| # Copyright 2022 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. |
| |
| """Rule for simple expansion of template files.""" |
| |
| def _template_rule_impl(ctx): |
| """Modifies ctx.file.src keys in ctx.attr.substitutions with corresponding values.""" |
| ctx.actions.expand_template( |
| template = ctx.file.src, |
| output = ctx.outputs.out, |
| substitutions = ctx.attr.substitutions, |
| ) |
| |
| # Rule for simple expansion of template files. Modifies the templates in src substituting the keys |
| # in substitutions with the corresponding values; the result is output to out. |
| # |
| # Borrowed from TensorFlow (https://github.com/tensorflow/tensorflow) |
| # |
| # Typical usage: |
| # template_rule( |
| # name = "ExpandMyTemplate", |
| # src = "my.template", |
| # out = "my.txt", |
| # substitutions = { |
| # "$VAR1": "foo", |
| # "$VAR2": "bar", |
| # } |
| # ) |
| # |
| # Args: |
| # name: The name of the rule. |
| # src: The template file to expand |
| # out: The destination of the expanded file |
| # substitutions: A dictionary mapping strings to their substitutions |
| template_rule = rule( |
| attrs = { |
| "src": attr.label( |
| mandatory = True, |
| allow_single_file = True, |
| ), |
| "substitutions": attr.string_dict(mandatory = True), |
| "out": attr.output(mandatory = True), |
| }, |
| # output_to_genfiles is required for header files. |
| output_to_genfiles = True, |
| implementation = _template_rule_impl, |
| ) |