PolarDB:Signature method

1. Create a canonicalized query string by arranging the request parameters in alphabetical order. Include all common and operation-specific parameters except Signature.

   If you use the GET method to submit the request, these parameters are the part of the request URI located after the question mark (?) and connected by ampersands (&).

2. Encode the canonicalized query string in UTF-8. The following list describes the rules of percent encoding:

   • Letters, digits, hyphens (-), underscores (_), periods (.), and tildes (~) do not need to be encoded.

   • Other characters must be encoded in %XY format, where XY represents the ASCII code of the characters in hexadecimal notation. For example, double quotation marks (") are encoded as %22.

   • Extended UTF-8 characters are encoded in %XY%ZA... format.

   • Spaces must be encoded as %20. Do not encode spaces as plus signs (+).

     This encoding method is different from the application/x-www-form-urlencoded MIME encoding method, which is used by the java.net.URLEncoder class in the Java standard library. To convert such texts to percent encoded format, replace plus signs (+) in the encoded string with %20, asterisks (*) with %2A, and %7E with tildes (~). The following percentEncode method performs this conversion:

     private static final String ENCODING = "UTF-8";
     private static String percentEncode(String value) throws UnsupportedEncodingException 
     {
     return value ! = null ? URLEncoder.encode(value, ENCODING).replace("+", "%20").replace("*", "%2A").replace("%7E", "~") : null;
     }

   • Connect each encoded parameter name with its encoded value by using an equal sign (=).
   • Sort the parameter name and value pairs in the order specified in Step i. Then connect the pairs with ampersands (&) to produce the canonicalized query string.

StringToSign=
      HTTPMethod + "&" +
      percentEncode("/") + "&" +
       percentEncode(CanonicalizedQueryString)

where:

• HTTPMethod is the HTTP method used to make the request, such as GET.
• percentEncode("/") encodes the backslashes (/) in the URL as %2F.
• percentEncode(CanonicalizedQueryString) encodes the canonicalized query string based on the URL encoding rules described in Step 1.2.