Google Chart Images Replacement [closed]

Answer 1

My team at Ramen recently built exactly this. It's called ChartURL. It's not forever-free like Google Charts API is, but there is a pretty generous free tier.

It lets you construct URLs in two ways. First, you can encrypt the data into the URL. We use encryption for accounting purposes (since it's not forever-free). In both cases, you encode a template_slug and your data into the URL. The template_slug is a string representation of a chart configuration you can modify, preview, and save inside your account on ChartURL.com. So you can have email-bar-chart-1 and email-bar-chart-2 and timeseries-signups each with their own style/config, and then just send in the data you want graphed inside that template.

Here's an example of generating a URL in ruby:

# This is a working example. View fully commented version here:
# https://gist.github.com/ryana/055414a4804806263b82
require 'json'
require 'openssl'
require 'base64'
require 'cgi'

ENCRYPT_KEY = "dek-d7a46236eda961a6c3c18ffcc6b077ba87d27e9ae85f7842c6d427c265dd5f69d5131308d93332353d4a55a4b1160fcf516515a4a9f0aa50fbf2d7a2e7d0f1c5"
ENCRYPT_KEY_DIGEST = KEY_DIGEST = OpenSSL::Digest::SHA256.new(ENCRYPT_KEY).digest
PROJECT_TOKEN = "dt-RwYN"

def charturl_url(template_slug, data)
  json = {options: data}.to_json
  cipher = OpenSSL::Cipher.new 'AES-256-CBC'
  cipher.encrypt
  iv = cipher.random_iv
  cipher.key = ENCRYPT_KEY_DIGEST
  encrypted_json = cipher.update(json) + cipher.final

  iv_for_url = CGI.escape(Base64.encode64(iv))
  data_for_url = CGI.escape(Base64.encode64(encrypted_json))

  "https://charturl.com/i/#{PROJECT_TOKEN}/#{template_slug}/#{iv_for_url}/#{data_for_url}"  
end

# Call our helper
url = charturl_url("weekly-activity",
    data: {columns: [["This Week", 10,12,41,9,14,15,15], ["Last Week", 9,14,21,21,20,3,5]]})

#=> https://charturl.com/i/dt-RwYN/weekly-activity/nEPfObOZ3zTivXZqri8ZLA%3D%3D%0A/7X6WrBHEdRcnutV0fU0sN8s9mHFGkkRr%2FZYJwb43p8PDzAJvGWd37zi6ro70%0AVJd9f%2FkSIq2dmJzGe%2BW6CSlpUIrhXHXogvXd%2B%2Fk4VOS%2BTSlnMBwKOSJJNpGZ%0AVrLZd%2Fgq1mSbiXQnc%2FydiTVcGL2DaA%3D%3D%0A

Because URLs have a character limit, we also provide an API that allows you to POST us data and we'll return a short URL:

# This is a working example. View fully commented version here:
# https://gist.github.com/ryana/d37fccd7af3c6c409164/
require 'json'
require 'typhoeus'

API_KEY = "dak-55045dac-bb35-40ac-80c8-874ab71c6f83"

def charturl_url(template_slug, options)
  url = "https://charturl.com/short-urls.json?api_key=#{API_KEY}"
  headers = {'Content-Type' => 'application/json'}
  body = {template: template_slug, options: options}.to_json
  surl_response = Typhoeus::Request.post(url, body: body, headers: headers)
  raise("Error creating ShortURL: #{surl_response.inspect}") if !surl_response.success?
  JSON.parse(surl_response.body)['short_url']
end

# Call our helper
url = charturl_url("weekly-activity", data: {columns: [["This week", 4,1,5,6,1,7,8], ["Last week", 1,5,3,1,6,2,6]]})
url #=> "https://charturl.com/r/J9lA"