Amazon API Signature Algorithm (version Golang and Java edition)

This is a creation in Article, where the information may have evolved or changed.

Package Mainimport "FMT" import "Crypto/hmac" import "crypto/sha256" import "Time" import "strings" Import encoding/ Base64 "Import" net/http "import" Net/url "import" io/ioutil "Const METHOD =" GET "Const HOST =" Webservices.amazon.com " Const uri= "/onca/xml" Const query_string= "awsaccesskeyid=121212121212&associatetag=smasholab-20&idtype= isbn&itemid=b000mqtjw2&operation=itemlookup&service=awsecommerceservice&timestamp=%s "Func Main ( ) {T: = time. Now () tm:= T.format ("2006-01-02t15:04:05z") tm= URL. Queryescape (tm) FMT. PRINTLN ("TM:", tm) Query: = FMT. Sprintf (Query_string, TM) UL: = FMT. Sprintf (Query_string, TM) FMT. PRINTLN ("Query:", "Query")//awsaccesskeyid: = "SSSBBBSSSBBB" Awssecretkeyid: = "Ooxxooxx" sha256: = sha256. Newhash: = HMAC. New (SHA256, []byte (Awssecretkeyid)) template:= "%s\n%s\n%s\n%s" template= fmt. Sprintf (template, METHOD, HOST, URI, query) fmt. Println ("Template:", template) hash. Write ([]byte (Template)) Sha: = base64. Stdencoding.encodetostring (hash. Sum (nil)) sha= URL. Queryescape(SHA) fmt. Println ("Sha", Sha) ul= ul + "&signature=" +shaul= "Http://webservices.amazon.com/onca/xml?" + UL ul= strings. Replace (UL, "+", "%20",-1) ul= strings. Replace (UL, "*", "%2a",-1) ul= strings. Replace (UL, "%7e", "~",-1) fmt. Println ("URL:", ul)//requestresponse, err: = http. Get (UL) if err! = Nil {fmt. Println ("Err", err)}else{content, _: = Ioutil. ReadAll (response. Body) println ("Response", string (content)) response. Body.close ()}}

------------------------The following is the Java version, a little verbose point----------------------------------

Package Com.amazon.associates.sample;import Java.io.unsupportedencodingexception;import Java.net.URLDecoder; Import Java.net.urlencoder;import Java.security.invalidkeyexception;import java.security.NoSuchAlgorithmException ; Import Java.text.dateformat;import java.text.simpledateformat;import java.util.calendar;import java.util.HashMap; Import Java.util.iterator;import java.util.map;import Java.util.sortedmap;import Java.util.timezone;import Java.util.treemap;import Javax.crypto.mac;import Javax.crypto.spec.secretkeyspec;import Org.apache.commons.codec.binary.base64;public class Signedrequestshelper {private static final String Utf8_charset = "U  TF-8 ";  private static final String Hmac_sha256_algorithm = "HmacSHA256";  private static final String Request_uri = "/onca/xml";  private static final String Request_method = "GET"; Private String endpoint = "webservices.amazon.com";  Must be lowercase private String Awsaccesskeyid = "YOUR AWS ACCESS KEY"; Private String Awssecretkey = "YOUR AWS SECRET KEY ";  Private Secretkeyspec secretkeyspec = null;  Private Mac Mac = null;    Public Signedrequestshelper () {byte[] secretykeybytes = awssecretkey.getbytes (Utf8_charset);    Secretkeyspec = new Secretkeyspec (secretykeybytes, hmac_sha256_algorithm);    Mac = Mac.getinstance (hmac_sha256_algorithm);  Mac.init (SECRETKEYSPEC);    Public String sign (map<string, string> params) {params.put ("Awsaccesskeyid", Awsaccesskeyid);    Params.put ("Timestamp", Timestamp ());    sortedmap<string, string> sortedparammap = new treemap<string, string> (params);    String Canonicalqs = canonicalize (Sortedparammap);    String tosign = request_method + "\ n" + endpoint + "\ n" + Request_uri + "\ n" + Canonicalqs;    String HMAC = HMAC (tosign);    String sig = percentEncodeRfc3986 (HMAC);    String url = "http://" + endpoint + Request_uri + "?" + Canonicalqs + "&signature=" + sig;  return URL; } private String HMAC (String stringtosign){String signature = null;    byte[] data;    Byte[] Rawhmac;      try {data = Stringtosign.getbytes (Utf8_charset);      Rawhmac = mac.dofinal (data);      BASE64 encoder = new Base64 ();    Signature = new String (Encoder.encode (RAWHMAC));    } catch (Unsupportedencodingexception e) {throw new RuntimeException (Utf8_charset + "is unsupported!", e);  } return signature;    private string Timestamp () {string timestamp = null;    Calendar cal = Calendar.getinstance ();    DateFormat DFM = new SimpleDateFormat ("Yyyy-mm-dd ' T ' HH:mm:ss ' Z ');    Dfm.settimezone (Timezone.gettimezone ("GMT"));    timestamp = Dfm.format (Cal.gettime ());  return timestamp; } private String canonicalize (sortedmap<string, string> sortedparammap) {if (Sortedparammap.isempty ()) {RE    Turn "";    } stringbuffer buffer = new StringBuffer ();    Iterator<map.entry<string, string>> iter = Sortedparammap.entryset (). Iterator (); while (Iter.hasnext ()) {Map.entry<string, string> Kvpair = Iter.next ();      Buffer.append (percentEncodeRfc3986 (Kvpair.getkey ()));      Buffer.append ("=");      Buffer.append (percentEncodeRfc3986 (Kvpair.getvalue ()));      if (Iter.hasnext ()) {Buffer.append ("&");    }} String canonical = Buffer.tostring ();  return canonical;    } private String percentEncodeRfc3986 (string s) {string out; try {out = Urlencoder.encode (S, utf8_charset). Replace ("+", "%20"). Replace ("*", "%2a"). Replace ("%7e    ", "~");    } catch (Unsupportedencodingexception e) {out = s;  } return out; }}