google-api-ruby-client/google-apis-generator/lib/google/apis/generator/template.rb

125 lines
3.8 KiB
Ruby

# Copyright 2015 Google Inc.
#
# 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.
require 'active_support/inflector'
require 'erb'
require 'ostruct'
module Google
module Apis
# @private
class Generator
# Directory containing ERB templates
TEMPLATE_DIR = File.expand_path('../templates', __FILE__)
# Helpers used in ERB templates
module TemplateHelpers
# Get the include path for a ruby module/class
#
# @param [String] module_name
# Fully qualified module/class name
# @return [String]
# Path to file
def to_path(module_name)
ActiveSupport::Inflector.underscore(module_name)
end
# Render a block comment
#
# @param [String] str
# Comment string
# @param [Fixnum] spaces_before
# Number of spaces to indent the comment hash
# @param [Fixnum] spaces_after
# Number of spaces to indent after the comment hash for subsequent lines
# @return [String] formatted comment
def block_comment(str, spaces_before = 0, spaces_after = 0)
return '' if str.nil?
pre = ' ' * spaces_before
post = ' ' * spaces_after
lines = str.gsub(/([{}])/, '`').scan(/.{1,78}(?:\W|$)/).map(&:strip)
lines.join("\n" + pre + '#' + post)
end
# Indent a block of text
#
# @param [String] str
# Content to indent
# @param [Fixnum] spaces
# Number of spaces to indent
# @return [String] formatted content
def indent(str, spaces)
pre = ' ' * spaces
str = pre + str.split(/\n/).join("\n" + pre) + "\n"
return str unless str.strip.empty?
nil
end
# Include a partial inside a template.
#
# @private
# @param [String] partial
# Name of the template
# @param [Hash] context
# Context used to render
# @return [String] rendered content
def include(partial, context)
template = Template.new(sprintf('_%s.tmpl', partial))
template.render(context)
end
end
# Holds local vars/helpers for template rendering
class Context < OpenStruct
include TemplateHelpers
# Get the context for ERB evaluation
# @return [Binding]
def to_binding
binding
end
end
# ERB template for the code generator
class Template
# Loads a template from the template dir. Automatically
# appends the .tmpl suffix
#
# @param [String] template_name
# Name of the template file
def self.load(template_name)
Template.new(sprintf('%s.tmpl', template_name))
end
# @param [String] template_name
# Name of the template file
def initialize(template_name)
file = File.join(TEMPLATE_DIR, template_name)
@erb = ERB.new(File.read(file), nil, '-')
end
# Render the template
#
# @param [Hash] context
# Variables to set when rendering the template
# @return [String] rendered template
def render(context)
ctx = Context.new(context)
@erb.result(ctx.to_binding)
end
end
end
end
end