run_binary: runs an executable as an action (#153)

This rule is an alternative for genrule(): it can
run a binary with the desired arguments,
environment, inputs, and outputs, as a single
build action, without shelling out to Bash.

Fixes https://github.com/bazelbuild/bazel-skylib/issues/149
This commit is contained in:
László Csomor 2019-05-21 14:46:09 +02:00 committed by GitHub
parent c585222071
commit bf8a55b668
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@ -121,3 +121,10 @@ stardoc(
input = "//rules:native_binary.bzl",
deps = ["//rules:native_binary"],
)
stardoc(
name = "run_binary_docs",
out = "run_binary_doc_gen.md",
input = "//rules:run_binary.bzl",
deps = ["//rules:run_binary"],
)

75
docs/run_binary_doc.md Executable file
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@ -0,0 +1,75 @@
<a name="#run_binary"></a>
## run_binary
<pre>
run_binary(<a href="#run_binary-name">name</a>, <a href="#run_binary-args">args</a>, <a href="#run_binary-env">env</a>, <a href="#run_binary-outs">outs</a>, <a href="#run_binary-srcs">srcs</a>, <a href="#run_binary-tool">tool</a>)
</pre>
Runs a binary as a build action.<br/><br/>This rule does not require Bash (unlike <code>native.genrule</code>).
### Attributes
<table class="params-table">
<colgroup>
<col class="col-param" />
<col class="col-description" />
</colgroup>
<tbody>
<tr id="run_binary-name">
<td><code>name</code></td>
<td>
<a href="https://bazel.build/docs/build-ref.html#name">Name</a>; required
<p>
A unique name for this target.
</p>
</td>
</tr>
<tr id="run_binary-args">
<td><code>args</code></td>
<td>
List of strings; optional
<p>
Command line arguments of the binary.<br/><br/>Subject to<code><a href="https://docs.bazel.build/versions/master/be/make-variables.html#location">$(location)</a></code> expansion.
</p>
</td>
</tr>
<tr id="run_binary-env">
<td><code>env</code></td>
<td>
<a href="https://bazel.build/docs/skylark/lib/dict.html">Dictionary: String -> String</a>; optional
<p>
Environment variables of the action.<br/><br/>Subject to <code><a href="https://docs.bazel.build/versions/master/be/make-variables.html#location">$(location)</a></code> expansion.
</p>
</td>
</tr>
<tr id="run_binary-outs">
<td><code>outs</code></td>
<td>
List of labels; required
<p>
Output files generated by the action.<br/><br/>These labels are available for <code>$(location)</code> expansion in <code>args</code> and <code>env</code>.
</p>
</td>
</tr>
<tr id="run_binary-srcs">
<td><code>srcs</code></td>
<td>
<a href="https://bazel.build/docs/build-ref.html#labels">List of labels</a>; optional
<p>
Additional inputs of the action.<br/><br/>These labels are available for <code>$(location)</code> expansion in <code>args</code> and <code>env</code>.
</p>
</td>
</tr>
<tr id="run_binary-tool">
<td><code>tool</code></td>
<td>
<a href="https://bazel.build/docs/build-ref.html#labels">Label</a>; required
<p>
The tool to run in the action.<br/><br/>Must be the label of a *_binary rule, of a rule that generates an executable file, or of a file that can be executed as a subprocess (e.g. an .exe or .bat file on Windows or a binary with executable permission on Linux). This label is available for <code>$(location)</code> expansion in <code>args</code> and <code>env</code>.
</p>
</td>
</tr>
</tbody>
</table>

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@ -33,6 +33,12 @@ bzl_library(
deps = ["//rules/private:copy_file_private"],
)
bzl_library(
name = "run_binary",
srcs = ["run_binary.bzl"],
deps = ["//lib:dicts"],
)
# Exported for build_test.bzl to make sure of, it is an implementation detail
# of the rule and should not be directly used by anything else.
exports_files(["empty_test.sh"])

97
rules/run_binary.bzl Normal file
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@ -0,0 +1,97 @@
# Copyright 2019 The Bazel Authors. All rights reserved.
#
# 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.
"""
run_binary() build rule implementation.
Runs a binary as a build action. This rule does not require Bash (unlike native.genrule()).
"""
load("//lib:dicts.bzl", "dicts")
def _impl(ctx):
tool_as_list = [ctx.attr.tool]
tool_inputs, tool_input_mfs = ctx.resolve_tools(tools = tool_as_list)
args = [
# Expand $(location) / $(locations) in args.
#
# To keep the rule simple, do not expand Make Variables (like *_binary.args usually would).
# (We can add this feature later if users ask for it.)
#
# Also for simple implementation and usage, do not Bash-tokenize the arguments. Without
# tokenization the user can write args=["a b"] to pass (a b) as one argument, but with
# tokenization they would have to write args=["'a b'"] or args=["a\\ b"]. There's no
# documented tokenization function anyway (as of 2019-05-21 ctx.tokenize exists but is
# undocumented, see https://github.com/bazelbuild/bazel/issues/8389).
ctx.expand_location(a, tool_as_list) if "$(location" in a else a
for a in ctx.attr.args
]
envs = {
# Expand $(location) / $(locations) in the values.
k: ctx.expand_location(v, tool_as_list) if "$(location" in v else v
for k, v in ctx.attr.env.items()
}
ctx.actions.run(
outputs = ctx.outputs.outs,
inputs = depset(direct = ctx.files.srcs, transitive = [tool_inputs]),
executable = ctx.executable.tool,
arguments = args,
mnemonic = "RunBinary",
use_default_shell_env = False,
env = dicts.add(ctx.configuration.default_shell_env, envs),
input_manifests = tool_input_mfs,
)
return DefaultInfo(
files = depset(items = ctx.outputs.outs),
runfiles = ctx.runfiles(files = ctx.outputs.outs),
)
run_binary = rule(
implementation = _impl,
doc = "Runs a binary as a build action.<br/><br/>This rule does not require Bash (unlike" +
" <code>native.genrule</code>).",
attrs = {
"tool": attr.label(
doc = "The tool to run in the action.<br/><br/>Must be the label of a *_binary rule," +
" of a rule that generates an executable file, or of a file that can be" +
" executed as a subprocess (e.g. an .exe or .bat file on Windows or a binary" +
" with executable permission on Linux). This label is available for" +
" <code>$(location)</code> expansion in <code>args</code> and <code>env</code>.",
executable = True,
allow_files = True,
mandatory = True,
cfg = "host",
),
"env": attr.string_dict(
doc = "Environment variables of the action.<br/><br/>Subject to " +
" <code><a href=\"https://docs.bazel.build/versions/master/be/make-variables.html#location\">$(location)</a></code>" +
" expansion.",
),
"srcs": attr.label_list(
allow_files = True,
doc = "Additional inputs of the action.<br/><br/>These labels are available for" +
" <code>$(location)</code> expansion in <code>args</code> and <code>env</code>.",
),
"outs": attr.output_list(
mandatory = True,
doc = "Output files generated by the action.<br/><br/>These labels are available for" +
" <code>$(location)</code> expansion in <code>args</code> and <code>env</code>.",
),
"args": attr.string_list(
doc = "Command line arguments of the binary.<br/><br/>Subject to" +
"<code><a href=\"https://docs.bazel.build/versions/master/be/make-variables.html#location\">$(location)</a></code>" +
" expansion.",
),
},
)

166
tests/run_binary/BUILD Normal file
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@ -0,0 +1,166 @@
load("//rules:diff_test.bzl", "diff_test")
load("//rules:run_binary.bzl", "run_binary")
load("//rules:write_file.bzl", "write_file")
package(
default_testonly = 1,
default_visibility = ["//visibility:private"],
)
diff_test(
name = "run_script_test",
file1 = ":run_script.out",
file2 = ":run_script_expected",
)
# Generate this file with write_file instead of checking it in to the source
# tree. This ensures line endings are consistent across "run_script.expected"
# and "run_script.out".
write_file(
name = "run_script_expected",
out = "run_script.expected",
content = [
"arg1=(foo)",
"arg2=(bar)",
"ENV_LOCATION=(a tests/run_binary/BUILD)",
"ENV_LOCATIONS=(b\\ tests/run_binary/BUILD tests/run_binary/printargs.cc)",
"ENV_COMPLEX=(xx/yy \\\"zz)",
"ENV_PATH_BASH=($PATH)",
"ENV_PATH_CMD=(%PATH%)",
# Can't prevent "echo" from adding a newline on Windows, so let's add
# one to the expected output too.
"",
],
)
run_binary(
name = "run_script",
srcs = [
"BUILD",
":dummy_srcs",
],
outs = ["run_script.out"],
# Not testing any complex arguments here, because Windows .bat file argument
# escaping is different from most MSVC-built Windows binaries. We test
# argument escaping in "run_bin".
args = [
"foo",
"bar",
],
# Test complex environment variables. They are location-expanded but not
# Bash-tokenized, and should appear the same for Windows .bat files and Bash
# .sh scripts.
env = {
# Testing $(location) expansion only on source files so the result is
# predictable. The path of generated files depends on the target
# platform.
"ENV_LOCATION": "a $(location BUILD)",
"ENV_LOCATIONS": "b\\ $(locations :dummy_srcs)",
"ENV_COMPLEX": "xx/yy \\\"zz",
"ENV_PATH_BASH": "$PATH",
"ENV_PATH_CMD": "%PATH%",
"OUT": "$(location run_script.out)",
},
tool = ":script",
)
write_file(
name = "script",
# On Windows we need the ".bat" extension.
# On other platforms the extension doesn't matter.
# Therefore we can use ".bat" on every platform.
out = "script.bat",
content = select({
"@bazel_tools//src/conditions:host_windows": [
"@echo>%OUT% arg1=(%1)",
"@echo>>%OUT% arg2=(%2)",
"@echo>>%OUT% ENV_LOCATION=(%ENV_LOCATION%)",
"@echo>>%OUT% ENV_LOCATIONS=(%ENV_LOCATIONS%)",
"@echo>>%OUT% ENV_COMPLEX=(%ENV_COMPLEX%)",
"@echo>>%OUT% ENV_PATH_BASH=(%ENV_PATH_BASH%)",
"@echo>>%OUT% ENV_PATH_CMD=(%ENV_PATH_CMD%)",
],
"//conditions:default": [
"#!/bin/bash",
"echo > \"$OUT\" \"arg1=($1)\"",
"echo >> \"$OUT\" \"arg2=($2)\"",
"echo >> \"$OUT\" \"ENV_LOCATION=($ENV_LOCATION)\"",
"echo >> \"$OUT\" \"ENV_LOCATIONS=($ENV_LOCATIONS)\"",
"echo >> \"$OUT\" \"ENV_COMPLEX=($ENV_COMPLEX)\"",
"echo >> \"$OUT\" \"ENV_PATH_BASH=($ENV_PATH_BASH)\"",
"echo >> \"$OUT\" \"ENV_PATH_CMD=($ENV_PATH_CMD)\"",
],
}),
is_executable = True,
)
diff_test(
name = "run_bin_test",
file1 = ":run_bin.out",
file2 = ":run_bin_expected",
)
# Generate this file with write_file instead of checking it in to the source
# tree. This ensures line endings are consistent across "run_bin.expected"
# and "run_bin.out".
write_file(
name = "run_bin_expected",
out = "run_bin.expected",
content = [
"arg1=(a b)",
"arg2=(\"c d\")",
"arg3=(e\\ f)",
"arg4=(xx/yy\\ \\\"zz)",
"arg5=(tests/run_binary/BUILD)",
"arg6=(tests/run_binary/BUILD tests/run_binary/printargs.cc)",
"arg7=('tests/run_binary/BUILD $tests/run_binary/BUILD')",
"arg8=($PATH)",
"arg9=($$PATH)",
"arg10=(${PATH})",
# Add trailing newline, as printed by printargs.
"",
],
)
run_binary(
name = "run_bin",
srcs = [
"BUILD",
":dummy_srcs",
],
outs = ["run_bin.out"],
# Test complex arguments here. They are location-expanded but not
# Bash-tokenized, and should appear the same on every platform.
args = [
"a b",
"\"c d\"",
"e\\ f",
"xx/yy\\ \\\"zz",
# Testing $(location) expansion only on source files so the result is
# predictable. The path of generated files depends on the target
# platform.
"$(location BUILD)",
"$(locations :dummy_srcs)",
"'$(location BUILD) $$(location BUILD)'",
"$PATH",
"$$PATH",
"${PATH}",
],
# Not testing any complex envvars here, because we already did in
# "run_script".
env = {"OUT": "$(location run_bin.out)"},
tool = ":printargs",
)
filegroup(
name = "dummy_srcs",
srcs = [
"BUILD",
"printargs.cc",
],
)
cc_binary(
name = "printargs",
srcs = ["printargs.cc"],
)

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@ -0,0 +1,36 @@
// Copyright 2019 The Bazel Authors. All rights reserved.
//
// 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.
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char** argv) {
char* out_path = getenv("OUT");
if (!out_path || !*out_path) {
fprintf(stderr, "ERROR(" __FILE__ ":%d): envvar OUT is undefined\n",
__LINE__);
return 1;
}
FILE* f = fopen(out_path, "wt");
if (!f) {
fprintf(stderr, "ERROR(" __FILE__ ":%d): could not open output file '%s'\n",
__LINE__, out_path);
return 1;
}
for (int i = 1; i < argc; ++i) {
fprintf(f, "arg%d=(%s)\n", i, argv[i]);
}
fclose(f);
return 0;
}