FieldMask Parser. If you want to know more about FieldMask, please see https://developers.google.com/protocol-buffers/docs/reference/google.protobuf#fieldmask .
Add this line to your application's Gemfile:
gem 'fmparser'And then execute:
$ bundle
Or install it yourself as:
$ gem install fmparser
FMParser.parse parses FieldMask parameter and returns a FMParser::MessageNode object.
For example, suppose you have the protobuf message classes shown below:
syntax = "proto3";
package msg;
message User {
Operation op = 1;
int64 id = 2;
repeated Name names =3;
Job job = 4;
}
message Name {
Operation op = 1;
int64 id = 2;
string first_name = 3;
string middle_name = 4;
string last_name = 5;
string language = 6;
}
message Job {
Operation op = 1;
int64 id = 2;
string company = 3;
}
enum Operation {
OPERATION_UNSPECIFIED = 0;
CREATE = 1;
UPDATE = 2;
DELETE = 3;
}Then, you can parse paths array of strings with root protobuf message class.
[1] pry(main)> f = FMParser.parse(paths: ["op", "id", "names.first_name", "names.last_name"], root: Msg::User)
=> #<FMParser::MessageNode:0x00007f7fc9848168
@enums=[#<FMParser::EnumNode:0x00007f7fc98489b0 @label=:optional, @name=:op, @type=Msg::Operation>],
@label=nil,
@messages=
[#<FMParser::MessageNode:0x00007f7fc9848208
@enums=[],
@label=:repeated,
@messages=[],
@name=:names,
@scalars=
[#<FMParser::ScalarNode:0x00007f7fc98484b0 @label=:optional, @name=:first_name, @type=:string>,
#<FMParser::ScalarNode:0x00007f7fc98482a8 @label=:optional, @name=:last_name, @type=:string>],
@type=Msg::Name>],
@name=nil,
@scalars=[#<FMParser::ScalarNode:0x00007f7fc9848820 @label=:optional, @name=:id, @type=:int64>],
@type=Msg::User>
[2] pry(main)> f.field_names
=> [:id, :op, :names]
[3] pry(main)> f.has?(:id)
=> true
[4] pry(main)> f.has?(:names)
=> true
[5] pry(main)> f.has?(:job)
=> false
[6] pry(main)> f.get_child(:names)
=> #<FMParser::MessageNode:0x00007f7fc9848208
@enums=[],
@label=:repeated,
@messages=[],
@name=:names,
@scalars=
[#<FMParser::ScalarNode:0x00007f7fc98484b0 @label=:optional, @name=:first_name, @type=:string>,
#<FMParser::ScalarNode:0x00007f7fc98482a8 @label=:optional, @name=:last_name, @type=:string>],
@type=Msg::Name>
[7] pry(main)> f.get_child(:names).field_names
=> [:first_name, :last_name]After checking out the repo, run bin/setup to install dependencies. Then, run bundle exec rspec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.
Bug reports and pull requests are welcome on GitHub at https://github.com/wantedly/fmparser.
The gem is available as open source under the terms of the MIT License.