Improve JSON logging

src/ripple/consensus/Consensus.h

@@ -1020,8 +1020,9 @@ Consensus<Adaptor>::checkLedger()
                         << ", "
                         << " mode=" << to_string(mode_.get());
         JLOG(j_.warn()) << prevLedgerID_ << " to " << netLgr;
-        JLOG(j_.warn()) << previousLedger_.getJson();
-        JLOG(j_.debug()) << "State on consensus change " << getJson(true);
+        JLOG(j_.warn()) << Json::Compact{previousLedger_.getJson()};
+        JLOG(j_.debug()) << "State on consensus change "
+                         << Json::Compact{getJson(true)};
         handleWrongLedger(netLgr);
     }
     else if (previousLedger_.id() != prevLedgerID_)
@@ -1434,7 +1435,7 @@ Consensus<Adaptor>::haveConsensus()
     if (result_->state == ConsensusState::MovedOn)
     {
         JLOG(j_.error()) << "Unable to reach consensus";
-        JLOG(j_.error()) << getJson(true);
+        JLOG(j_.error()) << Json::Compact{getJson(true)};
     }
 
     return true;

src/ripple/consensus/DisputedTx.h

@@ -25,6 +25,7 @@
 #include <ripple/basics/base_uint.h>
 #include <ripple/beast/utility/Journal.h>
 #include <ripple/consensus/ConsensusParms.h>
+#include <ripple/json/json_writer.h>
 #include <ripple/protocol/Serializer.h>
 #include <ripple/protocol/UintTypes.h>
 #include <memory>
@@ -239,14 +240,14 @@ DisputedTx<Tx_t, NodeID_t>::updateVote(
         JLOG(j_.info()) << "No change (" << (ourVote_ ? "YES" : "NO")
                         << ") : weight " << weight << ", percent "
                         << percentTime;
-        JLOG(j_.debug()) << getJson();
+        JLOG(j_.debug()) << Json::Compact{getJson()};
         return false;
     }
 
     ourVote_ = newPosition;
     JLOG(j_.debug()) << "We now vote " << (ourVote_ ? "YES" : "NO") << " on "
                      << tx_.id();
-    JLOG(j_.debug()) << getJson();
+    JLOG(j_.debug()) << Json::Compact{getJson()};
     return true;
 }
 

src/ripple/json/impl/json_writer.cpp

@@ -743,87 +743,4 @@ std::ostream& operator<< ( std::ostream& sout, const Value& root )
     return sout;
 }
 
-//------------------------------------------------------------------------------
-
-namespace detail {
-
-inline
-void
-write_string (write_t write, std::string const& s)
-{
-    write(s.data(), s.size());
-}
-
-void
-write_value (write_t write, Value const& value)
-{
-    switch (value.type())
-    {
-    case nullValue:
-        write("null", 4);
-        break;
-
-    case intValue:
-        write_string(write, valueToString(value.asInt()));
-        break;
-
-    case uintValue:
-        write_string(write, valueToString(value.asUInt()));
-        break;
-
-    case realValue:
-        write_string(write, valueToString(value.asDouble()));
-        break;
-
-    case stringValue:
-        write_string(write, valueToQuotedString(value.asCString()));
-        break;
-
-    case booleanValue:
-        write_string(write, valueToString(value.asBool()));
-        break;
-
-    case arrayValue:
-    {
-        write("[", 1);
-        int const size = value.size();
-        for (int index = 0; index < size; ++index)
-        {
-            if (index > 0)
-                write(",", 1);
-            write_value(write, value[index]);
-        }
-        write("]", 1);
-        break;
-    }
-
-    case objectValue:
-    {
-        Value::Members const members = value.getMemberNames();
-        write("{", 1);
-        for (auto it = members.begin(); it != members.end(); ++it)
-        {
-            std::string const& name = *it;
-            if (it != members.begin())
-                write(",", 1);
-
-            write_string(write, valueToQuotedString(name.c_str()));
-            write(":", 1);
-            write_value(write, value[name]);
-        }
-        write("}", 1);
-        break;
-    }
-    }
-}
-
-} // detail
-
-void
-stream (Json::Value const& jv, write_t write)
-{
-    detail::write_value(write, jv);
-    write("\n", 1);
-}
-
 } // namespace Json

src/ripple/json/json_value.h

@@ -606,14 +606,6 @@ class ValueIterator : public ValueIteratorBase
     }
 };
 
-//------------------------------------------------------------------------------
-
-using write_t = std::function<void(void const*, std::size_t)>;
-
-/** Stream compact JSON to the specified function. */
-void
-stream (Json::Value const& jv, write_t write);
-
 } // namespace Json
 
 

src/ripple/json/json_writer.h

@@ -22,6 +22,7 @@
 
 #include <ripple/json/json_forwards.h>
 #include <ripple/json/json_value.h>
+#include <ostream>
 #include <vector>
 
 namespace Json
@@ -175,8 +176,137 @@ std::string valueToQuotedString ( const char* value );
 /// \see Json::operator>>()
 std::ostream& operator<< ( std::ostream&, const Value& root );
 
-} // namespace Json
+//------------------------------------------------------------------------------
+
+// Helpers for stream
+namespace detail {
+
+template <class Write>
+void
+write_string(Write const& write, std::string const& s)
+{
+    write(s.data(), s.size());
+}
+
+template <class Write>
+void
+write_value(Write const& write, Value const& value)
+{
+    switch (value.type())
+    {
+        case nullValue:
+            write("null", 4);
+            break;
+
+        case intValue:
+            write_string(write, valueToString(value.asInt()));
+            break;
+
+        case uintValue:
+            write_string(write, valueToString(value.asUInt()));
+            break;
+
+        case realValue:
+            write_string(write, valueToString(value.asDouble()));
+            break;
+
+        case stringValue:
+            write_string(write, valueToQuotedString(value.asCString()));
+            break;
+
+        case booleanValue:
+            write_string(write, valueToString(value.asBool()));
+            break;
+
+        case arrayValue:
+        {
+            write("[", 1);
+            int const size = value.size();
+            for (int index = 0; index < size; ++index)
+            {
+                if (index > 0)
+                    write(",", 1);
+                write_value(write, value[index]);
+            }
+            write("]", 1);
+            break;
+        }
+
+        case objectValue:
+        {
+            Value::Members const members = value.getMemberNames();
+            write("{", 1);
+            for (auto it = members.begin(); it != members.end(); ++it)
+            {
+                std::string const& name = *it;
+                if (it != members.begin())
+                    write(",", 1);
+
+                write_string(write, valueToQuotedString(name.c_str()));
+                write(":", 1);
+                write_value(write, value[name]);
+            }
+            write("}", 1);
+            break;
+        }
+    }
+}
+
+}  // namespace detail
 
+/** Stream compact JSON to the specified function.
+
+    @param jv The Json::Value to write
+    @param write Invocable with signature void(void const*, std::size_t) that
+                 is called when output should be written to the stream.
+*/
+template <class Write>
+void
+stream(Json::Value const& jv, Write const& write)
+{
+    detail::write_value(write, jv);
+    write("\n", 1);
+}
+
+/** Decorator for streaming out compact json
+
+    Use
+
+        Json::Value jv;
+        out << Json::Compact{jv}
+
+    to write a single-line, compact version of `jv` to the stream, rather
+    than the styled format that comes from undecorated streaming.
+*/
+class Compact
+{
+    Json::Value jv_;
+
+public:
+    /** Wrap a Json::Value for compact streaming
+
+        @param jv The Json::Value to stream
+
+        @note For now, we do not support wrapping lvalues to avoid
+              potentially costly copies. If we find a need, we can consider
+              adding support for compact lvalue streaming in the future.
+    */
+    Compact(Json::Value&& jv) : jv_{std::move(jv)}
+    {
+    }
+
+    friend std::ostream&
+    operator<<(std::ostream& o, Compact const& cJv)
+    {
+        detail::write_value(
+            [&o](void const* data, std::size_t n) {
+                o.write(static_cast<char const*>(data), n);
+            },
+            cJv.jv_);
+        return o;
+    }
+};
 
+}  // namespace Json
 
 #endif // JSON_WRITER_H_INCLUDED

src/ripple/rpc/impl/ServerHandlerImp.h

@@ -27,6 +27,7 @@
 #include <ripple/server/WSSession.h>
 #include <ripple/rpc/RPCHandler.h>
 #include <ripple/app/main/CollectorManager.h>
+#include <ripple/json/Output.h>
 #include <map>
 #include <mutex>
 #include <vector>

src/ripple/rpc/impl/WSInfoSub.h

@@ -23,8 +23,7 @@
 #include <ripple/server/WSSession.h>
 #include <ripple/net/InfoSub.h>
 #include <ripple/beast/net/IPAddressConversion.h>
-#include <ripple/json/Output.h>
-#include <ripple/json/to_string.h>
+#include <ripple/json/json_writer.h>
 #include <ripple/rpc/Role.h>
 #include <memory>
 #include <string>
@@ -75,7 +74,7 @@ class WSInfoSub : public InfoSub
         if(! sp)
             return;
         beast::multi_buffer sb;
-        stream(jv,
+        Json::stream(jv,
             [&](void const* data, std::size_t n)
             {
                 sb.commit(boost::asio::buffer_copy(

src/test/json/json_value_test.cpp

@@ -20,6 +20,7 @@
 #include <BeastConfig.h>
 #include <ripple/json/json_value.h>
 #include <ripple/json/json_reader.h>
+#include <ripple/json/json_writer.h>
 #include <ripple/beast/unit_test.h>
 #include <ripple/beast/type_name.h>
 
@@ -222,6 +223,32 @@ struct json_value_test : beast::unit_test::suite
         testGreaterThan ("big");
     }
 
+    void test_compact ()
+    {
+        Json::Value j;
+        Json::Reader r;
+        char const* s ("{\"array\":[{\"12\":23},{},null,false,0.5]}");
+
+        auto countLines = [](std::string const & s)
+        {
+            return 1 + std::count_if(s.begin(), s.end(), [](char c){
+                return c == '\n';
+            });
+        };
+
+        BEAST_EXPECT(r.parse(s,j));
+        {
+            std::stringstream ss;
+            ss << j;
+            BEAST_EXPECT(countLines(ss.str()) > 1);
+        }
+        {
+            std::stringstream ss;
+            ss << Json::Compact(std::move(j));
+            BEAST_EXPECT(countLines(ss.str()) == 1);
+        }
+    }
+
     void run ()
     {
         test_bool ();
@@ -230,6 +257,7 @@ struct json_value_test : beast::unit_test::suite
         test_copy ();
         test_move ();
         test_comparisons ();
+        test_compact ();
     }
 };