NestedLookup

Ruby library which enables key/value lookup, update, delete on deeply nested documents (Arrays and Hashes)Ruby library which enables key/value lookup, update, delete on deeply nested documents (Arrays and Hashes)

Features: (document might be Array of Hashes/Hash, Arrays/nested Arrays/nested Hashes etc)

1. (nested_lookup) key lookups on a deeply nested document. Returns an Array of matching Values.
2. (get_all_keys) Fetch all keys from a deeply nested document. Returns array of keys
3. (get_occurrence_of_key/get_occurrence_of_value) Returns the number of occurrences of a key/value from a deeply nested document
4. (nested_update) Given a document, find all occurences of the given key and update the value. By default, returns a copy of the document. To mutate the original use bang method (nested_update!)
5. (nested_delete) Given a document, find all occurrences of the given key and delete it. By default, returns a copy of the document. To mutate the original use bang method (nested_delete!)

Documents may be built out of nested Hashes and/or Arrays.

Installation

Add this line to your application's Gemfile:

gem 'nested_lookup'

And then execute:

$ bundle

Or install it yourself as:

$ gem install nested_lookup

Usage

quick tutorial

Rameshs-MacBook-Pro:nested_lookup rameshrv$ irb
irb(main):001:0> require 'nested_lookup'
=> true
irb(main):003:0> sample_data = {
irb(main):004:1*   "hardware_details": {
irb(main):005:2*     "model_name": 'MacBook Pro',
irb(main):006:2*     "processor_details": [
irb(main):007:3*       {
irb(main):008:4*         "processor_name": 'Intel Core i7',
irb(main):009:4*         "processor_speed": '2.7 GHz',
irb(main):010:4*         "core_details": {
irb(main):011:5*           "total_numberof_cores": '4',
irb(main):012:5*           "l2_cache(per_core)": '256 KB'
irb(main):013:5>         }
irb(main):014:4>       }
irb(main):015:3>     ],
irb(main):016:2*     "os_details": {
irb(main):017:3*       "product_version": '10.13.6',
irb(main):018:3*       "build_version": '17G65'
irb(main):019:3>     },
irb(main):020:2*     "memory": '16 GB'
irb(main):021:2>   },
irb(main):022:1*   "dup_hardware_details": {
irb(main):023:2*     "model_name": 'MacBook Pro - 1',
irb(main):024:2*     "os_details": {
irb(main):025:3*       "product_version": '10.14.0',
irb(main):026:3*       "build_version": '17G65'
irb(main):027:3>     },
irb(main):028:2*   }
irb(main):029:1> }
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>[{:processor_name=>"Intel Core i7", :processor_speed=>"2.7 GHz", :core_details=>{:total_numberof_cores=>"4", :"l2_cache(per_core)"=>"256 KB"}}], :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}, :dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}
irb(main):030:0>
irb(main):032:0>
irb(main):001:0>
# Search for key 'product_version'
irb(main):033:0* sample_data.nested_lookup('product_version')
=> ["10.13.6", "10.14.0"]
irb(main):001:0>
irb(main):001:0>
# Fetch all keys from the document
irb(main):034:0> sample_data.get_all_keys
=> ["hardware_details", "model_name", "processor_details", "processor_name", "processor_speed", "core_details", "total_numberof_cores", "l2_cache(per_core)", "os_details", "product_version", "build_version", "memory", "dup_hardware_details", "model_name", "os_details", "product_version", "build_version"]
irb(main):001:0>
irb(main):001:0>
# Get occurrence of key 'model_name' (present in both 'hardware_details', 'dup_hardware_details')
irb(main):035:0> sample_data.get_occurrence_of_key('model_name')
=> 2
irb(main):001:0>
irb(main):001:0>
# Get occurrence of value 'memory' (It is actually a key, should return 0)
irb(main):036:0> sample_data.get_occurrence_of_value('memory')
=> 0
irb(main):001:0>
irb(main):001:0>
# Get occurrence of value 'Intel Core i7'
irb(main):037:0> sample_data.get_occurrence_of_value('Intel Core i7')
=> 1
irb(main):001:0>
irb(main):001:0>
# Get value for the key 'memory', 'l2_cache(per_core)'
irb(main):032:0* sample_data.nested_get('memory')
=> "16 GB"
irb(main):033:0> sample_data.nested_get('l2_cache(per_core)')
=> "256 KB"
irb(main):001:0>
irb(main):001:0>
# Delete a key in nested document (key -> 'hardware_details')
irb(main):034:0> sample_data.nested_delete('hardware_details')
=> {:dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}
irb(main):001:0>
irb(main):001:0>
# Update a key in nested document (key -> 'hardware_details')
irb(main):035:0> sample_data.nested_update(key: 'hardware_details', value: 'Test')
=> {:hardware_details=>"Test", :dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}
irb(main):036:0>

longer tutorial

You may control the nested_lookup method's behavior by passing some optional arguments.

1. wild (defaults to False):

• if wild is True, treat the given key as a case insensitive substring when performing lookups.

2. with_keys (defaults to False):

• if with_keys is True, return a Hash of all matched keys and an Array of values.

For example, given the following document:

sample_data = {
  "hardware_details": {
    "model_name": 'MacBook Pro',
    "processor_details": [
      {
        "processor_name": 'Intel Core i7',
        "processor_speed": '2.7 GHz',
        "core_details": {
          "total_numberof_cores": '4',
          "l2_cache(per_core)": '256 KB'
        }
      }
    ],
    "os_details": {
      "product_version": '10.13.6',
      "build_version": '17G65'
    },
    "memory": '16 GB'
  }
}

We could act wild and find all the version like this:

irb(main):069:0* sample_data.nested_lookup('version', wild: true)
=> ["10.13.6", "17G65"]
irb(main):072:0>

Additionally, if you also needed the matched key names, you could do this:

irb(main):071:0* sample_data.nested_lookup('version', wild: true, with_keys: true)
=> {"product_version"=>["10.13.6"], "build_version"=>["17G65"]}
irb(main):073:0* sample_data.nested_lookup('product_version', with_keys: true)
=> {"product_version"=>["10.13.6"]}
irb(main):074:0> 

To get a list of every nested key in a document, run this:

irb(main):060:0* require 'nested_lookup'
=> false
irb(main):061:0> include NestedLookup
=> Object
irb(main):062:0> sample_data.get_all_keys
=> ["hardware_details", "model_name", "processor_details", "processor_name", "processor_speed", "core_details", "total_numberof_cores", "l2_cache(per_core)", "os_details", "product_version", "build_version", "memory"]
irb(main):063:0> 

To get the number of occurrence of the given key/value

irb(main):060:0* require 'nested_lookup'
=> false
irb(main):061:0> include NestedLookup
=> Object
irb(main):064:0* sample_data.get_occurrence_of_key('processor_speed')
=> 1
irb(main):065:0> sample_data.get_occurrence_of_value('256 KB')
=> 1
irb(main):072:0>

To Get / Delete / Update a key->value pair in a nested document

irb(main):001:0> require 'nested_lookup'
=> true
irb(main):066:0* sample_data.nested_get('os_details')
=> {:product_version=>"10.13.6", :build_version=>"17G65"}
irb(main):067:0> sample_data.nested_get('memory')
=> "16 GB"
irb(main):068:0> sample_data.nested_delete('processor_details')
=> {:hardware_details=>{:model_name=>"MacBook Pro", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}}
irb(main):069:0> sample_data.nested_update(key: 'processor_details', value: 'Test')
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>"Test", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}}
irb(main):070:0>

Delete key->value pair (Normal and bang menthod)

# Normal method (Returns a document that includes everything but the given key)
irb(main):068:0> sample_data.nested_delete('processor_details')
=> {:hardware_details=>{:model_name=>"MacBook Pro", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}}
irb(main):071:0* sample_data
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>[{:processor_name=>"Intel Core i7", :processor_speed=>"2.7 GHz", :core_details=>{:total_numberof_cores=>"4", :"l2_cache(per_core)"=>"256 KB"}}], :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}}
# Bang method (Replaces the document without the given key)
irb(main):074:0* sample_data.nested_delete!('processor_details')
=> {:hardware_details=>{:model_name=>"MacBook Pro", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}}
irb(main):075:0> sample_data
=> {:hardware_details=>{:model_name=>"MacBook Pro", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}}

Update value for the given key (Normal and bang method)

# Normal method (Returns a document that has updated key, value pair)
irb(main):109:0* sample_data.nested_update(key: 'processor_details', value: 'Test')
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>"Test", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}, :dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}
irb(main):110:0> sample_data
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>[{:processor_name=>"Intel Core i7", :processor_speed=>"2.7 GHz", :core_details=>{:total_numberof_cores=>"4", :"l2_cache(per_core)"=>"256 KB"}}], :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}, :dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}
# Replaces the document with the updated key, value pair
irb(main):114:0* sample_data.nested_update!(key: 'processor_details', value: 'Test')
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>"Test", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}, :dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}
irb(main):115:0> sample_data
=> {:hardware_details=>{:model_name=>"MacBook Pro", :processor_details=>"Test", :os_details=>{:product_version=>"10.13.6", :build_version=>"17G65"}, :memory=>"16 GB"}, :dup_hardware_details=>{:model_name=>"MacBook Pro - 1", :os_details=>{:product_version=>"10.14.0", :build_version=>"17G65"}}}

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec 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.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/rameshrvr/nested_lookup. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the NestedLookup project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.