Modeling complex JSON in Ruby - ruby

Question

I have a piece of JSON that is the boxscore of an NBA game as in an example below. Are there any strategies to turn these data into a sane Ruby model (maybe using serializers)? When I pull in these data from a remote API, there are lots of nested data within this JSON such as the Individual Player statistics, Team Statistics, team data, etc. Any solution on tools to use to deal with this JSON with sane Ruby modeling is preferred. Shouldn't matter but I'll be trying to work this modeling into a ruby gem, not a rails app.
Here's an example of one JSON blob I'm dealing with:
[
{
"game_length": "2:38",
"location": "Sleep Train Arena",
"game_time": "10:00 PM",
"season_type": "Regular",
"game_id": 19123,
"scores_by_quarter": [
{
"scores": {
"quarter": "1",
"away_team_score": 23,
"home_team_score": 24
}
},
{
"scores": {
"quarter": "2",
"away_team_score": 27,
"home_team_score": 21
}
},
{
"scores": {
"quarter": "3",
"away_team_score": 23,
"home_team_score": 27
}
},
{
"scores": {
"quarter": "4",
"away_team_score": 21,
"home_team_score": 22
}
},
{
"scores": {
"quarter": "OT",
"away_team_score": 10,
"home_team_score": 4
}
}
],
"team_stats": [
{
"team": {
"team_id": 101,
"team_name": "LA Clippers",
"listings": [
{
"listing": {
"freethrows_attempted": 2,
"freethrows_made": 0,
"field_goals_attempted": 5,
"turnovers": 1,
"total_rebounds": 3,
"blocks": 0,
"steals": 1,
"assists": 1,
"field_goals_made": 2,
"offensive_rebounds": 1,
"player_first_name": "Jared",
"three_points_made": 1,
"player_last_name": "Dudley",
"points": 5,
"personal_fouls": 4,
"three_points_attempted": 3,
"minutes_played": 37,
"technical_fouls": 0,
"player_position": "F",
"player_id": 1292,
"started": "Yes",
"seconds_played": 16,
"defensive_rebounds": 2
}
},
{
"listing": {
"freethrows_attempted": 10,
"freethrows_made": 7,
"field_goals_attempted": 15,
"turnovers": 4,
"total_rebounds": 12,
"blocks": 0,
"steals": 0,
"assists": 1,
"field_goals_made": 7,
"offensive_rebounds": 2,
"player_first_name": "Blake",
"three_points_made": 0,
"player_last_name": "Griffin",
"points": 21,
"personal_fouls": 4,
"three_points_attempted": 0,
"minutes_played": 38,
"technical_fouls": 1,
"player_position": "F",
"player_id": 1590,
"started": "Yes",
"seconds_played": 57,
"defensive_rebounds": 10
}
},
{
"listing": {
"freethrows_attempted": 5,
"freethrows_made": 0,
"field_goals_attempted": 9,
"turnovers": 1,
"total_rebounds": 15,
"blocks": 9,
"steals": 0,
"assists": 2,
"field_goals_made": 5,
"offensive_rebounds": 6,
"player_first_name": "DeAndre",
"three_points_made": 0,
"player_last_name": "Jordan",
"points": 10,
"personal_fouls": 1,
"three_points_attempted": 0,
"minutes_played": 40,
"technical_fouls": 0,
"player_position": "C",
"player_id": 1487,
"started": "Yes",
"seconds_played": 14,
"defensive_rebounds": 9
}
},
{
"listing": {
"freethrows_attempted": 4,
"freethrows_made": 4,
"field_goals_attempted": 9,
"turnovers": 1,
"total_rebounds": 1,
"blocks": 0,
"steals": 1,
"assists": 2,
"field_goals_made": 4,
"offensive_rebounds": 0,
"player_first_name": "J.J.",
"three_points_made": 1,
"player_last_name": "Redick",
"points": 13,
"personal_fouls": 2,
"three_points_attempted": 4,
"minutes_played": 16,
"technical_fouls": 0,
"player_position": "G",
"player_id": 1129,
"started": "Yes",
"seconds_played": 59,
"defensive_rebounds": 1
}
},
{
"listing": {
"freethrows_attempted": 4,
"freethrows_made": 4,
"field_goals_attempted": 12,
"turnovers": 1,
"total_rebounds": 1,
"blocks": 0,
"steals": 1,
"assists": 2,
"field_goals_made": 5,
"offensive_rebounds": 0,
"player_first_name": "Darren",
"three_points_made": 1,
"player_last_name": "Collison",
"points": 15,
"personal_fouls": 1,
"three_points_attempted": 2,
"minutes_played": 40,
"technical_fouls": 0,
"player_position": "G",
"player_id": 1578,
"started": "Yes",
"seconds_played": 7,
"defensive_rebounds": 1
}
},
{
"listing": {
"freethrows_attempted": 4,
"freethrows_made": 4,
"field_goals_attempted": 22,
"turnovers": 2,
"total_rebounds": 7,
"blocks": 0,
"steals": 0,
"assists": 11,
"field_goals_made": 12,
"offensive_rebounds": 2,
"player_first_name": "Jamal",
"three_points_made": 3,
"player_last_name": "Crawford",
"points": 31,
"personal_fouls": 1,
"three_points_attempted": 7,
"minutes_played": 37,
"technical_fouls": 0,
"player_position": "G",
"player_id": 299,
"started": "No",
"seconds_played": 29,
"defensive_rebounds": 5
}
},
{
"listing": {
"freethrows_attempted": 4,
"freethrows_made": 3,
"field_goals_attempted": 5,
"turnovers": 2,
"total_rebounds": 5,
"blocks": 0,
"steals": 1,
"assists": 1,
"field_goals_made": 1,
"offensive_rebounds": 1,
"player_first_name": "Antawn",
"three_points_made": 0,
"player_last_name": "Jamison",
"points": 5,
"personal_fouls": 1,
"three_points_attempted": 0,
"minutes_played": 16,
"technical_fouls": 0,
"player_position": "F",
"player_id": 682,
"started": "No",
"seconds_played": 37,
"defensive_rebounds": 4
}
},
{
"listing": {
"freethrows_attempted": 2,
"freethrows_made": 1,
"field_goals_attempted": 1,
"turnovers": 0,
"total_rebounds": 0,
"blocks": 0,
"steals": 0,
"assists": 0,
"field_goals_made": 1,
"offensive_rebounds": 0,
"player_first_name": "Ryan",
"three_points_made": 0,
"player_last_name": "Hollins",
"points": 3,
"personal_fouls": 2,
"three_points_attempted": 0,
"minutes_played": 10,
"technical_fouls": 0,
"player_position": "C",
"player_id": 1198,
"started": "No",
"seconds_played": 11,
"defensive_rebounds": 0
}
},
{
"listing": {
"freethrows_attempted": 2,
"freethrows_made": 1,
"field_goals_attempted": 4,
"turnovers": 0,
"total_rebounds": 1,
"blocks": 0,
"steals": 0,
"assists": 0,
"field_goals_made": 0,
"offensive_rebounds": 1,
"player_first_name": "Reggie",
"three_points_made": 0,
"player_last_name": "Bullock",
"points": 1,
"personal_fouls": 0,
"three_points_attempted": 3,
"minutes_played": 12,
"technical_fouls": 0,
"player_position": "F",
"player_id": 2408,
"started": "No",
"seconds_played": 3,
"defensive_rebounds": 0
}
},
{
"listing": {
"freethrows_attempted": 0,
"freethrows_made": 0,
"field_goals_attempted": 1,
"turnovers": 0,
"total_rebounds": 1,
"blocks": 0,
"steals": 0,
"assists": 0,
"field_goals_made": 0,
"offensive_rebounds": 0,
"player_first_name": "Willie",
"three_points_made": 0,
"player_last_name": "Green",
"points": 0,
"personal_fouls": 0,
"three_points_attempted": 1,
"minutes_played": 15,
"technical_fouls": 0,
"player_position": "G",
"player_id": 634,
"started": "No",
"seconds_played": 7,
"defensive_rebounds": 1
}
},
{
"listing": {
"player_first_name": "Chris",
"reason": "Coach's Decision",
"player_last_name": "Paul",
"status": "Did Not Play",
"player_id": 1011
}
},
{
"listing": {
"player_first_name": "Matt",
"reason": "Coach's Decision",
"player_last_name": "Barnes",
"status": "Did Not Play",
"player_id": 827
}
},
{
"listing": {
"player_first_name": "Byron",
"reason": "Coach's Decision",
"player_last_name": "Mullens",
"status": "Did Not Play",
"player_id": 1568
}
},
{
"listing": {
"player_first_name": "Maalik",
"reason": "Injured",
"player_last_name": "Wayns",
"status": "Did Not Play",
"player_id": 2344
}
}
],
"totals": {
"freethrows_attempted": 37,
"freethrows_made": 24,
"field_goals_attempted": 83,
"total_rebounds": 46,
"points_off_turnovers": 18,
"blocks": 9,
"illegal_defense": 1,
"steals": 4,
"assists": 20,
"field_goals_made": 37,
"turnoveres": 12,
"offensive_rebounds": 13,
"team_turnovers": 12,
"three_points_made": 6,
"team_rebounds": 14,
"shooting_percentages": {
"field_goal_percentage": 0.446,
"three_point_percentage": 0.3,
"freethrow_percentage": 0.649
},
"points": 104,
"personal_fouls": 16,
"three_points_attempted": 20,
"minutes_played": 265,
"technical_fouls": 2,
"seconds_played": 240,
"non_player_technicals": 0,
"defensive_rebounds": 33
}
}
},
{
"team": {
"team_id": 109,
"team_name": "Sacramento",
"listings": [
{
"listing": {
"freethrows_attempted": 1,
"freethrows_made": 0,
"field_goals_attempted": 13,
"turnovers": 1,
"total_rebounds": 6,
"blocks": 0,
"steals": 0,
"assists": 4,
"field_goals_made": 6,
"offensive_rebounds": 0,
"player_first_name": "Derrick",
"three_points_made": 0,
"player_last_name": "Williams",
"points": 12,
"personal_fouls": 3,
"three_points_attempted": 2,
"minutes_played": 32,
"technical_fouls": 0,
"player_position": "F",
"player_id": 2192,
"started": "Yes",
"seconds_played": 21,
"defensive_rebounds": 6
}
},
{
"listing": {
"freethrows_attempted": 0,
"freethrows_made": 0,
"field_goals_attempted": 7,
"turnovers": 1,
"total_rebounds": 4,
"blocks": 1,
"steals": 0,
"assists": 0,
"field_goals_made": 3,
"offensive_rebounds": 2,
"player_first_name": "Jason",
"three_points_made": 0,
"player_last_name": "Thompson",
"points": 6,
"personal_fouls": 4,
"three_points_attempted": 0,
"minutes_played": 23,
"technical_fouls": 0,
"player_position": "F",
"player_id": 1496,
"started": "Yes",
"seconds_played": 11,
"defensive_rebounds": 2
}
},
{
"listing": {
"freethrows_attempted": 3,
"freethrows_made": 3,
"field_goals_attempted": 19,
"turnovers": 3,
"total_rebounds": 9,
"blocks": 3,
"steals": 0,
"assists": 6,
"field_goals_made": 11,
"offensive_rebounds": 1,
"player_first_name": "DeMarcus",
"three_points_made": 0,
"player_last_name": "Cousins",
"points": 25,
"personal_fouls": 5,
"three_points_attempted": 0,
"minutes_played": 41,
"technical_fouls": 0,
"player_position": "C",
"player_id": 1900,
"started": "Yes",
"seconds_played": 21,
"defensive_rebounds": 8
}
},
{
"listing": {
"freethrows_attempted": 3,
"freethrows_made": 3,
"field_goals_attempted": 12,
"turnovers": 2,
"total_rebounds": 4,
"blocks": 0,
"steals": 2,
"assists": 3,
"field_goals_made": 5,
"offensive_rebounds": 2,
"player_first_name": "Ben",
"three_points_made": 1,
"player_last_name": "McLemore",
"points": 14,
"personal_fouls": 3,
"three_points_attempted": 6,
"minutes_played": 34,
"technical_fouls": 0,
"player_position": "G",
"player_id": 2432,
"started": "Yes",
"seconds_played": 43,
"defensive_rebounds": 2
}
},
{
"listing": {
"freethrows_attempted": 1,
"freethrows_made": 1,
"field_goals_attempted": 12,
"turnovers": 0,
"total_rebounds": 3,
"blocks": 0,
"steals": 0,
"assists": 7,
"field_goals_made": 4,
"offensive_rebounds": 1,
"player_first_name": "Greivis",
"three_points_made": 2,
"player_last_name": "Vasquez",
"points": 11,
"personal_fouls": 2,
"three_points_attempted": 6,
"minutes_played": 35,
"technical_fouls": 0,
"player_position": "G",
"player_id": 1970,
"started": "Yes",
"seconds_played": 58,
"defensive_rebounds": 2
}
},
{
"listing": {
"freethrows_attempted": 0,
"freethrows_made": 0,
"field_goals_attempted": 4,
"turnovers": 1,
"total_rebounds": 3,
"blocks": 0,
"steals": 0,
"assists": 0,
"field_goals_made": 2,
"offensive_rebounds": 1,
"player_first_name": "Marcus",
"three_points_made": 0,
"player_last_name": "Thornton",
"points": 4,
"personal_fouls": 5,
"three_points_attempted": 2,
"minutes_played": 17,
"technical_fouls": 0,
"player_position": "G",
"player_id": 1646,
"started": "No",
"seconds_played": 26,
"defensive_rebounds": 2
}
},
{
"listing": {
"freethrows_attempted": 2,
"freethrows_made": 1,
"field_goals_attempted": 5,
"turnovers": 1,
"total_rebounds": 9,
"blocks": 0,
"steals": 0,
"assists": 0,
"field_goals_made": 3,
"offensive_rebounds": 3,
"player_first_name": "Patrick",
"three_points_made": 0,
"player_last_name": "Patterson",
"points": 7,
"personal_fouls": 4,
"three_points_attempted": 0,
"minutes_played": 26,
"technical_fouls": 0,
"player_position": "F",
"player_id": 1950,
"started": "No",
"seconds_played": 59,
"defensive_rebounds": 6
}
},
{
"listing": {
"freethrows_attempted": 0,
"freethrows_made": 0,
"field_goals_attempted": 1,
"turnovers": 2,
"total_rebounds": 1,
"blocks": 0,
"steals": 0,
"assists": 0,
"field_goals_made": 0,
"offensive_rebounds": 1,
"player_first_name": "Hamady",
"three_points_made": 0,
"player_last_name": "N`diaye",
"points": 0,
"personal_fouls": 3,
"three_points_attempted": 0,
"minutes_played": 4,
"technical_fouls": 0,
"player_position": "C",
"player_id": 1944,
"started": "No",
"seconds_played": 56,
"defensive_rebounds": 0
}
},
{
"listing": {
"freethrows_attempted": 0,
"freethrows_made": 0,
"field_goals_attempted": 2,
"turnovers": 0,
"total_rebounds": 0,
"blocks": 0,
"steals": 1,
"assists": 1,
"field_goals_made": 0,
"offensive_rebounds": 0,
"player_first_name": "Travis",
"three_points_made": 0,
"player_last_name": "Outlaw",
"points": 0,
"personal_fouls": 0,
"three_points_attempted": 1,
"minutes_played": 9,
"technical_fouls": 0,
"player_position": "F",
"player_id": 759,
"started": "No",
"seconds_played": 30,
"defensive_rebounds": 0
}
},
{
"listing": {
"player_first_name": "Chuck",
"reason": "Coach's Decision",
"player_last_name": "Hayes",
"status": "Did Not Play",
"player_id": 1044
}
},
{
"listing": {
"player_first_name": "Carl",
"reason": "Injured",
"player_last_name": "Landry",
"status": "Did Not Play",
"player_id": 1333
}
},
{
"listing": {
"player_first_name": "Ray",
"reason": "Injured",
"player_last_name": "McCallum",
"status": "Did Not Play",
"player_id": 2430
}
},
{
"listing": {
"player_first_name": "Jimmer",
"reason": "Coach's Decision",
"player_last_name": "Fredette",
"status": "Did Not Play",
"player_id": 2111
}
}
],
"totals": {
"freethrows_attempted": 10,
"freethrows_made": 8,
"field_goals_attempted": 91,
"total_rebounds": 44,
"points_off_turnovers": 15,
"blocks": 5,
"illegal_defense": 1,
"steals": 4,
"assists": 24,
"field_goals_made": 42,
"turnoveres": 15,
"offensive_rebounds": 12,
"team_turnovers": 16,
"three_points_made": 6,
"team_rebounds": 6,
"shooting_percentages": {
"field_goal_percentage": 0.462,
"three_point_percentage": 0.261,
"freethrow_percentage": 0.8
},
"points": 98,
"personal_fouls": 33,
"three_points_attempted": 23,
"minutes_played": 265,
"technical_fouls": 1,
"seconds_played": 360,
"non_player_technicals": 0,
"defensive_rebounds": 32
}
}
}
],
"away_team_final_score": 104,
"quarter": 5,
"game_date": "November 29, 2013",
"technicals": [
{
"listing": {
"flagrant": "False",
"team_id": 109,
"time_left": "8:40",
"player_first_name": "",
"quarter": 3,
"player_last_name": "",
"player_id": 0,
"def_3_sec": "True",
"bench": "False"
}
},
{
"listing": {
"flagrant": "False",
"team_id": 101,
"time_left": "6:11",
"player_first_name": "Blake",
"quarter": 3,
"player_last_name": "Griffin",
"player_id": 1590,
"def_3_sec": "False",
"bench": "False"
}
},
{
"listing": {
"flagrant": "False",
"team_id": 101,
"time_left": "5:46",
"player_first_name": "",
"quarter": 3,
"player_last_name": "",
"player_id": 0,
"def_3_sec": "True",
"bench": "False"
}
}
],
"sport": "NBA",
"visiting_team": "LA Clippers",
"status": "FINAL",
"home_team_id": 109,
"title": "LA Clippers at Sacramento",
"attendance": "17317",
"home_team_final_score": 98,
"updated_at": "2013-11-30 06:08:40 UTC",
"visiting_team_id": 101,
"home_team": "Sacramento",
"season_year": "2013",
"officials": "Tony Brothers, David Guthrie, JT Orr"
}
]

Answer 1

You can parse JSON data into two classes, Arrays and Hashes:
Arrays:
data = [1, 2]
data.to_json # => "[1,2]"
JSON.parse(data.to_json) # => [1, 2]
Hashes:
data = {'a' => 1}
data.to_json # => "{\"a\":1}"
JSON.parse(data.to_json) # => {"a"=>1}
Attempting to generate anything else results in an error.
Once you parse the JSON string back into a Ruby object, you'll have one of those two types acting as a wrapper or container for the data you want, so you can use normal Ruby loops to walk through the data if it's an Array, and directly access the values you want if it's a Hash.
While your sample appears complex to you, it can easily be broken down into some simple code that will extract the data. If I parse the data and store it in a variable called data:
data.first returns the hash containing the data, which, in your example is all the data. If there were multiple hashes then iterate over them using:
data.each { |hash| ... }
or:
data.map { |hash| ... }
Once you have a sub-hash you can access things in similar manners, by iterating or using hash accesses:
data.first['scores_by_quarter'].last['scores']['home_team_score']
# => 4

Answer 2

I had to copy your JSON into a file to be able to read it properly(note that this is not necessary, you can supply the JSON stream directly to JSON.parse as it should be properly formatted), then parse it as a JSON to an array of hashes and use OpenStruct to convert them to ruby objects, if you have a large array, then OpenStruct is not very good with performance, explanation can be found here
require 'ostruct'
require 'json'
a = JSON.parse(File.read('temp.json'))
a.map! { |team| OpenStruct.new(team) }
Setters and getters generated by OpenStruct
a.each { |x| p x.methods(false) };
[:game_length, :game_length=, :location, :location=, :game_time, :game_time=, :season_type, :season_type=, :game_id, :game_id=, :scores_by_quarter, :scores_by_quarter=, :team_stats, :team_stats=, :away_team_final_score, :away_team_final_score=, :quarter, :quarter=, :game_date, :game_date=, :technicals, :technicals=, :sport, :sport=, :visiting_team, :visiting_team=, :status, :status=, :home_team_id, :home_team_id=, :title, :title=, :attendance, :attendance=, :home_team_final_score, :home_team_final_score=, :updated_at, :updated_at=, :visiting_team_id, :visiting_team_id=, :home_team, :home_team=, :season_year, :season_year=, :officials, :officials=]