Question

I have two json files that I’m trying to merge. The JSONs have different formatting (see below). I’d like to merge records, so [0] from file one and [0] from file two would become one record [0] in the new merged file.

The first JSON (file_a.json), appears like so:

{

    "query": {
        "count": 4,
        "created": "2012-11-21T23:07:00Z",
        "lang": "en-US",
        "results": {
            "quote": [
                {
                    "Name": "Bill",
                    "Age": "46",
                    "Number": "3.55"
                },
                {
                    "Name": "Jane",
                    "Age": "33",
                    "Number": nil
                },
                {
                    "Name": "Jack",
                    "Age": "55",
                    "Number": nil
                },
                {
                    "Name": "Xavier",
                    "Age": nil,
                    "Number": "153353535"
                }
            ]
        }
    }

}

The second JSON (file_b.json) appears like so:

[

    {
        "Number2": 25253,
        "Number3": 435574,
        "NAME": "Bill"
    },
    {
        "Number2": 345353,
        "Number3": 5566,
        "NAME": "Jane"
    },
    {
        "Number2": 56756,
        "Number3": 232435,
        "NAME": "Jack"
    },
    {
        "Number2": 7457,
        "Number3": 45425,
        "NAME": "Xavier"
    }
]

None of the keys are the same in both JSONs (well, actually “Name” is a key in both, but in the first the key is “Name” and in the second its “NAME” – just so I can check that the merge works correctly – so I want “Name” and “NAME” in the final JSON), the first record in the first file matches with the first record in the second file, and so on.

So far, I tried merging like this:

merged = %w[a b].inject([]) { |m,f| m << JSON.parse(File.read("file_#{f}.json")) }.flatten

But this of course merged them, but not how I wanted them merged (they are merged sucessively, and because of the different formatting, it gets quite ugly).

I also tried merging like this:

a = JSON.parse(File.read("file_a.json"))
b = JSON.parse(File.read("file_b.json"))

merged = a.zip(b)

Came closer but still not correct and the formatting was still horrendous.

In the end, what I want is this (formatting of second JSON – headers from first JSON can be junked):

[

    {
        "Name": "Bill",
        "Age": 46,
        "Number": 3.55,
        "Number2": 25253,
        "Number3": 435574,
        "NAME": "Bill"
    },
    {
        "Name": "Jane",
        "Age": 33,
        "Number": nil,
        "Number2": 345353,
        "Number3": 5566,
        "NAME": "Jane"
    },
    {
        "Name": "Jack",
        "Age": 55,
        "Number": nil,
        "Number2": 56756,
        "Number3": 232435,
        "NAME": "Jack"
    },
    {
        "Name": "Xavier",
        "Age": nil,
        "Number": 153353535,
        "Number2": 7457,
        "Number3": 45425,
        "NAME": "Xavier"
    }
]

Any help is appreciated. Thanks a lot.

Answer 1

Hеllo, seems format changed from last time 🙂

UPDATE: more readable version that also convert corresponding values to integers/floats:

require 'json'
require 'ap'

a = JSON.parse(File.read('./a.json'))['query']['results']['quote'] rescue []
b = JSON.parse(File.read('./b.json'))

final = []
a.each_with_index do |ah,i|
  unless bh = b[i]
    bh = {}
    puts "seems b has no #{i} key, merging skipped"
  end

  final << ah.merge(bh).inject({}) do |f, (k,v)|
    if v.is_a?(String)
      if v =~ /\A\d+\.\d+\Z/
        v = v.to_f
      elsif v =~ /\A\d+\Z/
        v = v.to_i
      end
    end
    f.update k => v
  end
end
ap final

will display:

[
  [0] {
       "Name" => "Bill",
      "Age" => 46,
     "Number" => 3.55,
    "Number2" => 25253,
    "Number3" => 435574,
       "NAME" => "Bill"
  },
  [1] {
       "Name" => "Jane",
      "Age" => 33,
     "Number" => nil,
    "Number2" => 345353,
    "Number3" => 5566,
       "NAME" => "Jane"
  },
  [2] {
       "Name" => "Jack",
      "Age" => 55,
     "Number" => nil,
    "Number2" => 56756,
    "Number3" => 232435,
       "NAME" => "Jack"
  },
  [3] {
       "Name" => "Xavier",
      "Age" => nil,
     "Number" => 153353535,
    "Number2" => 7457,
    "Number3" => 45425,
       "NAME" => "Xavier"
  }
]

Here is a working demo

Btw, your json is a bit wrong in both files.

See the fixed versions here and here