Ruby-On-Rails Authors: Liz McMillan, Pat Romanski, Elizabeth White, Hovhannes Avoyan, Yeshim Deniz

Related Topics: Ruby-On-Rails, Open Source Cloud

Ruby-On-Rails: Blog Feed Post

How to Generate Boxscores with Ruby from Live MLB Data

As an avid baseball fan, I’ve always been interested in the statistics that surround baseball

As an avid baseball fan, I’ve always been interested in the statistics that surround baseball. More so than in any other sport, baseball is a game ruled by statistics. In this post, I will describe a program that I wrote in the Ruby language to generate box scores for any Major Leage Baseball(MLB) game by using the live XML data provided by MLB. Ruby makes it easy to do using plain Ruby along with just a few libraries.

Live MLB Data
The amount of raw data that MLB makes available is extensive. It includes all of the traditional boxscore statistics plus deep detail on every pitch thrown including its velocity, movement, and location. If you have ever used the Gameday baseball game watcher application than you’ve indirectly been a consumer of this data. All of the data that powers the Gameday application is made available on an MLB server as raw XML files. Also, this is not just historical data. The data is real-time and updated with every pitch thrown during live games. You also have historical data available to you. The data goes back to the 1926 season.

Building a boxscore template with ERb
For those not familiar with ERb, it is a templating engine that allows you to embed Ruby code inside of a document. The Ruby code can then be evaluated at run time and merged with the rest of the document to form a new document. The Rails framework uses ERb to generate HTML content from templates. For the boxscore generator, I used an ERb template to format the layout of the boxscore. This allowed me to keep the presentation seperate from the logic layers of the application. Most Ruby developers are familiar with the ERb templating engine from its usage in Ruby on Rails applications. However, not all developers are aware that ERb can be used very easily outside of a Rails application. ERb is in no way tightly coupled to the Rails framework. ERb is normally included with the standard Ruby distribution. You can use ERb templates by simply requiring ‘erb’ in your Ruby application.

Here is an example of ERb taken from my boxscore template. This section is used to display the linescore of a game:

<div id="linescore">
  <label><%= cities[0] %></label>
  <% (0..8).each do |num| %>
    <%= innings[num][0] %>
  <% end %>
  &nbsp;<b><%= tots[0][0] + '  ' + tots[0][1] + '  ' + tots[0][2] %></b>
  <label><%= cities[1] %></label>
  <% (0..8).each do |num| %>
    <%= innings[num][1] %>
  <% end %>
  &nbsp;<b><%= tots[1][0] + '  ' + tots[1][1] + '  ' + tots[1][2] %></b>

At the bottom of this post you can find links to download the complete source code for this project including the full boxscore ERb template.

Steps to generate a boxscore
Now that you know about the MLB data source, and ERb, I’ll describe the steps that are used to generate a boxscore in a Ruby application.

  • Find the correct Gameday ID for the game you are interested in.
  • Retreive the correct boxscore.xml file from gd2.mlb.com
  • Parse the boxscore XML to pull out relevant data.
  • Merge the data into the boxscore template and save the result.

The sections below describe each of these steps in more detail.

Find the correct Gameday ID for the game you are interested in

Each MLB game can be identified on the gameday server with a gameday ID. The gameday ID is a string that contains the date of the game concatenated with team information. A gameday ID has the following format:


Finding the gameday ID for a game you are interested in is done by looking at the subdirectories contained in a directory that corresponds to the game date you are looking for. That directory will contain a subdirectory for each game played on that date. The game ID can be parsed from the name of that game’s subdirectory. For example, if you were interested in the Detroit Tigers game played on June 6, 2009, you would scan through the subdirectories contained in this directotry:


Within that directory, you would find a subdirectory named:


and from that you can find the game id by stripping off the leading ‘gid_’ from the directory name.

Retreive the correct boxscore.xml file from gd2.mlb.com
After you have identified the correct gameday ID, you have to make an HTTP call to retrieve the boxscore.xml file from the gd2.mlb.com server. This is a fairly simple task in Ruby done using the Net::HTTP library.

I have defined a constant to represent the root path for the gameday server.

GD2_MLB_BASE = "http://gd2.mlb.com/components/game"

Below is the ruby code used to retrieve the boxscore.xml file.

def get_boxscore(year, month, day, gid)
  url = "#{GD2_MLB_BASE}/mlb/year_" + year +
             "/month_" + month + "/day_" + day +
  xml_data = Net::HTTP.get_response(URI.parse(url)).body
  return xml_data

Parse the boxscore XML to pull out relevant data
Now that you have the boxscore.xml file, the next thing that you’ll want to do is parse this file to pull out data that you’ll want to use in your formatted boxscore. There are several XML parsing libraries available for ruby. I chose to use the REXML library to do this parsing. REXML is easy to work with and made the task relatively simple to code. In the sample shown below, I am parsing the boxscore XML file to find all of the batter statistics and pushing those into an array of batters. I will then use that array of batters from my boxscore ERb template to display the batters section of the boxscore.

# Returns an array of hashes where each hash holds data
# for a batter whom appeared in the game.  Specify either
# home or away team batters.
def get_batters(home_or_away)
  doc = REXML::Document.new(@xml_data)
  batters = []
    { |element|
      batter = {}
      batter['name'] = element.attributes['name']
      batter['pos'] = element.attributes['pos']
      batter['ab'] = element.attributes['ab']
      batter['r'] = element.attributes['r']
      batter['bb'] = element.attributes['bb']
      batter['sf'] = element.attributes['sf']
      batter['h'] = element.attributes['h']
      batter['e'] = element.attributes['e']
      batter['d'] = element.attributes['d']
      batter['t'] = element.attributes['t']
      batter['hbp'] = element.attributes['hbp']
      batter['so'] = element.attributes['so']
      batter['hr'] = element.attributes['hr']
      batter['rbi'] = element.attributes['rbi']
      batter['sb'] = element.attributes['sb']
      batter['avg'] = element.attributes['avg']
      batters.push batter
  return batters

Merge the data into the boxscore template and save the result
After you have parsed all of the relevant data out of the boxscore XML, you are ready to use that data to build the final boxscore presentation. The code below is a method in the BoxScore class that I created. This method converts the boxscore into a formatted HTML representation. The first few lines call methods which parse the boxscore XML and setup the corect data variables. After that I create a new ERb instance and load the boxscore.html.erb template into it. This is the template that I created to display the boxscore. The next line binds the template to the variables previously defined in this method and returns the result of the template bound with the variables. This produces the resultant boxscore HTML file.

  # Converts the boxscore into a formatted HTML representation.
  def to_html
    cities = get_cities
    innings = get_innings
    tots =  get_linescore_totals
    home_pitchers = get_pitchers('home')
    away_pitchers = get_pitchers('away')
    home_batters = get_batters('home')
    away_batters = get_batters('away')
    home_batters_text = get_batting_text('home')
    away_batters_text = get_batting_text('away')
    game_info = get_game_info

    gameday_info = parse_gameday_id('gid_' + gid)
    template = ERB.new File.new("boxscore.html.erb").read, nil, "%"
    return template.result(binding)

View the results and download the code
Here are links to download the complete sourcecode for my gameday API in ruby. I’ve also provided a link to a boxscore that has been generated using this code.
Full sourcecode
Generated boxscore

MLB copyright notice
If you decide to do something with my api or the MLB data, be sure that you understand the limitations of using the data. MLB provides the data for experimental usage only. You are not permitted to use it for a commercial application. Below is a line taken from their copyright notice covering all of the data available from their gameday server:
“Only individual, non-commercial, non-bulk use of the Materials is permitted and any other use of the Materials is prohibited without prior written authorization from MLBAM.”

Read the original blog entry...

More Stories By Timothy Fisher

Timothy Fisher has recognized expertise in the areas of Java, Ruby, Rails, Social Media, Web 2.0, and Enterprise 2.o. He has served in technical leadership and senior architecture roles with companies such as Motorola, Cyclone Commerce, and Compuware. He is the author of the Java Phrasebook, and the Ruby on Rails Bible. Currently he is employed as a senior web architect with Compuware in Detroit, Michigan.

Follow Timothy on Twitter at http://twitter.com/tfisher

@ThingsExpo Stories
DXWordEXPO New York 2018, colocated with CloudEXPO New York 2018 will be held November 11-13, 2018, in New York City and will bring together Cloud Computing, FinTech and Blockchain, Digital Transformation, Big Data, Internet of Things, DevOps, AI, Machine Learning and WebRTC to one location.
DXWorldEXPO LLC announced today that "Miami Blockchain Event by FinTechEXPO" has announced that its Call for Papers is now open. The two-day event will present 20 top Blockchain experts. All speaking inquiries which covers the following information can be submitted by email to [email protected] Financial enterprises in New York City, London, Singapore, and other world financial capitals are embracing a new generation of smart, automated FinTech that eliminates many cumbersome, slow, and expe...
DXWorldEXPO | CloudEXPO are the world's most influential, independent events where Cloud Computing was coined and where technology buyers and vendors meet to experience and discuss the big picture of Digital Transformation and all of the strategies, tactics, and tools they need to realize their goals. Sponsors of DXWorldEXPO | CloudEXPO benefit from unmatched branding, profile building and lead generation opportunities.
The best way to leverage your Cloud Expo presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering Cloud Expo and @ThingsExpo will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at Cloud Expo. Product announcements during our show provide your company with the most reach through our targeted audiences.
DevOpsSummit New York 2018, colocated with CloudEXPO | DXWorldEXPO New York 2018 will be held November 11-13, 2018, in New York City. Digital Transformation (DX) is a major focus with the introduction of DXWorldEXPO within the program. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive over the long term. A total of 88% of Fortune 500 companies from a generation ago are now out of bus...
With 10 simultaneous tracks, keynotes, general sessions and targeted breakout classes, @CloudEXPO and DXWorldEXPO are two of the most important technology events of the year. Since its launch over eight years ago, @CloudEXPO and DXWorldEXPO have presented a rock star faculty as well as showcased hundreds of sponsors and exhibitors! In this blog post, we provide 7 tips on how, as part of our world-class faculty, you can deliver one of the most popular sessions at our events. But before reading...
Cloud Expo | DXWorld Expo have announced the conference tracks for Cloud Expo 2018. Cloud Expo will be held June 5-7, 2018, at the Javits Center in New York City, and November 6-8, 2018, at the Santa Clara Convention Center, Santa Clara, CA. Digital Transformation (DX) is a major focus with the introduction of DX Expo within the program. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive ov...
As IoT continues to increase momentum, so does the associated risk. Secure Device Lifecycle Management (DLM) is ranked as one of the most important technology areas of IoT. Driving this trend is the realization that secure support for IoT devices provides companies the ability to deliver high-quality, reliable, secure offerings faster, create new revenue streams, and reduce support costs, all while building a competitive advantage in their markets. In this session, we will use customer use cases...
DXWorldEXPO LLC announced today that ICOHOLDER named "Media Sponsor" of Miami Blockchain Event by FinTechEXPO. ICOHOLDER give you detailed information and help the community to invest in the trusty projects. Miami Blockchain Event by FinTechEXPO has opened its Call for Papers. The two-day event will present 20 top Blockchain experts. All speaking inquiries which covers the following information can be submitted by email to [email protected] Miami Blockchain Event by FinTechEXPO also offers s...
With tough new regulations coming to Europe on data privacy in May 2018, Calligo will explain why in reality the effect is global and transforms how you consider critical data. EU GDPR fundamentally rewrites the rules for cloud, Big Data and IoT. In his session at 21st Cloud Expo, Adam Ryan, Vice President and General Manager EMEA at Calligo, examined the regulations and provided insight on how it affects technology, challenges the established rules and will usher in new levels of diligence arou...
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
Digital Transformation and Disruption, Amazon Style - What You Can Learn. Chris Kocher is a co-founder of Grey Heron, a management and strategic marketing consulting firm. He has 25+ years in both strategic and hands-on operating experience helping executives and investors build revenues and shareholder value. He has consulted with over 130 companies on innovating with new business models, product strategies and monetization. Chris has held management positions at HP and Symantec in addition to ...
Cloud-enabled transformation has evolved from cost saving measure to business innovation strategy -- one that combines the cloud with cognitive capabilities to drive market disruption. Learn how you can achieve the insight and agility you need to gain a competitive advantage. Industry-acclaimed CTO and cloud expert, Shankar Kalyana presents. Only the most exceptional IBMers are appointed with the rare distinction of IBM Fellow, the highest technical honor in the company. Shankar has also receive...
Enterprises have taken advantage of IoT to achieve important revenue and cost advantages. What is less apparent is how incumbent enterprises operating at scale have, following success with IoT, built analytic, operations management and software development capabilities - ranging from autonomous vehicles to manageable robotics installations. They have embraced these capabilities as if they were Silicon Valley startups.
Internet-of-Things discussions can end up either going down the consumer gadget rabbit hole or focused on the sort of data logging that industrial manufacturers have been doing forever. However, in fact, companies today are already using IoT data both to optimize their operational technology and to improve the experience of customer interactions in novel ways. In his session at @ThingsExpo, Gordon Haff, Red Hat Technology Evangelist, shared examples from a wide range of industries – including en...
The standardization of container runtimes and images has sparked the creation of an almost overwhelming number of new open source projects that build on and otherwise work with these specifications. Of course, there's Kubernetes, which orchestrates and manages collections of containers. It was one of the first and best-known examples of projects that make containers truly useful for production use. However, more recently, the container ecosystem has truly exploded. A service mesh like Istio addr...
Rodrigo Coutinho is part of OutSystems' founders' team and currently the Head of Product Design. He provides a cross-functional role where he supports Product Management in defining the positioning and direction of the Agile Platform, while at the same time promoting model-based development and new techniques to deliver applications in the cloud.
Predicting the future has never been more challenging - not because of the lack of data but because of the flood of ungoverned and risk laden information. Microsoft states that 2.5 exabytes of data are created every day. Expectations and reliance on data are being pushed to the limits, as demands around hybrid options continue to grow.
Business professionals no longer wonder if they'll migrate to the cloud; it's now a matter of when. The cloud environment has proved to be a major force in transitioning to an agile business model that enables quick decisions and fast implementation that solidify customer relationships. And when the cloud is combined with the power of cognitive computing, it drives innovation and transformation that achieves astounding competitive advantage.
Poor data quality and analytics drive down business value. In fact, Gartner estimated that the average financial impact of poor data quality on organizations is $9.7 million per year. But bad data is much more than a cost center. By eroding trust in information, analytics and the business decisions based on these, it is a serious impediment to digital transformation.