()

    set_source_files_properties(${${SRCS}} PROPERTIES GENERATED TRUE)
    set(${SRCS} ${${SRCS}} PARENT_SCOPE)
endfunction ()

# Generate gRPC C++ files from .proto files preserving the directory hierarchy.
#
# Receives a list of `.proto` file names and (a) creates the runs to convert
# these files to `.grpc.pb.h` and `.grpc.pb.cc` output files, (b) returns the
# list of `.grpc.pb.cc` and `.pb.h` files in @p SRCS, and (c) creates the list
# of files preserving the directory hierarchy, such that if a `.proto` file says
#
# import "foo/bar/baz.proto"
#
# the resulting C++ code says:
#
# #include <foo/bar/baz.pb.h>
#
# Use the `PROTO_PATH` option to provide one or more directories to search for
# proto files in the import.
#
# @par Example
#
# google_cloud_cpp_generate_grpc( MY_GRPC_PB_FILES "foo/bar/baz.proto"
# "foo/bar/qux.proto" PROTO_PATH_DIRECTORIES "another/dir/with/protos")
#
# Note that `protoc` the protocol buffer compiler requires your protos to be
# somewhere in the search path defined by the `--proto_path` (aka -I) options.
# For example, if you want to generate the `.pb.{h,cc}` files for
# `foo/bar/baz.proto` then the directory containing `foo` must be in the search
# path.
function (google_cloud_cpp_generate_grpcpp SRCS)
    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
    if (NOT _opt_UNPARSED_ARGUMENTS)
        message(
            SEND_ERROR "Error: google_cloud_cpp_generate_grpc() called without"
                       " any proto files")
        return()
    endif ()

    # Build the list of `--proto_path` options. Use the absolute path for each
    # option given, and do not include any path more than once.
    set(protobuf_include_path)
    foreach (dir ${_opt_PROTO_PATH_DIRECTORIES})
        get_filename_component(absolute_path ${dir} ABSOLUTE)
        list(FIND protobuf_include_path "${absolute_path}"
                  already_in_search_path)
        if (${already_in_search_path} EQUAL -1)
            list(APPEND protobuf_include_path "--proto_path" "${absolute_path}")
        endif ()
    endforeach ()

    set(${SRCS})
    foreach (filename ${_opt_UNPARSED_ARGUMENTS})
        get_filename_component(file_directory "${filename}" DIRECTORY)
        # This gets the filename without the extension, analogous to $(basename
        # "${filename}" .proto)
        get_filename_component(file_stem "${filename}" NAME_WE)

        # Strip all the prefixes in ${_opt_PROTO_PATH_DIRECTORIES} from the
        # source proto directory
        set(D "${file_directory}")
        if (DEFINED _opt_PROTO_PATH_DIRECTORIES)
            foreach (P ${_opt_PROTO_PATH_DIRECTORIES})
                string(REGEX
                       REPLACE "^${P}"
                               ""
                               T
                               "${D}")
                set(D ${T})
            endforeach ()
        endif ()
        set(grpc_pb_cc
            "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.grpc.pb.cc")
        set(grpc_pb_h "${CMAKE_CURRENT_BINARY_DIR}/${D}/${file_stem}.grpc.pb.h")
        list(APPEND ${SRCS} "${grpc_pb_cc}" "${grpc_pb_h}")
        add_custom_command(
            OUTPUT "${grpc_pb_cc}" "${grpc_pb_h}"
            COMMAND
                $<TARGET_FILE:protobuf::protoc>
                ARGS
                --plugin=protoc-gen-grpc=$<TARGET_FILE:gRPC::grpc_cpp_plugin>
                    "--grpc_out=${CMAKE_CURRENT_BINARY_DIR}"
                    "--cpp_out=${CMAKE_CURRENT_BINARY_DIR}"
                    ${protobuf_include_path} "${filename}"
            DEPENDS "${filename}" protobuf::protoc gRPC::grpc_cpp_plugin
            COMMENT "Running gRPC C++ protocol buffer compiler on ${filename}"
            VERBATIM)
    endforeach ()

    set_source_files_properties(${${SRCS}} PROPERTIES GENERATED TRUE)
    set(${SRCS} ${${SRCS}} PARENT_SCOPE)
endfunction ()

include(GNUInstallDirs)

# Install headers for a C++ proto library.
function (google_cloud_cpp_install_proto_library_headers target)
    get_target_property(target_sources ${target} SOURCES)
    foreach (header ${target_sources})
        # Skip anything that is not a header file.
        if (NOT "${header}" MATCHES "\\.h$")
            continue()
        endif ()
        string(REPLACE "${CMAKE_CURRENT_BINARY_DIR}/"
                       ""
                       relative
                       "${header}")
        get_filename_component(dir "${relative}" DIRECTORY)
        install(FILES "${header}" DESTINATION
                      "${CMAKE_INSTALL_INCLUDEDIR}/${dir}")
    endforeach ()
endfunction ()

# Install protos for a C++ proto library.
function (google_cloud_cpp_install_proto_library_protos target strip_prefix)
    get_target_property(target_protos ${target} PROTO_SOURCES)
    foreach (proto ${target_protos})
        # Skip anything that is not a header file.
        if (NOT "${proto}" MATCHES "\\.proto$")
            continue()
        endif ()
	string(REPLACE "${strip_prefix}/"
		       ""
		       relative
		       "${proto}")
        get_filename_component(dir "${relative}" DIRECTORY)
        # This is modeled after the Protobuf library, it installs the basic
        # protos (think google/protobuf/any.proto) in the include directory for
        # C/C++ code. :shrug:
        install(FILES "${proto}" DESTINATION
                      "${CMAKE_INSTALL_INCLUDEDIR}/${dir}")
    endforeach ()
endfunction ()

function (google_cloud_cpp_proto_library libname)
    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
    if (NOT _opt_UNPARSED_ARGUMENTS)
        message(SEND_ERROR "Error: google_cloud_cpp_proto_library() called"
                           " without any proto files")
        return()
    endif ()

    google_cloud_cpp_generate_proto(proto_sources
                                    ${_opt_UNPARSED_ARGUMENTS}
                                    PROTO_PATH_DIRECTORIES
                                    ${_opt_PROTO_PATH_DIRECTORIES})

    add_library(${libname} ${proto_sources})
    set_property(TARGET ${libname}
                 PROPERTY PROTO_SOURCES ${_opt_UNPARSED_ARGUMENTS})
    target_link_libraries(${libname}
                          PUBLIC gRPC::grpc++ gRPC::grpc protobuf::libprotobuf)
    target_include_directories(
        ${libname}
        PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}>
               $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}>
               $<INSTALL_INTERFACE:include>)
endfunction ()

function (google_cloud_cpp_grpcpp_library libname)
    cmake_parse_arguments(_opt "" "" "PROTO_PATH_DIRECTORIES" ${ARGN})
    if (NOT _opt_UNPARSED_ARGUMENTS)
        message(SEND_ERROR "Error: google_cloud_cpp_proto_library() called"
                           " without any proto files")
        return()
    endif ()

    google_cloud_cpp_generate_grpcpp(grpcpp_sources
                                     ${_opt_UNPARSED_ARGUMENTS}
                                     PROTO_PATH_DIRECTORIES
                                     ${_opt_PROTO_PATH_DIRECTORIES})
    google_cloud_cpp_proto_library(${libname}
                                   ${_opt_UNPARSED_ARGUMENTS}
                                   PROTO_PATH_DIRECTORIES
                                   ${_opt_PROTO_PATH_DIRECTORIES})
    target_sources(${libname} PRIVATE ${grpcpp_sources})
endfunction ()