Prediction Markets Platform - Inkling Incorporated

Inkling REST API Documentation

Introduction

The Inkling API is vanilla XML over HTTP (secure HTTPS is also possible if your account has it enabled). In order to request that the data be returned as xml, merely append ".xml" at the end of the request URL. For any requests to a service that is sending data (e.g. the membership creation service posts xml data representing the new user) the "Content-Type" header should be set to "application/xml".

curl is a great way to explore using the API. The following is an example using curl:

curl -H 'Content-Type: application/xml' -d '<user>...</user>' http://URL/memberships.xml

Authentication is managed using HTTP authentication. Every request must include the Authorization HTTP header:

curl -u zach:changeme http://URL/trades.xml

The above will return an XML-formatted response, if it succeeds. If a request fails, the error information is returned with an HTTP status code. For example a curl request to create a user that already exists will return a 422:

  curl -H 'Content-Type: application/xml' \ 
  -u admin:password -d ' \
  <user> \
    <login>new_user</login> \ 
    <password>somepassword</password> \ 
    <email>new_user@yahoo.com</email> \
  </user> ' \
  http://subdomain.example.com/memberships.xml -v

Might output something similar to:

  > POST /memberships.xml HTTP/1.1
  > Authorization: Basic 
  > User-Agent: curl/7.16.3 (powerpc-apple-darwin9.0) libcurl/7.16.3 OpenSSL/0.9.7l zlib/1.2.3
  > Host: subdmain.example.com:80
  > Accept: */*
  > Content-Type: application/xml
  > Content-Length: 134
  > 
  < HTTP/1.1 422 
  <?xml version="1.0" encoding="UTF-8"?>
  <errors>
    <error>Login has already been taken</error>
    <error>Email has already been registered</error>
  </errors>

Also keep in mind:

Any quantity related to money (e.g. price, worth, performance, etc.) is reported in cents.
All "datetimes" of the xmlschema format (CCYY-MM-DDThh:mm:ssTZD) of a date. Where TZD is Z or [+-]hh:mm. If self is a UTC time, Z is used as TZD. [+-]hh:mm is used otherwise.
If your account has ssl enabled, make sure you use the https in your request urls.

Pagination

Any requests that return a list of objects will be paginated. To retrieve subsequent pages after the first one, simply append the "page" parameter following the request url. For example, to retrieve the second page of recent markets from your site:

  curl -u username:password http://subdomain.example.com/markets.xml?page=2

For example, a common strategy to retrieve all the markets on your site is for your client program to loop until a subsequent request no longer returns any records.