Proxy api improvements & fixes

Http get empty response handle
Http post implementation
New models introduced

Author: GoodforGod

src/main/java/io/api/etherscan/App.java

@@ -1,10 +1,7 @@
 package io.api.etherscan;
 
 import io.api.etherscan.core.impl.EtherScanApi;
-import io.api.etherscan.model.Tx;
-import io.api.etherscan.model.TxInternal;
-import io.api.etherscan.model.TxToken;
-import io.api.etherscan.model.UncleBlock;
+import io.api.etherscan.model.*;
 
 import java.util.List;
 import java.util.Optional;
@@ -15,6 +12,7 @@
 public class App {
     public static void main(String[] args) {
         EtherScanApi api = new EtherScanApi(args[0]);
+        Balance balance = api.account().balance("0x8d4426f94e42f721C7116E81d6688cd935cB3b4F");
         List<Tx> txs = api.account().txs("0x8d4426f94e42f721C7116E81d6688cd935cB3b4F");
         List<TxToken> txTokens = api.account().txsToken("0xf261B3A60Ef40eE0B369B0705c1a2c58B02799DF");
         List<TxInternal> txInternals = api.account().txsInternal("0x2c1ba59d6f58433fb1eaee7d20b26ed83bda51a3");

src/main/java/io/api/etherscan/core/IProxyApi.java

@@ -2,6 +2,7 @@
 
 import io.api.etherscan.error.ApiException;
 import io.api.etherscan.model.proxy.BlockProxy;
+import io.api.etherscan.model.proxy.TxInfoProxy;
 import io.api.etherscan.model.proxy.TxProxy;
 import org.jetbrains.annotations.NotNull;
 
@@ -17,49 +18,89 @@
  */
 public interface IProxyApi {
 
-    /** Returns the number of most recent block */
+    /**
+     * Returns the number of most recent block
+     * eth_blockNumber
+     */
     long blockNoLast();
 
-    /** Returns information about a block by block number */
+    /**
+     * Returns information about a block by block number
+     * eth_getBlockByNumber
+     */
     @NotNull Optional<BlockProxy> block(long blockNo) throws ApiException;
 
-    /** Returns information about a uncle by block number */
+    /**
+     * Returns information about a uncle by block number
+     * eth_getUncleByBlockNumberAndIndex
+     */
     @NotNull Optional<BlockProxy> blockUncle(long blockNo, long index) throws ApiException;
 
-    /** Returns the information about a transaction requested by transaction hash */
+    /**
+     * Returns the information about a transaction requested by transaction hash
+     * eth_getTransactionByHash
+     */
     @NotNull Optional<TxProxy> tx(String txhash) throws ApiException;
 
-    /** Returns information about a transaction by block number and transaction index position */
+    /**
+     * Returns information about a transaction by block number and transaction index position
+     * eth_getTransactionByBlockNumberAndIndex
+     */
     @NotNull Optional<TxProxy> tx(long blockNo, long index) throws ApiException;
 
-    /** Returns the number of transactions in a block from a block matching the given block number */
+    /**
+     * Returns the number of transactions in a block from a block matching the given block number
+     * eth_getBlockTransactionCountByNumber
+     */
     int txCount(long blockNo) throws ApiException;
 
-    /** Returns the number of transactions sent from an address */
+    /**
+     * Returns the number of transactions sent from an address
+     * eth_getTransactionCount
+     */
     int txSendCount(String address) throws ApiException;
 
-    //TODO implement
-    /** Creates new message call transaction or a contract creation for signed transactions */
-    boolean txSendRaw(String hexEncodedTx) throws ApiException;
+    /**
+     * Creates new message call transaction or a contract creation for signed transactions
+     * eth_sendRawTransaction
+     */
+    @NotNull Optional<String> txSendRaw(String hexEncodedTx) throws ApiException;
+
+    /**
+     * Returns the receipt of a transaction by transaction hash
+     * eth_getTransactionReceipt
+     */
+    @NotNull Optional<TxInfoProxy> txReceipt(String txhash);
 
-    /** Executes a new message call immediately without creating a transaction on the block chain */
-    @NotNull String call(String address, String data) throws ApiException;
+    /**
+     * Executes a new message call immediately without creating a transaction on the block chain
+     * eth_call
+     */
+    @NotNull Optional<String> call(String address, String data) throws ApiException;
 
-    /** Returns code at a given address */
-    @NotNull String code(String address) throws ApiException;
+    /**
+     * Returns code at a given address
+     * eth_getCode
+     */
+    @NotNull Optional<String> code(String address) throws ApiException;
 
     /**
      * (**experimental)
      * Returns the value from a storage position at a given address
+     * eth_getStorageAt
      */
-    @NotNull String storageAt(String address, long position) throws ApiException;
+    @NotNull Optional<String> storageAt(String address, long position) throws ApiException;
 
-    /** Returns the current price per gas in wei */
+    /**
+     * Returns the current price per gas in wei
+     * eth_gasPrice
+     */
     @NotNull BigInteger gasPrice() throws ApiException;
 
     /**
      * Makes a call or transaction, which won't be added to the blockchain and returns the used gas,
      * which can be used for estimating the used gas
+     * eth_estimateGas
      */
     @NotNull BigInteger gasEstimated() throws ApiException;
     @NotNull BigInteger gasEstimated(String hexData) throws ApiException;

src/main/java/io/api/etherscan/core/impl/BasicProvider.java

@@ -1,16 +1,17 @@
 package io.api.etherscan.core.impl;
 
 import com.google.gson.Gson;
+import io.api.etherscan.error.NoResponseException;
 import io.api.etherscan.error.ParseException;
 import io.api.etherscan.executor.IHttpExecutor;
 import io.api.etherscan.manager.IQueueManager;
+import io.api.etherscan.util.BasicUtils;
 
 /**
  * Base provider for API Implementations
  *
- * @see EtherScanApi
- *
  * @author GoodforGod
+ * @see EtherScanApi
  * @since 28.10.2018
  */
 abstract class BasicProvider {
@@ -24,6 +25,7 @@ abstract class BasicProvider {
     private final String baseUrl;
     private final IHttpExecutor executor;
     private final IQueueManager queue;
+    private final Gson gson;
 
     BasicProvider(final IQueueManager queue,
                   final String module,
@@ -33,11 +35,12 @@ abstract class BasicProvider {
         this.module = "&module=" + module;
         this.baseUrl = baseUrl;
         this.executor = executor;
+        this.gson = new Gson();
     }
 
     private <T> T convert(final String json, final Class<T> tClass) {
         try {
-            return new Gson().fromJson(json, tClass);
+            return gson.fromJson(json, tClass);
         } catch (Exception e) {
             throw new ParseException(e.getMessage(), e.getCause());
         }
@@ -46,10 +49,24 @@ private <T> T convert(final String json, final Class<T> tClass) {
     private String getRequest(final String urlParameters) {
         queue.takeTurn();
         final String url = baseUrl + module + urlParameters;
-        return executor.get(url);
+        final String result = executor.get(url);
+        if (BasicUtils.isEmpty(result))
+            throw new NoResponseException("Server returned null value for GET request at URL - " + url);
+
+        return result;
+    }
+
+    private String postRequest(final String urlParameters, final String dataToPost) {
+        queue.takeTurn();
+        final String url = baseUrl + module + urlParameters;
+        return executor.post(url, dataToPost);
     }
 
     <T> T getRequest(final String urlParameters, final Class<T> tClass) {
         return convert(getRequest(urlParameters), tClass);
     }
+
+    <T> T postRequest(final String urlParameters, final String dataToPost, final Class<T> tClass) {
+        return convert(postRequest(urlParameters, dataToPost), tClass);
+    }
 }

src/main/java/io/api/etherscan/core/impl/BlockApiProvider.java

@@ -35,6 +35,7 @@ public class BlockApiProvider extends BasicProvider implements IBlockApi {
     public Optional<UncleBlock> uncles(long blockNumber) {
         final String urlParam = ACT_BLOCK_PARAM + BLOCKNO_PARAM + blockNumber;
         final UncleBlockResponseTO response = getRequest(urlParam, UncleBlockResponseTO.class);
+
         BasicUtils.validateTxResponse(response);
 
         return (response.getResult() == null || response.getResult().isEmpty())

src/main/java/io/api/etherscan/core/impl/ProxyApiProvider.java

@@ -2,13 +2,16 @@
 
 import io.api.etherscan.core.IProxyApi;
 import io.api.etherscan.error.ApiException;
+import io.api.etherscan.error.EtherScanException;
 import io.api.etherscan.error.InvalidDataHexException;
 import io.api.etherscan.executor.IHttpExecutor;
 import io.api.etherscan.manager.IQueueManager;
 import io.api.etherscan.model.proxy.BlockProxy;
+import io.api.etherscan.model.proxy.TxInfoProxy;
 import io.api.etherscan.model.proxy.TxProxy;
 import io.api.etherscan.model.proxy.utility.BlockProxyTO;
 import io.api.etherscan.model.proxy.utility.StringProxyTO;
+import io.api.etherscan.model.proxy.utility.TxInfoProxyTO;
 import io.api.etherscan.model.proxy.utility.TxProxyTO;
 import io.api.etherscan.util.BasicUtils;
 import org.jetbrains.annotations.NotNull;
@@ -112,7 +115,7 @@ public Optional<TxProxy> tx(final long blockNo, final long index) throws ApiExce
     @Override
     public int txCount(final long blockNo) throws ApiException {
         final long compensatedBlockNo = BasicUtils.compensateMinBlock(blockNo);
-        final String urlParams = ACT_TX_COUNT_PARAM + TAG_PARAM + compensatedBlockNo;
+        final String urlParams = ACT_BLOCKTX_COUNT_PARAM + TAG_PARAM + compensatedBlockNo;
         final StringProxyTO response = getRequest(urlParams, StringProxyTO.class);
         return Integer.valueOf(response.getResult());
     }
@@ -121,52 +124,73 @@ public int txCount(final long blockNo) throws ApiException {
     public int txSendCount(final String address) throws ApiException {
         BasicUtils.validateAddress(address);
 
-        final String urlParams = ACT_TX_BY_HASH_PARAM + ADDRESS_PARAM + address + TAG_LAST_PARAM;
+        final String urlParams = ACT_TX_COUNT_PARAM + ADDRESS_PARAM + address + TAG_LAST_PARAM;
         final StringProxyTO response = getRequest(urlParams, StringProxyTO.class);
         return (int) BasicUtils.parseHex(response.getResult());
     }
 
-    //TODO need postRequest executor implementation
     @Override
-    public boolean txSendRaw(final String hexEncodedTx) throws ApiException {
-        return false;
+    @NotNull
+    public Optional<String> txSendRaw(final String hexEncodedTx) throws ApiException {
+        if(BasicUtils.isNotHex(hexEncodedTx))
+            throw new InvalidDataHexException("Data is not encoded in hex format - " + hexEncodedTx);
+
+        final String urlParams = ACT_SEND_RAW_TX_PARAM + HEX_PARAM + hexEncodedTx;
+        final StringProxyTO response = getRequest(urlParams, StringProxyTO.class);
+        if(response.getError() != null)
+            throw new EtherScanException("Error occurred with code " + response.getError().getCode()
+                    + " with message " + response.getError().getMessage());
+
+        return (BasicUtils.isEmpty(response.getResult()))
+                ? Optional.empty()
+                : Optional.of(response.getResult());
+    }
+
+    @NotNull
+    @Override
+    public Optional<TxInfoProxy> txReceipt(final String txhash) {
+        BasicUtils.validateTxHash(txhash);
+
+        final String urlParams = ACT_TX_RECEIPT_PARAM + TXHASH_PARAM + txhash;
+        final TxInfoProxyTO response = getRequest(urlParams, TxInfoProxyTO.class);
+        return Optional.ofNullable(response.getResult());
     }
 
     @NotNull
     @Override
-    public String call(final String address, final String data) throws ApiException {
+    public Optional<String> call(final String address, final String data) throws ApiException {
         BasicUtils.validateAddress(address);
 
         final String urlParams = ACT_CALL_PARAM + TO_PARAM + address + DATA_PARAM + data + TAG_LAST_PARAM;
         final StringProxyTO response = getRequest(urlParams, StringProxyTO.class);
         return (BasicUtils.isEmpty(response.getResult()))
-                ? ""
-                : response.getResult();
+                ? Optional.empty()
+                : Optional.of(response.getResult());
     }
 
     @NotNull
     @Override
-    public String code(final String address) throws ApiException {
+    public Optional<String> code(final String address) throws ApiException {
         BasicUtils.validateAddress(address);
 
         final String urlParams = ACT_CODE_PARAM + ADDRESS_PARAM + address + TAG_LAST_PARAM;
         final StringProxyTO response = getRequest(urlParams, StringProxyTO.class);
         return (BasicUtils.isEmpty(response.getResult()))
-                ? ""
-                : response.getResult();
+                ? Optional.empty()
+                : Optional.of(response.getResult());
     }
 
     @NotNull
     @Override
-    public String storageAt(final String address, final long position) throws ApiException {
+    public Optional<String> storageAt(final String address, final long position) throws ApiException {
         BasicUtils.validateAddress(address);
         final long compPosition = BasicUtils.compensateMinBlock(position);
 
         final String urlParams = ACT_STORAGEAT_PARAM + ADDRESS_PARAM + address + POSITION_PARAM + compPosition + TAG_LAST_PARAM;
         final StringProxyTO response = getRequest(urlParams, StringProxyTO.class);
         return (BasicUtils.isEmpty(response.getResult()))
-                ? ""
-                : response.getResult();
+                ? Optional.empty()
+                : Optional.of(response.getResult());
     }
 
     @NotNull

src/main/java/io/api/etherscan/error/NoResponseException.java

@@ -0,0 +1,14 @@
+package io.api.etherscan.error;
+
+/**
+ * ! NO DESCRIPTION !
+ *
+ * @author GoodforGod
+ * @since 03.11.2018
+ */
+public class NoResponseException extends ApiException {
+
+    public NoResponseException(String message) {
+        super(message);
+    }
+}

src/main/java/io/api/etherscan/executor/IHttpExecutor.java

@@ -1,7 +1,7 @@
 package io.api.etherscan.executor;
 
 /**
- * ! NO DESCRIPTION !
+ * Http Client interface
  *
  * @author GoodforGod
  * @since 31.10.2018
@@ -15,4 +15,13 @@ public interface IHttpExecutor {
      * @return result as string
      */
     String get(String url);
+
+    /**
+     * Performs a Http POST request
+     *
+     * @param url as string
+     * @param data to post
+     * @return result as string
+     */
+    String post(String url, String data);
 }