jenkins/build_defs/templates.bzl - continuous-integration - Git at Google

 # Copyright 2017 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.

 # Rules for templating / files layout

 def _expand_template_impl(ctx):
   """Simply spawn the template-engine in a rule."""
   variables = [
       "--variable=%s=%s" % (k, ctx.attr.substitutions[k])
       for k in ctx.attr.substitutions
   ]
   d = {str(ctx.attr.deps[i].label): ctx.files.deps[i].path
        for i in range(0, len(ctx.attr.deps))}
   imports = ["--imports=%s=%s" % (k, d[k]) for k in d]
   imports += ["--imports=%s=%s" % (k, d[str(ctx.label.relative(ctx.attr.deps_aliases[k]))])
               for k in ctx.attr.deps_aliases]
   ctx.action(
       executable = ctx.executable._engine,
       arguments = [
         "--executable" if ctx.attr.executable else "--noexecutable",
         "--template=%s" % ctx.file.template.path,
         "--output=%s" % ctx.outputs.out.path,
       ] + variables + imports,
       inputs = [ctx.file.template] + ctx.files.deps,
       outputs = [ctx.outputs.out],
       )

 expand_template = rule(
     attrs = {
         "template": attr.label(
             mandatory = True,
             allow_files = True,
             single_file = True,
         ),
         "deps": attr.label_list(default = [], allow_files = True),
         "deps_aliases": attr.string_dict(default = {}),
         "substitutions": attr.string_dict(mandatory = True),
         "out": attr.output(mandatory = True),
         "executable": attr.bool(default = True),
         "_engine": attr.label(
             default = Label("//templating:template_engine"),
             executable = True,
             cfg="host"),
     },
     implementation = _expand_template_impl,
 )
 """Expand a jinja2 template file.

 This rules expands the file given in template, into the file given by out.

 Args:
   template: The template file to expand.
   deps: additional files to expand, they will be accessible as imports[label]
       in the template environment. If a file ends with .tpl, it is considered
       a template itself and will be expanded.
   deps_aliases: a dictionary of name to label. Each label in that dictionary
       should be present in the deps attribute, and will be make accessible as
       imports[name] in the template environment.
   substitutions: a dictionary of key => values that will appear as variables.key
       in the template environment.
   out: the name of the output file to generate.
   executable: mark the result as excutable if set to True.
 """

 def strip_prefix(path, prefixes):
   for prefix in prefixes:
     if path.startswith(prefix):
       return path[len(prefix):]
   return path

 def strip_suffix(path, suffixes):
   for suffix in suffixes:
     if path.endswith(suffix):
       return path[:-len(suffix)]
   return path

 def _dest_path(f, strip_prefixes, strip_suffixes):
   """Returns the short path of f, stripped of strip_prefixes and strip_suffixes."""
   return strip_suffix(strip_prefix(f.short_path, strip_prefixes), strip_suffixes)

 def _format_path(path_format, path):
   dirsep = path.rfind("/")
   dirname = path[:dirsep] if dirsep > 0 else ""
   basename = path[dirsep+1:] if dirsep > 0 else path
   extsep = basename.rfind(".")
   extension = basename[extsep+1:] if extsep > 0 else ""
   basename = basename[:extsep] if extsep > 0 else basename
   return path_format.format(
       path=path,
       dirname=dirname,
       basename=basename,
       extension=extension
   )

 def _append_inputs(args, inputs, f, path, path_format):
   args.append("--file=%s=%s" % (
       f.path,
       _format_path(path_format, path)
   ))
   inputs.append(f)

 def _merge_files_impl(ctx):
   """Merge a list of config files in a tar ball with the correct layout."""
   output = ctx.outputs.out
   build_tar = ctx.executable._build_tar
   inputs = []
   args = [
       "--output=" + output.path,
       "--directory=" + ctx.attr.directory,
       "--mode=0644",
       ]
   variables = [
       "--variable=%s=%s" % (k, ctx.attr.substitutions[k])
       for k in ctx.attr.substitutions
   ]
   for f in ctx.files.srcs:
     path = _dest_path(f, ctx.attr.strip_prefixes, ctx.attr.strip_suffixes)
     if path.endswith(ctx.attr.template_extension):
       path = path[:-4]
       f2 = ctx.new_file(ctx.label.name + "/" + path)
       ctx.action(
           executable = ctx.executable._engine,
           arguments = [
             "--template=%s" % f.path,
             "--output=%s" % f2.path,
             "--noescape_xml",
           ] + variables,
           inputs = [f],
           outputs = [f2],
       )
       _append_inputs(args, inputs, f2, path, ctx.attr.path_format)
     else:
       _append_inputs(args, inputs, f, path, ctx.attr.path_format)
   ctx.action(
       executable = build_tar,
       arguments = args,
       inputs = inputs,
       outputs = [output],
       mnemonic="MergeFiles"
       )

 merge_files = rule(
     attrs = {
         "srcs": attr.label_list(allow_files=True),
         "template_extension": attr.string(default=".tpl"),
         "directory": attr.string(default="/"),
         "strip_prefixes": attr.string_list(default=[]),
         "strip_suffixes": attr.string_list(default=["-staging", "-test"]),
         "substitutions": attr.string_dict(default={}),
         "path_format": attr.string(default="{path}"),
         "_build_tar": attr.label(
             default=Label("@bazel_tools//tools/build_defs/pkg:build_tar"),
             cfg="host",
             executable=True,
             allow_files=True),
         "_engine": attr.label(
             cfg="host",
             default = Label("//templating:template_engine"),
             executable = True),
     },
     outputs = {"out": "%{name}.tar"},
     implementation = _merge_files_impl,
 )
 """Merge a set of files in a single tarball.

 This rule merge a set of files into one tarball, each file will appear in the
 tarball as a file determined by path_format, strip_prefixes and directory.

 Outputs:
   <name>.tar: the tarball containing all the files in srcs.

 Args:
   srcs: The list of files to merge. If a file is ending with ".tpl" (see
       template_extension), it will get expanded like a template passed to
       expand_template.
   template_extension: extension of files to be considered as template, ".tpl"
       by default.
   directory: base directory for all the files in the resulting tarball.
   strip_prefixes: list of prefixes to strip from the path of the srcs to obtain
       the final path (see path_format).
   strip_suffixes: list of suffixes to strip from the path of the srcs to obtain
       the final path (see path_format).
   substitutions: map of substitutions to make available during template
       expansion. Values of that map will be available as "variables.name" in
       the template environment.
   path_format: format of the final files. Each file will appear in the final
       tarball under "{directory}/{path_format}" where the following string of
       path_format are replaced:
           {path}: path of the input file, removed from prefixes and suffixes,
           {dirname}: directory name of path,
           {basename}: base filename of path,
           {extension}: extension of path
 """
	# Copyright 2017 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.

	# Rules for templating / files layout

	def _expand_template_impl(ctx):
	"""Simply spawn the template-engine in a rule."""
	variables = [
	"--variable=%s=%s" % (k, ctx.attr.substitutions[k])
	for k in ctx.attr.substitutions
	]
	d = {str(ctx.attr.deps[i].label): ctx.files.deps[i].path
	for i in range(0, len(ctx.attr.deps))}
	imports = ["--imports=%s=%s" % (k, d[k]) for k in d]
	imports += ["--imports=%s=%s" % (k, d[str(ctx.label.relative(ctx.attr.deps_aliases[k]))])
	for k in ctx.attr.deps_aliases]
	ctx.action(
	executable = ctx.executable._engine,
	arguments = [
	"--executable" if ctx.attr.executable else "--noexecutable",
	"--template=%s" % ctx.file.template.path,
	"--output=%s" % ctx.outputs.out.path,
	] + variables + imports,
	inputs = [ctx.file.template] + ctx.files.deps,
	outputs = [ctx.outputs.out],
	)

	expand_template = rule(
	attrs = {
	"template": attr.label(
	mandatory = True,
	allow_files = True,
	single_file = True,
	),
	"deps": attr.label_list(default = [], allow_files = True),
	"deps_aliases": attr.string_dict(default = {}),
	"substitutions": attr.string_dict(mandatory = True),
	"out": attr.output(mandatory = True),
	"executable": attr.bool(default = True),
	"_engine": attr.label(
	default = Label("//templating:template_engine"),
	executable = True,
	cfg="host"),
	},
	implementation = _expand_template_impl,
	)
	"""Expand a jinja2 template file.

	This rules expands the file given in template, into the file given by out.

	Args:
	template: The template file to expand.
	deps: additional files to expand, they will be accessible as imports[label]
	in the template environment. If a file ends with .tpl, it is considered
	a template itself and will be expanded.
	deps_aliases: a dictionary of name to label. Each label in that dictionary
	should be present in the deps attribute, and will be make accessible as
	imports[name] in the template environment.
	substitutions: a dictionary of key => values that will appear as variables.key
	in the template environment.
	out: the name of the output file to generate.
	executable: mark the result as excutable if set to True.
	"""

	def strip_prefix(path, prefixes):
	for prefix in prefixes:
	if path.startswith(prefix):
	return path[len(prefix):]
	return path

	def strip_suffix(path, suffixes):
	for suffix in suffixes:
	if path.endswith(suffix):
	return path[:-len(suffix)]
	return path

	def _dest_path(f, strip_prefixes, strip_suffixes):
	"""Returns the short path of f, stripped of strip_prefixes and strip_suffixes."""
	return strip_suffix(strip_prefix(f.short_path, strip_prefixes), strip_suffixes)

	def _format_path(path_format, path):
	dirsep = path.rfind("/")
	dirname = path[:dirsep] if dirsep > 0 else ""
	basename = path[dirsep+1:] if dirsep > 0 else path
	extsep = basename.rfind(".")
	extension = basename[extsep+1:] if extsep > 0 else ""
	basename = basename[:extsep] if extsep > 0 else basename
	return path_format.format(
	path=path,
	dirname=dirname,
	basename=basename,
	extension=extension
	)

	def _append_inputs(args, inputs, f, path, path_format):
	args.append("--file=%s=%s" % (
	f.path,
	_format_path(path_format, path)
	))
	inputs.append(f)

	def _merge_files_impl(ctx):
	"""Merge a list of config files in a tar ball with the correct layout."""
	output = ctx.outputs.out
	build_tar = ctx.executable._build_tar
	inputs = []
	args = [
	"--output=" + output.path,
	"--directory=" + ctx.attr.directory,
	"--mode=0644",
	]
	variables = [
	"--variable=%s=%s" % (k, ctx.attr.substitutions[k])
	for k in ctx.attr.substitutions
	]
	for f in ctx.files.srcs:
	path = _dest_path(f, ctx.attr.strip_prefixes, ctx.attr.strip_suffixes)
	if path.endswith(ctx.attr.template_extension):
	path = path[:-4]
	f2 = ctx.new_file(ctx.label.name + "/" + path)
	ctx.action(
	executable = ctx.executable._engine,
	arguments = [
	"--template=%s" % f.path,
	"--output=%s" % f2.path,
	"--noescape_xml",
	] + variables,
	inputs = [f],
	outputs = [f2],
	)
	_append_inputs(args, inputs, f2, path, ctx.attr.path_format)
	else:
	_append_inputs(args, inputs, f, path, ctx.attr.path_format)
	ctx.action(
	executable = build_tar,
	arguments = args,
	inputs = inputs,
	outputs = [output],
	mnemonic="MergeFiles"
	)

	merge_files = rule(
	attrs = {
	"srcs": attr.label_list(allow_files=True),
	"template_extension": attr.string(default=".tpl"),
	"directory": attr.string(default="/"),
	"strip_prefixes": attr.string_list(default=[]),
	"strip_suffixes": attr.string_list(default=["-staging", "-test"]),
	"substitutions": attr.string_dict(default={}),
	"path_format": attr.string(default="{path}"),
	"_build_tar": attr.label(
	default=Label("@bazel_tools//tools/build_defs/pkg:build_tar"),
	cfg="host",
	executable=True,
	allow_files=True),
	"_engine": attr.label(
	cfg="host",
	default = Label("//templating:template_engine"),
	executable = True),
	},
	outputs = {"out": "%{name}.tar"},
	implementation = _merge_files_impl,
	)
	"""Merge a set of files in a single tarball.

	This rule merge a set of files into one tarball, each file will appear in the
	tarball as a file determined by path_format, strip_prefixes and directory.

	Outputs:
	<name>.tar: the tarball containing all the files in srcs.

	Args:
	srcs: The list of files to merge. If a file is ending with ".tpl" (see
	template_extension), it will get expanded like a template passed to
	expand_template.
	template_extension: extension of files to be considered as template, ".tpl"
	by default.
	directory: base directory for all the files in the resulting tarball.
	strip_prefixes: list of prefixes to strip from the path of the srcs to obtain
	the final path (see path_format).
	strip_suffixes: list of suffixes to strip from the path of the srcs to obtain
	the final path (see path_format).
	substitutions: map of substitutions to make available during template
	expansion. Values of that map will be available as "variables.name" in
	the template environment.
	path_format: format of the final files. Each file will appear in the final
	tarball under "{directory}/{path_format}" where the following string of
	path_format are replaced:
	{path}: path of the input file, removed from prefixes and suffixes,
	{dirname}: directory name of path,
	{basename}: base filename of path,
	{extension}: extension of path
	"""