aboutsummaryrefslogtreecommitdiffhomepage
path: root/protobuf.bzl
blob: 4226a1424c1b1a7d3f4933af453b151ac99a88c6 (plain)
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
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
def _GetPath(ctx, path):
  if ctx.label.workspace_root:
    return ctx.label.workspace_root + '/' + path
  else:
    return path

def _IsNewExternal(ctx):
  # Bazel 0.4.4 and older have genfiles paths that look like:
  #   bazel-out/local-fastbuild/genfiles/external/repo/foo
  # After the exec root rearrangement, they look like:
  #   ../repo/bazel-out/local-fastbuild/genfiles/foo
  return ctx.label.workspace_root.startswith("../")

def _GenDir(ctx):
  if _IsNewExternal(ctx):
    # We are using the fact that Bazel 0.4.4+ provides repository-relative paths
    # for ctx.genfiles_dir.
    return ctx.genfiles_dir.path + (
        "/" + ctx.attr.includes[0] if ctx.attr.includes and ctx.attr.includes[0] else "")
  # This means that we're either in the old version OR the new version in the local repo.
  # Either way, appending the source path to the genfiles dir works.
  return ctx.var["GENDIR"] + "/" + _SourceDir(ctx)

def _SourceDir(ctx):
  if not ctx.attr.includes:
    return ctx.label.workspace_root
  if not ctx.attr.includes[0]:
    return _GetPath(ctx, ctx.label.package)
  if not ctx.label.package:
    return _GetPath(ctx, ctx.attr.includes[0])
  return _GetPath(ctx, ctx.label.package + '/' + ctx.attr.includes[0])

def _CcHdrs(srcs, use_grpc_plugin=False):
  ret = [s[:-len(".proto")] + ".pb.h" for s in srcs]
  if use_grpc_plugin:
    ret += [s[:-len(".proto")] + ".grpc.pb.h" for s in srcs]
  return ret

def _CcSrcs(srcs, use_grpc_plugin=False):
  ret = [s[:-len(".proto")] + ".pb.cc" for s in srcs]
  if use_grpc_plugin:
    ret += [s[:-len(".proto")] + ".grpc.pb.cc" for s in srcs]
  return ret

def _CcOuts(srcs, use_grpc_plugin=False):
  return _CcHdrs(srcs, use_grpc_plugin) + _CcSrcs(srcs, use_grpc_plugin)

def _PyOuts(srcs, use_grpc_plugin=False):
  ret = [s[:-len(".proto")] + "_pb2.py" for s in srcs]
  if use_grpc_plugin:
    ret += [s[:-len(".proto")] + "_pb2_grpc.py" for s in srcs]
  return ret

def _RelativeOutputPath(path, include, dest=""):
  if include == None:
    return path

  if not path.startswith(include):
    fail("Include path %s isn't part of the path %s." % (include, path))

  if include and include[-1] != '/':
    include = include + '/'
  if dest and dest[-1] != '/':
    dest = dest + '/'

  path = path[len(include):]
  return dest + path

def _proto_gen_impl(ctx):
  """General implementation for generating protos"""
  srcs = ctx.files.srcs
  deps = []
  deps += ctx.files.srcs
  source_dir = _SourceDir(ctx)
  gen_dir = _GenDir(ctx)
  if source_dir:
    import_flags = ["-I" + source_dir, "-I" + gen_dir]
  else:
    import_flags = ["-I."]

  for dep in ctx.attr.deps:
    import_flags += dep.proto.import_flags
    deps += dep.proto.deps

  args = []
  if ctx.attr.gen_cc:
    args += ["--cpp_out=" + gen_dir]
  if ctx.attr.gen_py:
    args += ["--python_out=" + gen_dir]

  inputs = srcs + deps
  if ctx.executable.plugin:
    plugin = ctx.executable.plugin
    lang = ctx.attr.plugin_language
    if not lang and plugin.basename.startswith('protoc-gen-'):
      lang = plugin.basename[len('protoc-gen-'):]
    if not lang:
      fail("cannot infer the target language of plugin", "plugin_language")

    outdir = gen_dir
    if ctx.attr.plugin_options:
      outdir = ",".join(ctx.attr.plugin_options) + ":" + outdir
    args += ["--plugin=protoc-gen-%s=%s" % (lang, plugin.path)]
    args += ["--%s_out=%s" % (lang, outdir)]
    inputs += [plugin]

  if args:
    ctx.action(
        inputs=inputs,
        outputs=ctx.outputs.outs,
        arguments=args + import_flags + [s.path for s in srcs],
        executable=ctx.executable.protoc,
        mnemonic="ProtoCompile",
        use_default_shell_env=True,
    )

  return struct(
      proto=struct(
          srcs=srcs,
          import_flags=import_flags,
          deps=deps,
      ),
  )

proto_gen = rule(
    attrs = {
        "srcs": attr.label_list(allow_files = True),
        "deps": attr.label_list(providers = ["proto"]),
        "includes": attr.string_list(),
        "protoc": attr.label(
            cfg = "host",
            executable = True,
            single_file = True,
            mandatory = True,
        ),
        "plugin": attr.label(
            cfg = "host",
            allow_files = True,
            executable = True,
        ),
        "plugin_language": attr.string(),
        "plugin_options": attr.string_list(),
        "gen_cc": attr.bool(),
        "gen_py": attr.bool(),
        "outs": attr.output_list(),
    },
    output_to_genfiles = True,
    implementation = _proto_gen_impl,
)
"""Generates codes from Protocol Buffers definitions.

This rule helps you to implement Skylark macros specific to the target
language. You should prefer more specific `cc_proto_library `,
`py_proto_library` and others unless you are adding such wrapper macros.

Args:
  srcs: Protocol Buffers definition files (.proto) to run the protocol compiler
    against.
  deps: a list of dependency labels; must be other proto libraries.
  includes: a list of include paths to .proto files.
  protoc: the label of the protocol compiler to generate the sources.
  plugin: the label of the protocol compiler plugin to be passed to the protocol
    compiler.
  plugin_language: the language of the generated sources
  plugin_options: a list of options to be passed to the plugin
  gen_cc: generates C++ sources in addition to the ones from the plugin.
  gen_py: generates Python sources in addition to the ones from the plugin.
  outs: a list of labels of the expected outputs from the protocol compiler.
"""

def cc_proto_library(
        name,
        srcs=[],
        deps=[],
        cc_libs=[],
        include=None,
        protoc="@com_google_protobuf//:protoc",
        internal_bootstrap_hack=False,
        use_grpc_plugin=False,
        default_runtime="@com_google_protobuf//:protobuf",
        **kargs):
  """Bazel rule to create a C++ protobuf library from proto source files

  NOTE: the rule is only an internal workaround to generate protos. The
  interface may change and the rule may be removed when bazel has introduced
  the native rule.

  Args:
    name: the name of the cc_proto_library.
    srcs: the .proto files of the cc_proto_library.
    deps: a list of dependency labels; must be cc_proto_library.
    cc_libs: a list of other cc_library targets depended by the generated
        cc_library.
    include: a string indicating the include path of the .proto files.
    protoc: the label of the protocol compiler to generate the sources.
    internal_bootstrap_hack: a flag indicate the cc_proto_library is used only
        for bootstraping. When it is set to True, no files will be generated.
        The rule will simply be a provider for .proto files, so that other
        cc_proto_library can depend on it.
    use_grpc_plugin: a flag to indicate whether to call the grpc C++ plugin
        when processing the proto files.
    default_runtime: the implicitly default runtime which will be depended on by
        the generated cc_library target.
    **kargs: other keyword arguments that are passed to cc_library.

  """

  includes = []
  if include != None:
    includes = [include]

  if internal_bootstrap_hack:
    # For pre-checked-in generated files, we add the internal_bootstrap_hack
    # which will skip the codegen action.
    proto_gen(
        name=name + "_genproto",
        srcs=srcs,
        deps=[s + "_genproto" for s in deps],
        includes=includes,
        protoc=protoc,
        visibility=["//visibility:public"],
    )
    # An empty cc_library to make rule dependency consistent.
    native.cc_library(
        name=name,
        **kargs)
    return

  grpc_cpp_plugin = None
  if use_grpc_plugin:
    grpc_cpp_plugin = "//external:grpc_cpp_plugin"

  gen_srcs = _CcSrcs(srcs, use_grpc_plugin)
  gen_hdrs = _CcHdrs(srcs, use_grpc_plugin)
  outs = gen_srcs + gen_hdrs

  proto_gen(
      name=name + "_genproto",
      srcs=srcs,
      deps=[s + "_genproto" for s in deps],
      includes=includes,
      protoc=protoc,
      plugin=grpc_cpp_plugin,
      plugin_language="grpc",
      gen_cc=1,
      outs=outs,
      visibility=["//visibility:public"],
  )

  if default_runtime and not default_runtime in cc_libs:
    cc_libs = cc_libs + [default_runtime]
  if use_grpc_plugin:
    cc_libs = cc_libs + ["//external:grpc_lib"]

  native.cc_library(
      name=name,
      srcs=gen_srcs,
      hdrs=gen_hdrs,
      deps=cc_libs + deps,
      includes=includes,
      **kargs)

def internal_gen_well_known_protos_java(srcs):
  """Bazel rule to generate the gen_well_known_protos_java genrule

  Args:
    srcs: the well known protos
  """
  root = Label("%s//protobuf_java" % (native.repository_name())).workspace_root
  pkg = native.package_name() + "/" if native.package_name() else ""
  if root == "":
    include = " -I%ssrc " % pkg
  else:
    include = " -I%s/%ssrc " % (root, pkg)
  native.genrule(
    name = "gen_well_known_protos_java",
    srcs = srcs,
    outs = [
        "wellknown.srcjar",
    ],
    cmd = "$(location :protoc) --java_out=$(@D)/wellknown.jar" +
          " %s $(SRCS) " % include +
          " && mv $(@D)/wellknown.jar $(@D)/wellknown.srcjar",
    tools = [":protoc"],
  )

def internal_copied_filegroup(name, srcs, strip_prefix, dest, **kwargs):
  """Macro to copy files to a different directory and then create a filegroup.

  This is used by the //:protobuf_python py_proto_library target to work around
  an issue caused by Python source files that are part of the same Python
  package being in separate directories.

  Args:
    srcs: The source files to copy and add to the filegroup.
    strip_prefix: Path to the root of the files to copy.
    dest: The directory to copy the source files into.
    **kwargs: extra arguments that will be passesd to the filegroup.
  """
  outs = [_RelativeOutputPath(s, strip_prefix, dest) for s in srcs]

  native.genrule(
      name = name + "_genrule",
      srcs = srcs,
      outs = outs,
      cmd = " && ".join(
          ["cp $(location %s) $(location %s)" %
           (s, _RelativeOutputPath(s, strip_prefix, dest)) for s in srcs]),
  )

  native.filegroup(
      name = name,
      srcs = outs,
      **kwargs)

def py_proto_library(
        name,
        srcs=[],
        deps=[],
        py_libs=[],
        py_extra_srcs=[],
        include=None,
        default_runtime="@com_google_protobuf//:protobuf_python",
        protoc="@com_google_protobuf//:protoc",
        use_grpc_plugin=False,
        **kargs):
  """Bazel rule to create a Python protobuf library from proto source files

  NOTE: the rule is only an internal workaround to generate protos. The
  interface may change and the rule may be removed when bazel has introduced
  the native rule.

  Args:
    name: the name of the py_proto_library.
    srcs: the .proto files of the py_proto_library.
    deps: a list of dependency labels; must be py_proto_library.
    py_libs: a list of other py_library targets depended by the generated
        py_library.
    py_extra_srcs: extra source files that will be added to the output
        py_library. This attribute is used for internal bootstrapping.
    include: a string indicating the include path of the .proto files.
    default_runtime: the implicitly default runtime which will be depended on by
        the generated py_library target.
    protoc: the label of the protocol compiler to generate the sources.
    use_grpc_plugin: a flag to indicate whether to call the Python C++ plugin
        when processing the proto files.
    **kargs: other keyword arguments that are passed to cc_library.

  """
  outs = _PyOuts(srcs, use_grpc_plugin)

  includes = []
  if include != None:
    includes = [include]

  grpc_python_plugin = None
  if use_grpc_plugin:
    grpc_python_plugin = "//external:grpc_python_plugin"
    # Note: Generated grpc code depends on Python grpc module. This dependency
    # is not explicitly listed in py_libs. Instead, host system is assumed to
    # have grpc installed.

  proto_gen(
      name=name + "_genproto",
      srcs=srcs,
      deps=[s + "_genproto" for s in deps],
      includes=includes,
      protoc=protoc,
      gen_py=1,
      outs=outs,
      visibility=["//visibility:public"],
      plugin=grpc_python_plugin,
      plugin_language="grpc"
  )

  if default_runtime and not default_runtime in py_libs + deps:
    py_libs = py_libs + [default_runtime]

  native.py_library(
      name=name,
      srcs=outs+py_extra_srcs,
      deps=py_libs+deps,
      imports=includes,
      **kargs)

def internal_protobuf_py_tests(
    name,
    modules=[],
    **kargs):
  """Bazel rules to create batch tests for protobuf internal.

  Args:
    name: the name of the rule.
    modules: a list of modules for tests. The macro will create a py_test for
        each of the parameter with the source "google/protobuf/%s.py"
    kargs: extra parameters that will be passed into the py_test.

  """
  for m in modules:
    s = "python/google/protobuf/internal/%s.py" % m
    native.py_test(
        name="py_%s" % m,
        srcs=[s],
        main=s,
        **kargs)


def check_protobuf_required_bazel_version():
  """For WORKSPACE files, to check the installed version of bazel.

  This ensures bazel supports our approach to proto_library() depending on a
  copied filegroup. (Fixed in bazel 0.5.4)
  """
  expected = apple_common.dotted_version("0.5.4")
  current = apple_common.dotted_version(native.bazel_version)
  if current.compare_to(expected) < 0:
    fail("Bazel must be newer than 0.5.4")