FAB-5368 No means to get channel config

FAB-5368 No means to get channel config bytes for update.

PS 4: Fix up javadoc. Do a sanity check in End2endAndBackAgainIT
       for getChannelConfigurationBytes

Change-Id: Ia7dd6de821e507ac37db17454072d85b86cb9664
Signed-off-by: rickr <cr22rc@gmail.com>

src/main/java/org/hyperledger/fabric/sdk/Channel.java

@@ -822,6 +822,13 @@ private Map<String, MSP> traverseConfigGroupsMSP(String name, ConfigGroup config
         return msps;
     }
 
+    /**
+     * Provide the Channel's latest raw Configuration Block.
+     *
+     * @return Channel configuration block.
+     * @throws TransactionException
+     */
+
     private Block getConfigurationBlock() throws TransactionException {
 
         logger.debug(format("getConfigurationBlock for channel %s", name));
@@ -874,6 +881,37 @@ private Block getConfigurationBlock() throws TransactionException {
 
     }
 
+    /**
+     * Channel Configuration bytes. Bytes that can be used with configtxlator tool to upgrade the channel.
+     * Convert to Json for editing  with:
+     * {@code
+     *
+     * curl -v   POST --data-binary @fooConfig http://host/protolator/decode/common.Config
+     *
+     * }
+     * See http://hyperledger-fabric.readthedocs.io/en/latest/configtxlator.html
+     *
+     * @return Channel configuration bytes.
+     * @throws TransactionException
+     */
+
+    public byte[] getChannelConfigurationBytes() throws TransactionException {
+        try {
+            final Block configBlock = getConfigurationBlock();
+
+            Envelope envelopeRet = Envelope.parseFrom(configBlock.getData().getData(0));
+
+            Payload payload = Payload.parseFrom(envelopeRet.getPayload());
+
+            ConfigEnvelope configEnvelope = ConfigEnvelope.parseFrom(payload.getData());
+            return configEnvelope.getConfig().toByteArray();
+
+        } catch (Exception e) {
+            throw new TransactionException(e);
+        }
+
+    }
+
     private Block getBlockByNumber(final long number) throws TransactionException {
 
         logger.trace(format("getConfigurationBlock for channel %s", name));

src/test/java/org/hyperledger/fabric/sdkintegration/End2endAndBackAgainIT.java

@@ -26,6 +26,7 @@
 import java.util.concurrent.CompletionException;
 import java.util.concurrent.TimeUnit;
 
+import org.hyperledger.fabric.protos.common.Configtx;
 import org.hyperledger.fabric.protos.peer.Query.ChaincodeInfo;
 import org.hyperledger.fabric.sdk.BlockEvent;
 import org.hyperledger.fabric.sdk.ChaincodeEndorsementPolicy;
@@ -55,6 +56,7 @@
 
 import static java.lang.String.format;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.fail;
 
 /**
@@ -515,6 +517,16 @@ private Channel reconstructChannel(String name, HFClient client, SampleOrg sampl
 
         newChannel.initialize();
 
+        //Just see if we can get channelConfiguration. Not required for the rest of scenario but should work.
+        final byte[] channelConfigurationBytes = newChannel.getChannelConfigurationBytes();
+        Configtx.Config channelConfig = Configtx.Config.parseFrom(channelConfigurationBytes);
+        assertNotNull(channelConfig);
+        Configtx.ConfigGroup channelGroup = channelConfig.getChannelGroup();
+        assertNotNull(channelGroup);
+        Map<String, Configtx.ConfigGroup> groupsMap = channelGroup.getGroupsMap();
+        assertNotNull(groupsMap.get("Orderer"));
+        assertNotNull(groupsMap.get("Application"));
+
         //Before return lets see if we have the chaincode on the peers that we expect from End2endIT
         //And if they were instantiated too.