cookbooks/fb_apache/libraries/default.rb

#
# vim: syntax=ruby:expandtab:shiftwidth=2:softtabstop=2:tabstop=2
#
# Copyright (c) 2016-present, Facebook, Inc.
# 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.
#

module FB
  class Apache
    # Any exceptions to the normal hash->apache 1:1 mapping
    HANDLERS = {
      '_rewrites' => 'template_rewrite_helper',
    }.freeze

    def self.indentstr(indent)
      '  ' * indent
    end

    # Map a hash to a apache-style syntax
    def self.template_hash_handler(buf, indent, kw, data)
      if HANDLERS.keys.include?(kw)
        self.send(HANDLERS[kw], buf, indent, kw, data)
        return
      end
      buf << indentstr(indent)
      buf << "<#{kw}>\n"
      data.each do |key, val|
        case val
        when String
          buf << indentstr(indent + 1)
          buf << "#{key} #{val}\n"
        when Hash
          template_hash_handler(buf, indent + 1, key, val)
        end
      end
      buf << indentstr(indent)
      buf << "</#{kw.split[0]}>\n"
    end

    # Helper for rewrite syntax
    def self.template_rewrite_helper(buf, _indent, _key, rules)
      rules.each do |name, ruleset|
        buf << indentstr(1)
        buf << "# #{name}\n"
        ruleset['conditions']&.each do |cond|
          buf << indentstr(1)
          buf << "RewriteCond #{cond}\n"
        end
        buf << indentstr(1)
        buf << "RewriteRule #{ruleset['rule']}\n\n"
      end
    end

    # given a list of modules return the packages they require
    def self.get_module_packages(mods, pkgs)
      mods.map { |mod| pkgs[mod] }.uniq.compact
    end
  end
end