Parameters Encoding
Take into account that the values of the parameters that are part of the path or the query string of the URIs of the different API operations must be encoded as specified in RFC 2396. In particular, remember that you must encode the characters '+', '=' and '/' that appear in base64 parameter values with the sequences '%2B', '%2F', and '%3D' (e.g. the value of the digests_summary parameter of the Obtain Authorization operation).
Also, note that the values of the parameters that are included in application/x-www-form-urlencoded type contents that are put in the request bodies of some API operations (e.g. Obtain a Token) must be encoded as indicated in the application/x-www-form-urlencoded section of the HTML specification.