Make rpcauth help message clearer, add example in example .conf

contrib/debian/examples/bitcoin.conf

@@ -67,9 +67,30 @@
 # This option can be specified multiple times (default: bind to all interfaces)
 #rpcbind=<addr>
 
-# You must set rpcuser and rpcpassword to secure the JSON-RPC api
+# If no rpcpassword is set, rpc cookie auth is sought. The default `-rpccookiefile` name
+# is .cookie and found in the `-datadir` being used for bitcoind. This option is typically used
+# when the server and client are run as the same user.
+#
+# If not, you must set rpcuser and rpcpassword to secure the JSON-RPC api. The first
+# method(DEPRECATED) is to set this pair for the server and client:
 #rpcuser=Ulysseys
 #rpcpassword=YourSuperGreatPasswordNumber_DO_NOT_USE_THIS_OR_YOU_WILL_GET_ROBBED_385593
+#
+# The second method `rpcauth` can be added to server startup argument. It is set at intialization time
+# using the output from the script in share/rpcuser/rpcuser.py after providing a username:
+#
+# ./share/rpcuser/rpcuser.py alice
+# String to be appended to bitcoin.conf:
+# rpcauth=alice:f7efda5c189b999524f151318c0c86$d5b51b3beffbc02b724e5d095828e0bc8b2456e9ac8757ae3211a5d9b16a22ae
+# Your password:
+# DONT_USE_THIS_YOU_WILL_GET_ROBBED_8ak1gI25KFTvjovL3gAM967mies3E=
+#
+# On client-side, you add the normal user/password pair to send commands:
+#rpcuser=alice
+#rpcpassword=DONT_USE_THIS_YOU_WILL_GET_ROBBED_8ak1gI25KFTvjovL3gAM967mies3E=
+#
+# You can even add multiple entries of these to the server conf file, and client can use any of them:
+# rpcauth=bob:b2dd077cb54591a2f3139e69a897ac$4e71f08d48b4347cf8eff3815c0e25ae2e9a4340474079f55705f40574f4ec99
 
 # How many seconds bitcoin will wait for a complete RPC HTTP request.
 # after the HTTP connection is established. 

src/init.cpp

@@ -484,7 +484,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-rpccookiefile=<loc>", _("Location of the auth cookie (default: data dir)"));
     strUsage += HelpMessageOpt("-rpcuser=<user>", _("Username for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcpassword=<pw>", _("Password for JSON-RPC connections"));
-    strUsage += HelpMessageOpt("-rpcauth=<userpw>", _("Username and hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcuser. This option can be specified multiple times"));
+    strUsage += HelpMessageOpt("-rpcauth=<userpw>", _("Username and hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcuser. The client then connects normally using the rpcuser=<USERNAME>/rpcpassword=<PASSWORD> pair of arguments. This option can be specified multiple times"));
     strUsage += HelpMessageOpt("-rpcport=<port>", strprintf(_("Listen for JSON-RPC connections on <port> (default: %u or testnet: %u)"), BaseParams(CBaseChainParams::MAIN).RPCPort(), BaseParams(CBaseChainParams::TESTNET).RPCPort()));
     strUsage += HelpMessageOpt("-rpcallowip=<ip>", _("Allow JSON-RPC connections from specified source. Valid for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. 1.2.3.4/24). This option can be specified multiple times"));
     strUsage += HelpMessageOpt("-rpcthreads=<n>", strprintf(_("Set the number of threads to service RPC calls (default: %d)"), DEFAULT_HTTP_THREADS));