Refactor project structure

library/src/main/java/com/echsylon/kraken/Kraken.java

@@ -1,13 +1,32 @@
 package com.echsylon.kraken;
 
 import com.echsylon.blocks.network.OkHttpNetworkClient;
-import com.echsylon.kraken.dto.Depth;
-import com.echsylon.kraken.dto.OrderAddReceipt;
-import com.echsylon.kraken.dto.Trade;
+import com.echsylon.kraken.internal.CallCounter;
+import com.echsylon.kraken.request.AccountBalanceRequestBuilder;
+import com.echsylon.kraken.request.AddOrderRequestBuilder;
+import com.echsylon.kraken.request.AssetInfoRequestBuilder;
+import com.echsylon.kraken.request.CancelOrderRequestBuilder;
+import com.echsylon.kraken.request.ClosedOrdersRequestBuilder;
+import com.echsylon.kraken.request.LedgersRequestBuilder;
+import com.echsylon.kraken.request.OhlcDataRequestBuilder;
+import com.echsylon.kraken.request.OpenOrdersRequestBuilder;
+import com.echsylon.kraken.request.OpenPositionsRequestBuilder;
+import com.echsylon.kraken.request.OrderBookRequestBuilder;
+import com.echsylon.kraken.request.QueryLedgersRequestBuilder;
+import com.echsylon.kraken.request.QueryOrdersRequestBuilder;
+import com.echsylon.kraken.request.QueryTradesRequestBuilder;
+import com.echsylon.kraken.request.RecentSpreadRequestBuilder;
+import com.echsylon.kraken.request.RecentTradesRequestBuilder;
+import com.echsylon.kraken.request.ServerTimeRequestBuilder;
+import com.echsylon.kraken.request.TickerInfoRequestBuilder;
+import com.echsylon.kraken.request.TradableAssetPairsRequestBuilder;
+import com.echsylon.kraken.request.TradeBalanceRequestBuilder;
+import com.echsylon.kraken.request.TradeHistoryRequestBuilder;
+import com.echsylon.kraken.request.TradeVolumeRequestBuilder;
 
 import java.io.File;
 
-import static com.echsylon.kraken.Utils.base64Decode;
+import static com.echsylon.kraken.internal.Utils.base64Decode;
 
 /**
  * This class describes the Kraken API.
@@ -64,10 +83,6 @@ public static void clearCallRateLimit() {
      *
      * @param baseUrl The base url to the test environment.
      */
-    Kraken(String baseUrl) {
-        this(baseUrl, null, null);
-    }
-
     Kraken(String baseUrl, String key, String secret) {
         this.baseUrl = baseUrl;
         this.key = key;
@@ -165,7 +180,7 @@ public OhlcDataRequestBuilder getOhlcData(final String pair) {
      * @return A request builder object to configure the request and any client
      * side cache metrics with, and to attach any callback implementations to.
      */
-    public RequestBuilder<Dictionary<Depth>> getOrderBook(final String pair) {
+    public OrderBookRequestBuilder getOrderBook(final String pair) {
         return new OrderBookRequestBuilder(callCounter, baseUrl, key, secret)
                 .useAssetPair(pair);
     }
@@ -178,7 +193,7 @@ public RequestBuilder<Dictionary<Depth>> getOrderBook(final String pair) {
      * @return A request builder object to configure the request and any client
      * side cache metrics with, and to attach any callback implementations to.
      */
-    public RequestBuilder<Dictionary<Trade[]>> getRecentTrades(final String pair) {
+    public RecentTradesRequestBuilder getRecentTrades(final String pair) {
         return new RecentTradesRequestBuilder(callCounter, baseUrl, key, secret)
                 .useAssetPair(pair);
     }
@@ -327,10 +342,10 @@ public TradeVolumeRequestBuilder getTradeVolume() {
      * @return A request builder object to configure the request and any client
      * side cache metrics with, and to attach any callback implementations to.
      */
-    public RequestBuilder<OrderAddReceipt> addStandardOrder(final String pair,
-                                                            final String type,
-                                                            final String orderType,
-                                                            final String price) {
+    public AddOrderRequestBuilder addStandardOrder(final String pair,
+                                                   final String type,
+                                                   final String orderType,
+                                                   final String price) {
         return new AddOrderRequestBuilder(callCounter, baseUrl, key, secret)
                 .useAssetPair(pair)
                 .useType(type)

library/src/main/java/com/echsylon/kraken/CallCounter.java → library/src/main/java/com/echsylon/kraken/internal/CallCounter.java

@@ -1,10 +1,10 @@
-package com.echsylon.kraken;
+package com.echsylon.kraken.internal;
 
 /**
  * This class know how to calculate the call rate limit state for API requests
  * and will temporary block the thread if the limit is exceeded.
  */
-final class CallCounter {
+public final class CallCounter {
     private final int decreaseInterval;
     private final int maxCount;
 
@@ -18,7 +18,7 @@ final class CallCounter {
      *
      * @param tier The tier that decides which call rate limit rules to apply.
      */
-    CallCounter(int tier) {
+    public CallCounter(int tier) {
         lastCallTime = 0L;
         callCounter = 0;
 
@@ -50,7 +50,7 @@ final class CallCounter {
      *
      * @param cost The cost of the request being handled right now.
      */
-    synchronized void allocate(int cost) {
+    public synchronized void allocate(int cost) {
         // Early bail-out
         if (lastCallTime == 0L) {
             callCounter += cost;

library/src/main/java/com/echsylon/kraken/KrakenTypeAdapterFactory.java → library/src/main/java/com/echsylon/kraken/internal/KrakenTypeAdapterFactory.java

@@ -1,5 +1,6 @@
-package com.echsylon.kraken;
+package com.echsylon.kraken.internal;
 
+import com.echsylon.kraken.Dictionary;
 import com.echsylon.kraken.dto.AssetPair;
 import com.echsylon.kraken.dto.Depth;
 import com.echsylon.kraken.dto.Ohlc;
@@ -22,7 +23,7 @@
  * are used for those cases where the Kraken API returns an array of data as a
  * tuple that's more suitable to represent as a POJO.
  */
-final class KrakenTypeAdapterFactory implements TypeAdapterFactory {
+public final class KrakenTypeAdapterFactory implements TypeAdapterFactory {
 
     @Override
     @SuppressWarnings("unchecked")

library/src/main/java/com/echsylon/kraken/Utils.java → library/src/main/java/com/echsylon/kraken/internal/Utils.java

@@ -1,22 +1,28 @@
-package com.echsylon.kraken;
+package com.echsylon.kraken.internal;
 
+import android.net.Uri;
 import android.util.Base64;
 
 import com.annimon.stream.Stream;
+import com.echsylon.blocks.network.NetworkClient;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.security.InvalidKeyException;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 import javax.crypto.Mac;
 import javax.crypto.spec.SecretKeySpec;
 
 /**
  * This class provides internal helper functions.
  */
-final class Utils {
+public final class Utils {
 
     /**
      * Joins any provided non-empty string fragments into a comma separated
@@ -25,7 +31,7 @@ final class Utils {
      * @param fragments The string fragments to join.
      * @return A comma separated string or null if no fragments provided.
      */
-    static String join(String... fragments) {
+    public static String join(String... fragments) {
         if (fragments == null || fragments.length <= 0)
             return null;
 
@@ -50,7 +56,7 @@ static String join(String... fragments) {
      * @param value The byte array to express as a string.
      * @return The value as a string or null if the input is null.
      */
-    static String asString(byte[] value) {
+    public static String asString(byte[] value) {
         return value != null ?
                 new String(value) :
                 null;
@@ -62,7 +68,7 @@ static String asString(byte[] value) {
      * @param value The object who's value to express as a string.
      * @return The value as a string or null if the input is null.
      */
-    static String asString(Long value) {
+    public static String asString(Long value) {
         return value != null ?
                 value.toString() :
                 null;
@@ -74,7 +80,7 @@ static String asString(Long value) {
      * @param value The object who's value to express as a string.
      * @return The value as a string or null if the input is null.
      */
-    static String asString(Integer value) {
+    public static String asString(Integer value) {
         return value != null ?
                 value.toString() :
                 null;
@@ -86,7 +92,7 @@ static String asString(Integer value) {
      * @param value The object who's value to express as a string.
      * @return The "true" or "false" or null if the input is null.
      */
-    static String asString(Boolean value) {
+    public static String asString(Boolean value) {
         return value != null ?
                 value.toString() :
                 null;
@@ -99,7 +105,7 @@ static String asString(Boolean value) {
      * @param string The string to convert to a byte array.
      * @return The string byte array or null if the input is null.
      */
-    static byte[] asBytes(String string) {
+    public static byte[] asBytes(String string) {
         if (string == null)
             return null;
 
@@ -114,7 +120,7 @@ static byte[] asBytes(String string) {
      * @return The resulting byte array (may be empty) or null if the input is
      * null.
      */
-    static byte[] concat(byte[]... bytes) {
+    public static byte[] concat(byte[]... bytes) {
         return bytes != null ?
                 Stream.of(bytes)
                         .reduce(new ByteArrayOutputStream(), (stream, array) -> {
@@ -136,7 +142,7 @@ static byte[] concat(byte[]... bytes) {
      * @param secret  The encryption secret.
      * @return the encrypted byte array.
      */
-    static byte[] hmacSha512(byte[] message, byte[] secret) {
+    public static byte[] hmacSha512(byte[] message, byte[] secret) {
         try {
             Mac mac = Mac.getInstance("HmacSHA512");
             mac.init(new SecretKeySpec(secret, "HmacSHA512"));
@@ -152,7 +158,7 @@ static byte[] hmacSha512(byte[] message, byte[] secret) {
      * @param message The data to encrypt.
      * @return the encrypted byte array.
      */
-    static byte[] sha256(byte[] message) {
+    public static byte[] sha256(byte[] message) {
         if (message == null)
             return null;
 
@@ -170,7 +176,7 @@ static byte[] sha256(byte[] message) {
      * @param string The string to decode.
      * @return The decoded string as a byte array.
      */
-    static byte[] base64Decode(String string) {
+    public static byte[] base64Decode(String string) {
         return string != null ?
                 Base64.decode(string, Base64.DEFAULT) :
                 null;
@@ -182,10 +188,106 @@ static byte[] base64Decode(String string) {
      * @param bytes The bytes to encode.
      * @return The encoded byte array as a string.
      */
-    static String base64Encode(byte[] bytes) {
+    public static String base64Encode(byte[] bytes) {
         return bytes != null ?
                 Base64.encodeToString(bytes, Base64.NO_WRAP) :
                 null;
     }
 
+    /**
+     * Checks whether a given url is targeting a private endpoint in the Kraken
+     * API.
+     *
+     * @param url The url to check.
+     * @return Boolean true if targeting a private endpoint, false otherwise.
+     */
+    public static boolean isPrivateRequest(final String url) {
+        return url.contains("/private/");
+    }
+
+    /**
+     * Generates a nonce for private requests, or null for public requests.
+     *
+     * @return The nonce or null.
+     */
+    public static String generateNonce(final String url) {
+        return url != null && isPrivateRequest(url) ?
+                String.format("%-16s", System.currentTimeMillis())
+                        .replace(" ", "0") :
+                null;
+    }
+
+    /**
+     * Constructs an encoded request message that Kraken will understand. See
+     * Kraken API documentation for details.
+     *
+     * @param nonce The request nonce. Ignored if null.
+     * @param data  The actual key value pairs to build the message from. Even
+     *              positions are treated as keys and odd positions as values.
+     *              Any null pointer key or value will render the key/value pair
+     *              invalid and hence ignored. Any trailing single keys will
+     *              also be ignored.
+     * @return The prepared and encoded Kraken message.
+     */
+    public static String composeMessage(final String nonce,
+                                        final HashMap<String, String> data) {
+
+        Uri.Builder builder = new Uri.Builder();
+
+        if (nonce != null)
+            builder.appendQueryParameter("nonce", nonce);
+
+        if (data != null && !data.isEmpty())
+            for (Map.Entry<String, String> entry : data.entrySet()) {
+                String key = entry.getKey();
+                String value = entry.getValue();
+                if (key != null && value != null)
+                    builder.appendQueryParameter(key, value);
+            }
+
+        return builder.build().getEncodedQuery();
+    }
+
+    /**
+     * Generates the message signature headers. See Kraken API documentation for
+     * details.
+     *
+     * @param key     The API key.
+     * @param secret  The corresponding (decoded) key secret.
+     * @param path    The request path.
+     * @param nonce   The request nonce that was used for the message.
+     * @param message The request message
+     * @return The Kraken request signature headers. Null if no path is given or
+     * an empty list if no nonce is given.
+     */
+    public static List<NetworkClient.Header> generateSignatureHeaders(final String key,
+                                                                      final byte[] secret,
+                                                                      final String path,
+                                                                      final String nonce,
+                                                                      final String message) {
+        if (key == null || secret == null)
+            return null;
+
+        if (path == null)
+            return null;
+
+        if (nonce == null)
+            return null;
+
+        byte[] data = sha256(asBytes(nonce + message));
+        if (data == null)
+            return null;
+
+        byte[] input = concat(asBytes(path), data);
+        byte[] signature = hmacSha512(input, secret);
+        if (signature == null)
+            return null;
+
+        List<NetworkClient.Header> headers = new ArrayList<>(2);
+        headers.add(new NetworkClient.Header("API-Key", key));
+        headers.add(new NetworkClient.Header("API-Sign", base64Encode(signature)));
+
+        return headers;
+    }
+
 }

library/src/main/java/com/echsylon/kraken/AccountBalanceRequestBuilder.java → library/src/main/java/com/echsylon/kraken/request/AccountBalanceRequestBuilder.java

@@ -1,5 +1,7 @@
-package com.echsylon.kraken;
+package com.echsylon.kraken.request;
 
+import com.echsylon.kraken.Dictionary;
+import com.echsylon.kraken.internal.CallCounter;
 import com.google.gson.reflect.TypeToken;
 
 /**
@@ -20,10 +22,10 @@ public class AccountBalanceRequestBuilder extends RequestBuilder<Dictionary<Stri
      * @param key         The user API key.
      * @param secret      The corresponding secret.
      */
-    AccountBalanceRequestBuilder(final CallCounter callCounter,
-                                 final String baseUrl,
-                                 final String key,
-                                 final byte[] secret) {
+    public AccountBalanceRequestBuilder(final CallCounter callCounter,
+                                        final String baseUrl,
+                                        final String key,
+                                        final byte[] secret) {
 
         super(1, callCounter, key, secret, baseUrl,
                 "POST", "/0/private/Balance",