Using the sunsky api with ruby

The api is pretty simple to understand looking at the example PHP code. Each request needs to send the signed parameters. The signature is a simple md5 with the secret at the end. The important thing is that the keys are sorted alphabeticaly!

def sign(parameters,secret)
  signature=''
  parameters.sort.each {|key,value|signature+=value}
  signature+="@#{secret}"
  Digest::MD5.hexdigest(signature)
end

then there is the call and download function which are basicaly the same, only difference is that the download function saves a zip file.

def call(api_url,secret,parameters)
  signature=sign(parameters,secret)
  parameters['signature'] = signature
  uri = URI.parse(api_url)
  response = Net::HTTP.post_form(uri, parameters)
  response.body
end

for the download, we can reuse the call method and just dump the data to a file

def download(api_url, secret, parameters, path)
  data=call(api_url,secret,parameters)
  File.open(path, 'w') { |file| file.write(data) }
end

putting it all together

require 'digest'
require 'net/http'

def sign(parameters,secret)
  signature=''
  parameters.sort.each {|key,value|signature+=value}
  signature+="@#{secret}"
  Digest::MD5.hexdigest(signature)
end

def call(api_url,secret,parameters)
  signature=sign(parameters,secret)
  parameters['signature'] = signature
  uri = URI.parse(api_url)
  response = Net::HTTP.post_form(uri, parameters)
  response.body
end

def download(api_url, secret, parameters, path)
  data=call(api_url,secret,parameters)
  File.open(path, 'w') { |file| file.write(data) }
end

key = "MYKEY";
secret = "VERYSECRET";

api_url="http://www.sunsky-api.com/openapi/product!getImages.do"
parameters={
  'key'    =>key,
  'itemNo' => 'S-SCS-2850W'
}

download(api_url, secret, parameters, "foo.zip")