Create a chart in Ruby on Rails

FusionTime is a JavaScript charting library that helps you visualize, and explore time-series data. In FusionTime, you get lots of out-of-the-box interactivity, like, time navigator, date range selectors, tooltips with crosslines, interactive legend and more features which enhances the experience of exploring and understanding time series data.

We have built a simple FusionCharts server-side ruby-on-rails wrapper, which provides bindings for FusionTime. The FusionCharts server-side ruby-on-rails wrapper allows you to easily add interactive time-series charts to any Ruby on Rails project.

Installation

In this article, we will show you how to download and install the FusionCharts Rails gem wrapper and all the other dependencies on your system. Since FusionTime is distributed along with FusionCharts Suite, download/install the FusionCharts package to get access to FusionTime.

• Copy the fusionCharts-rails.rb from integrations > rubyonrails > fusioncharts-wrapper in your project folder.

• Include the FusionCharts JavaScript files, which can be downloaded from here.

• Include the FusionTime file to render time-series charts.

// Include FusionCharts core file
<script type="text/javascript" src="https://cdn.fusioncharts.com/fusioncharts/latest/fusioncharts.js"></script>

// Include FusionCharts Theme file
<script type="text/javascript" src="https://cdn.fusioncharts.com/fusioncharts/latest/themes/fusioncharts.theme.fusion.js"></script>
COPY

// Include FusionCharts core file
<script type="text/javascript" src="path/to/local/fusioncharts.js"></script>

// Include FusionCharts Theme file
<script type="text/javascript" src="path/to/local/themes/fusioncharts.theme.fusion.js"></script>
COPY

• Add the FusionCharts Rail wrapper:
  • Using RubyGems
  • Manually
• Include the FusionCharts Rails wrapper.

To add the FusionCharts Rails wrapper, use any of the following processes:

    gem ‘fusioncharts-rails’
COPY

    $bundle
COPY

    $gem install fusioncharts-rails
COPY

Create Your First Chart

Now that you have installed FusionTime and FusionCharts server-side Ruby on Rails wrapper, let us build the first chart to show the "Daily sales of a grocery store".

The chart will look as shown below:

The data for the above chart is shown in the table below:

FusionCharts accepts a DataTable as the data source. DataTable is a part of DataStore, which is a tabular representation of the data. To create the DataTable, you need to provide the following:

• schema - which defines the properties of the columns.

• data - values of each row and column of the DataTable.

For an instance of FusionTime, you can create n number of DataTables, but only one DataStore.

Next, let's learn how to prepare the schema and the data of the DataTable.

Create the schema

The schema outlines each column represented in the above table. The schema contains an array which has multiple objects created in it. Each object represents a column in the DataTable.

name and type are mandatory keys for each object. If the object type is time then format is also a mandatory key.

To define the schema, let's create a schema.json file and copy the following code:

It is not mandatory to create the schema in a different .json file. You can also define the schema within the .html file.

[
  {
    "name": "Time",
    "type": "date",
    "format": "%-m/%-d/%Y"
  },
  {
    "name": "Sales",
    "type": "number"
  }
]COPY

In the above code:

• Each object of the schema maps to a column of the tabular representation of the data.

• The JSON object has the following attributes:

  • name - Specify the name of the column of the tabular representation of data

  • type - Specify the type of the column.

  • format - Specify the input format of the date as per your data. In this example, the format is %-m/%-d/%Y. To know more about date formats, click here.

Now that we have the schema ready, let's work on the data.

Create the data

Data for the above chart is too big to be shown here. A sample of it has been used in the data object defined below:

[
  ["1/4/2011", 16.448],
  ["1/5/2011", 272.736],
  ["1/5/2011", 11.784],
  ["1/5/2011", 3.54],
  ["1/6/2011", 19.536],
  ["1/7/2011", 2573.82]
]COPY

Create a new data.json file, and copy the above code there. Next, copy the entire and replace it with the content of the data object in your 'data.json' file.

** **It is not mandatory to create a data.json file. You could also do the same in your HTML file.

In the above code:

• Each object in the data array corresponds to a row in the tabular representation of the data.

• Each element in an object is represented by each object of the schema. The values in each object of the array represent the following:

  • Time according to the format

  • Total Sales amount

We are all set with our data to create the chart.

By default, FusionTime applies the average function to aggregate the data and display on the chart. You can change the aggregate function from average to any other numeric calculation. To know more, click here.

Now, let's create the files to render the above chart.

Render the chart

Once you have the data and the schema ready, follow the steps below:

1. Include the FusionCharts Rails wrapper in your project.

2. Include the fusioncharts library.

3. Declare the the local variables to consume the informations from data and schema.

4. Fetch the informations from data and schema from remote URL and store it to your local data and schema variables.

5. Create and initialize the FusionTable object instance with the constructor parameter of data and schema.

6. Create and initialize the TimeSeries object instance with the constructor parameter of FusionTable object instance.

7. The following parameter values have been set for the wrapper constructor:

   • Value of width has been set to 700.

   • Value of height has been set to 450.

   • Value of type has been set to timeseries.

   • Value of renderAt has been set to chartContainer.

   • Value of dataFormat has been set to json

   • The time-series object timeSeries has been provided.

8. Create a container using <div> to render the chart.

The full code for the above sample is:

<!-- Filename: app/views/examples/firstchart.rb -->

require 'json'
require 'open-uri'
require 'fusioncharts-rails'

class FirstChart
def self.getChart

# Declare local variables for consuming schema and data information.
#Fetch data and schema information from remote url and store these in local schema and data variables.

data = open('..PATH/data.json') {
    | f | f.read
}
schema = open('..PATH/schema.json') {
    | f | f.read
}

# Create and initialize FusionTable object instance with the constructor parameters of data and schema.
fusionTable = Fusioncharts::FusionTable.new(schema, data)

# Create and initialize TimeSeries object instance with the constructor parameters of FusionTable object instance.
timeSeries = Fusioncharts::TimeSeries.new(fusionTable)

# Wrapper constructor parameters# width: Width of the chart, #height: Height of the chart, #type: ChartType, #renderAt: Id of the container where the chart will be rendered, #dataFormat: format of the data, this wrapper for timeseries chart type supports only json format, #timeSeries: Accepts only TimeSeries class object instance

# Chart rendering
chart = Fusioncharts::Chart.new({
    width: "700",
    height: "400",
    type: "timeseries",
    renderAt: "chartContainer",
    dataFormat: 'json',
    timeSeries: timeSeries
})

end
endCOPY

The HTML template of the above sample is shown below:

<!-- Filename: app/views/layouts/firstchart.html.erb -->
<h3>My Chart</h3>
<div id="chartContainer"></div>
<%=@first_chart.render() %>COPY

That's it! Your first chart in Ruby on Rails using FusionTime is ready.