[FAB-13777] Fix private data base64 instructions

Document how to base64 encode in private data tutorial.

Change-Id: I0dc89fc18afd3aa79fdcd6695a9dc8139b689f6c
Signed-off-by: David Enyeart <enyeart@us.ibm.com>

Author: denyeart

docs/source/private_data_tutorial.rst

@@ -435,11 +435,12 @@ submit a request to add a marble:
  as transient data will not be persisted in the transaction in order to keep
  the data private. Transient data is passed as binary data and therefore when
  using CLI it must be base64 encoded. We use an environment variable
- to capture the base64 encoded value.
+ to capture the base64 encoded value, and use ``tr`` command to strip off the
+ problematic newline characters that linux base64 command adds.
 
  .. code:: bash
 
-   export MARBLE=$(echo -n "{\"name\":\"marble1\",\"color\":\"blue\",\"size\":35,\"owner\":\"tom\",\"price\":99}" | base64)
+   export MARBLE=$(echo -n "{\"name\":\"marble1\",\"color\":\"blue\",\"size\":35,\"owner\":\"tom\",\"price\":99}" | base64 | tr -d \\n)
    peer chaincode invoke -o orderer.example.com:7050 --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem -C mychannel -n marblesp -c '{"Args":["initMarble"]}'  --transient "{\"marble\":\"$MARBLE\"}"
 
  You should see results similar to:
@@ -700,7 +701,7 @@ price private data is purged.
 
  .. code:: bash
 
-    export MARBLE=$(echo -n "{\"name\":\"marble2\",\"color\":\"blue\",\"size\":35,\"owner\":\"tom\",\"price\":99}" | base64)
+    export MARBLE=$(echo -n "{\"name\":\"marble2\",\"color\":\"blue\",\"size\":35,\"owner\":\"tom\",\"price\":99}" | base64 | tr -d \\n)
     peer chaincode invoke -o orderer.example.com:7050 --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem -C mychannel -n marblesp -c '{"Args":["initMarble"]}' --transient "{\"marble\":\"$MARBLE\"}"
 
  Switch back to the Terminal window and view the private data logs for this peer
@@ -729,7 +730,7 @@ price private data is purged.
 
  .. code:: bash
 
-    export MARBLE_OWNER=$(echo -n "{\"name\":\"marble2\",\"owner\":\"joe\"}" | base64)
+    export MARBLE_OWNER=$(echo -n "{\"name\":\"marble2\",\"owner\":\"joe\"}" | base64 | tr -d \\n)
     peer chaincode invoke -o orderer.example.com:7050 --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem -C mychannel -n marblesp -c '{"Args":["transferMarble"]}' --transient "{\"marble_owner\":\"$MARBLE_OWNER\"}"
 
  Switch back to the Terminal window and view the private data logs for this peer
@@ -757,7 +758,7 @@ price private data is purged.
 
  .. code:: bash
 
-    export MARBLE_OWNER=$(echo -n "{\"name\":\"marble2\",\"owner\":\"tom\"}" | base64)
+    export MARBLE_OWNER=$(echo -n "{\"name\":\"marble2\",\"owner\":\"tom\"}" | base64 | tr -d \\n)
     peer chaincode invoke -o orderer.example.com:7050 --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem -C mychannel -n marblesp -c '{"Args":["transferMarble"]}' --transient "{\"marble_owner\":\"$MARBLE_OWNER\"}"
 
  Switch back to the Terminal window and view the private data logs for this peer
@@ -786,7 +787,7 @@ price private data is purged.
 
  .. code:: bash
 
-    export MARBLE_OWNER=$(echo -n "{\"name\":\"marble2\",\"owner\":\"jerry\"}" | base64)
+    export MARBLE_OWNER=$(echo -n "{\"name\":\"marble2\",\"owner\":\"jerry\"}" | base64 | tr -d \\n)
     peer chaincode invoke -o orderer.example.com:7050 --tls --cafile /opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/ordererOrganizations/example.com/orderers/orderer.example.com/msp/tlscacerts/tlsca.example.com-cert.pem -C mychannel -n marblesp -c '{"Args":["transferMarble"]}' --transient "{\"marble_owner\":\"$MARBLE_OWNER\"}"
 
  Switch back to the Terminal window and view the private data logs for this peer