51 lines
1.7 KiB
Python
51 lines
1.7 KiB
Python
# Copyright 2022 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.
|
|
|
|
"""A rule that performs template expansion.
|
|
"""
|
|
|
|
def _expand_template_impl(ctx):
|
|
ctx.actions.expand_template(
|
|
template = ctx.file.template,
|
|
output = ctx.outputs.out,
|
|
substitutions = ctx.attr.substitutions,
|
|
)
|
|
|
|
expand_template = rule(
|
|
implementation = _expand_template_impl,
|
|
doc = """Template expansion
|
|
|
|
This performs a simple search over the template file for the keys in
|
|
substitutions, and replaces them with the corresponding values.
|
|
|
|
There is no special syntax for the keys. To avoid conflicts, you would need to
|
|
explicitly add delimiters to the key strings, for example "{KEY}" or "@KEY@".""",
|
|
attrs = {
|
|
"template": attr.label(
|
|
mandatory = True,
|
|
allow_single_file = True,
|
|
doc = "The template file to expand.",
|
|
),
|
|
"substitutions": attr.string_dict(
|
|
mandatory = True,
|
|
doc = "A dictionary mapping strings to their substitutions.",
|
|
),
|
|
"out": attr.output(
|
|
mandatory = True,
|
|
doc = "The destination of the expanded file.",
|
|
),
|
|
},
|
|
output_to_genfiles = True,
|
|
)
|