Quata - Quandl API Library and Command Line

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Quata is a lightweight ruby library for accessing Quandl, and includes a command line interface.

It provides direct access to all of the Quandl API endpoints.

Features

  • Easy to use interface.
  • Use as a library or through the command line.
  • Access any Quandl endpoint directly.
  • Display output in various formats.
  • Save output to a file, including bulk downloads.

Usage

First, require and initialize with your API key

require 'quata'
quandl = Quandl.new 'Your API Key'

Now, you can access any Quandl endpoint with any optional parameter, like this:

result = quandl.get "datasets/WIKI/AAPL", rows: 3 # => Hash

In addition, for convenience, you can use the first part of the endpoint as a method name, like this:

result = quandl.datasets "WIKI/AAPL", rows: 3

By default, you will get a ruby hash in return. If you wish to get the raw output, you can use the get! method:

result = quandl.get! "datasets/WIKI/AAPL", rows: 3 # => JSON string
result = quandl.get! "datasets/WIKI/AAPL.json", rows: 3 # => JSON string
result = quandl.get! "datasets/WIKI/AAPL.csv", rows: 3 # => CSV string

To save the output directly to a file, use the save method:

result = quandl.save "aapl.csv", "datasets/WIKI/AAPL.csv", rows: 3

Debugging your request and adding "sticky" query parameters that stay with you for the following requests is also easy:

quandl.debug true
quandl.param rows: 10, order: 'asc'
puts quandl.get 'WIKI/AAPL'
# => https://www.quandl.com/api/v3/WIKI/AAPL.json?auth_token=key&rows=10&order=asc

quandl.param order: nil # remove param

Command Line

The command line utility quata acts in a similar way. To use your Quandl API key, simply set it in the environment variables QUANDL_KEY:

$ export QUANDL_KEY=your_key

These commands are available:

$ quata get PATH [PARAMS...] - print the output.
$ quata pretty PATH [PARAMS...] - print a pretty JSON.
$ quata see PATH [PARAMS...] - print a colored output.
$ quata url PATH [PARAMS...] - show the constructed URL.
$ quata save FILE PATH [PARAMS...] - save the output to a file.

Run quata --help for more information, or view the full usage help.

Examples:

# Shows the first two databases 
$ quata see databases per_page:2

# Or more compactly, as CSV
$ quata get databases per_page:2

# Prints CSV to screen (CSV is the default in the command line)
$ quata get datasets/WIKI/AAPL

# Prints JSON instead
$ quata get datasets/WIKI/AAPL.json

# Pass arguments using the same syntax - key:value
$ quata get datasets/WIKI/AAPL rows:5

# Pass arguments that require spaces
$ quata get datasets.json "query:qqq index"

# Prints a colored output
$ quata see datasets/WIKI/AAPL rows:5

# Saves a file
$ quata save output.csv datasets/WIKI/AAPL rows:5

# Shows the URL that Quata has constructed, good for debugging
$ quata url datasets/WIKI/AAPL rows:5
# => https://www.quandl.com/api/v3/datasets/WIKI/AAPL.csv?auth_token=YOUR_KEY&rows=5

Quata Demo