netinfo: allow setting an outbound-only peer list

by passing an additional argument of "outonly" or "o".

This has been requested in order to keep the output within screen limits when running -netinfo
as a live dashboard, i.e. with `watch`.

Also allow passing "h" in addition to "help" to see the help documentation.

Author: jonatack

src/bitcoin-cli.cpp

@@ -394,6 +394,7 @@ class NetinfoRequestHandler : public BaseRequestHandler
     bool DetailsRequested() const { return m_details_level > 0 && m_details_level < 5; }
     bool IsAddressSelected() const { return m_details_level == 2 || m_details_level == 4; }
     bool IsVersionSelected() const { return m_details_level == 3 || m_details_level == 4; }
+    bool m_outbound_only_selected{false};
     bool m_is_asmap_on{false};
     size_t m_max_addr_length{0};
     size_t m_max_addr_processed_length{5};
@@ -479,7 +480,16 @@ class NetinfoRequestHandler : public BaseRequestHandler
             if (ParseUInt8(args.at(0), &n)) {
                 m_details_level = std::min(n, NETINFO_MAX_LEVEL);
             } else {
-                throw std::runtime_error(strprintf("invalid -netinfo argument: %s\nFor more information, run: bitcoin-cli -netinfo help", args.at(0)));
+                throw std::runtime_error(strprintf("invalid -netinfo level argument: %s\nFor more information, run: bitcoin-cli -netinfo help", args.at(0)));
+            }
+            if (args.size() > 1) {
+                if (std::string_view s{args.at(1)}; n && (s == "o" || s == "outonly")) {
+                    m_outbound_only_selected = true;
+                } else if (n) {
+                    throw std::runtime_error(strprintf("invalid -netinfo outonly argument: %s\nFor more information, run: bitcoin-cli -netinfo help", args.at(1)));
+                } else {
+                    throw std::runtime_error(strprintf("invalid -netinfo outonly argument: %s\nThe outonly argument is only valid for details levels higher than 0. For more information, run: bitcoin-cli -netinfo help", args.at(1)));
+                }
             }
         }
         UniValue result(UniValue::VARR);
@@ -514,6 +524,7 @@ class NetinfoRequestHandler : public BaseRequestHandler
             ++m_counts.at(2).at(NETWORKS.size());           // total overall
             if (conn_type == "block-relay-only") ++m_block_relay_peers_count;
             if (conn_type == "manual") ++m_manual_peers_count;
+            if (m_outbound_only_selected && !is_outbound) continue;
             if (DetailsRequested()) {
                 // Push data for this peer to the peers vector.
                 const int peer_id{peer["id"].getInt<int>()};
@@ -648,14 +659,15 @@ class NetinfoRequestHandler : public BaseRequestHandler
     }
 
     const std::string m_help_doc{
-        "-netinfo level|\"help\" \n\n"
+        "-netinfo level|outonly|help\n\n"
         "Returns a network peer connections dashboard with information from the remote server.\n"
         "This human-readable interface will change regularly and is not intended to be a stable API.\n"
         "Under the hood, -netinfo fetches the data by calling getpeerinfo and getnetworkinfo.\n"
-        + strprintf("An optional integer argument from 0 to %d can be passed for different peers listings; values from %d to 255 are parsed as %d.\n", NETINFO_MAX_LEVEL, NETINFO_MAX_LEVEL, NETINFO_MAX_LEVEL) +
-        "Pass \"help\" to see this detailed help documentation.\n"
-        "If more than one argument is passed, only the first one is read and parsed.\n"
-        "Suggestion: use with the Linux watch(1) command for a live dashboard; see example below.\n\n"
+        + strprintf("An optional argument from 0 to %d can be passed for different peers listings; values above %d up to 255 are parsed as %d.\n", NETINFO_MAX_LEVEL, NETINFO_MAX_LEVEL, NETINFO_MAX_LEVEL) +
+        "If that argument is passed, an optional additional \"outonly\" argument may be passed to obtain the listing with outbound peers only.\n"
+        "Pass \"help\" or \"h\" to see this detailed help documentation.\n"
+        "If more than two arguments are passed, only the first two are read and parsed.\n"
+        "Suggestion: use -netinfo with the Linux watch(1) command for a live dashboard; see example below.\n\n"
         "Arguments:\n"
         + strprintf("1. level (integer 0-%d, optional)  Specify the info level of the peers dashboard (default 0):\n", NETINFO_MAX_LEVEL) +
         "                                  0 - Peer counts for each reachable network as well as for block relay peers\n"
@@ -664,7 +676,9 @@ class NetinfoRequestHandler : public BaseRequestHandler
         "                                  2 - Like 1 but with an address column\n"
         "                                  3 - Like 1 but with a version column\n"
         "                                  4 - Like 1 but with both address and version columns\n"
-        "2. help (string \"help\", optional) Print this help documentation instead of the dashboard.\n\n"
+        "2. outonly (\"outonly\" or \"o\", optional) Return the peers listing with outbound peers only, i.e. to save screen space\n"
+        "                                        when a node has many inbound peers. Only valid if a level is passed.\n\n"
+        "help (\"help\" or \"h\", optional) Print this help documentation instead of the dashboard.\n\n"
         "Result:\n\n"
         + strprintf("* The peers listing in levels 1-%d displays all of the peers sorted by direction and minimum ping time:\n\n", NETINFO_MAX_LEVEL) +
         "  Column   Description\n"
@@ -717,6 +731,8 @@ class NetinfoRequestHandler : public BaseRequestHandler
         "> bitcoin-cli -netinfo 1\n\n"
         "Full dashboard\n"
         + strprintf("> bitcoin-cli -netinfo %d\n\n", NETINFO_MAX_LEVEL) +
+        "Full dashboard, but with outbound peers only\n"
+        + strprintf("> bitcoin-cli -netinfo %d outonly\n\n", NETINFO_MAX_LEVEL) +
         "Full live dashboard, adjust --interval or --no-title as needed (Linux)\n"
         + strprintf("> watch --interval 1 --no-title bitcoin-cli -netinfo %d\n\n", NETINFO_MAX_LEVEL) +
         "See this help\n"
@@ -1243,7 +1259,7 @@ static int CommandLineRPC(int argc, char *argv[])
         if (gArgs.IsArgSet("-getinfo")) {
             rh.reset(new GetinfoRequestHandler());
         } else if (gArgs.GetBoolArg("-netinfo", false)) {
-            if (!args.empty() && args.at(0) == "help") {
+            if (!args.empty() && (args.at(0) == "h" || args.at(0) == "help")) {
                 tfm::format(std::cout, "%s\n", NetinfoRequestHandler().m_help_doc);
                 return 0;
             }