Merge bitcoin-core/gui#416: Add RPC setting

bd5c826a9630f41255497e0c9a0f1872b5ab78d5 gui: add RPC setting (Sjors Provoost)

Pull request description:

  RPC access is disabled by default for the GUI.

  With the proliferation of third party desktop applications that use the Bitcoin Core RPC (e.g. Specter Desktop, Sparrow and Wasabi), this PR makes them slight easier to configure. It's no longer required to find and edit `bitcoin.conf` to add `server=1` to it.

  <img width="447" alt="Schermafbeelding 2021-09-02 om 14 25 58" src="https://user-images.githubusercontent.com/10217/131844201-be3b49a8-ae88-47e6-8992-e95ee6b70f69.png">

ACKs for top commit:
  hebasto:
    ACK bd5c826a9630f41255497e0c9a0f1872b5ab78d5, tested on Linux Mint 20.2 (Qt 5.12.8):
  shaavan:
    reACK bd5c826a9630f41255497e0c9a0f1872b5ab78d5
  promag:
    Code review ACK bd5c826a9630f41255497e0c9a0f1872b5ab78d5. Just minor fixes to the .ui form since last review.

Tree-SHA512: ab377e2358826096b499013bc3a864b7b63dff9859e96041e93ff0897d2319a35e8b3adcfb8df5f83274466c83d040d4ea18c546699421425c835e6f42562ae0

4 files changed, 30 insertions, 2 deletions

diff --git a/src/qt/forms/optionsdialog.ui b/src/qt/forms/optionsdialog.ui
index 59d220636d..087d0eb527 100644
--- a/src/qt/forms/optionsdialog.ui
+++ b/src/qt/forms/optionsdialog.ui
@@ -33,7 +33,7 @@
           <string>Automatically start %1 after logging in to the system.</string>
          </property>
          <property name="text">
-          <string>&amp;Start %1 on system login</string>
+          <string>Start %1 on system &amp;login</string>
          </property>
         </widget>
        </item>
@@ -179,7 +179,7 @@
            <property name="sizeHint" stdset="0">
             <size>
              <width>40</width>
-             <height>20</height>
+             <height>40</height>
             </size>
            </property>
           </spacer>
@@ -187,6 +187,16 @@
         </layout>
        </item>
        <item>
+        <widget class="QCheckBox" name="enableServer">
+         <property name="toolTip">
+          <string extracomment="Tooltip text for Options window setting that enables the RPC server.">This allows you or a third party tool to communicate with the node through command-line and JSON-RPC commands.</string>
+         </property>
+         <property name="text">
+          <string extracomment="An Options window setting to enable the RPC server.">Enable RPC &amp;server</string>
+         </property>
+        </widget>
+       </item>
+       <item>
         <spacer name="verticalSpacer_Main">
          <property name="orientation">
           <enum>Qt::Vertical</enum>
diff --git a/src/qt/optionsdialog.cpp b/src/qt/optionsdialog.cpp
index 92644ef24b..ac50e6518f 100644
--- a/src/qt/optionsdialog.cpp
+++ b/src/qt/optionsdialog.cpp
@@ -210,6 +210,7 @@ void OptionsDialog::setModel(OptionsModel *_model)
     connect(ui->spendZeroConfChange, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
     /* Network */
     connect(ui->allowIncoming, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
+    connect(ui->enableServer, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
     connect(ui->connectSocks, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
     connect(ui->connectSocksTor, &QCheckBox::clicked, this, &OptionsDialog::showRestartWarning);
     /* Display */
@@ -246,6 +247,7 @@ void OptionsDialog::setMapper()
     mapper->addMapping(ui->mapPortUpnp, OptionsModel::MapPortUPnP);
     mapper->addMapping(ui->mapPortNatpmp, OptionsModel::MapPortNatpmp);
     mapper->addMapping(ui->allowIncoming, OptionsModel::Listen);
+    mapper->addMapping(ui->enableServer, OptionsModel::Server);
 
     mapper->addMapping(ui->connectSocks, OptionsModel::ProxyUse);
     mapper->addMapping(ui->proxyIp, OptionsModel::ProxyIP);
diff --git a/src/qt/optionsmodel.cpp b/src/qt/optionsmodel.cpp
index d87fc1f84a..9e2f38f7ec 100644
--- a/src/qt/optionsmodel.cpp
+++ b/src/qt/optionsmodel.cpp
@@ -149,6 +149,13 @@ void OptionsModel::Init(bool resetSettings)
     if (!gArgs.SoftSetBoolArg("-listen", settings.value("fListen").toBool()))
         addOverriddenOption("-listen");
 
+    if (!settings.contains("server")) {
+        settings.setValue("server", false);
+    }
+    if (!gArgs.SoftSetBoolArg("-server", settings.value("server").toBool())) {
+        addOverriddenOption("-server");
+    }
+
     if (!settings.contains("fUseProxy"))
         settings.setValue("fUseProxy", false);
     if (!settings.contains("addrProxy"))
@@ -363,6 +370,8 @@ QVariant OptionsModel::data(const QModelIndex & index, int role) const
             return settings.value("nThreadsScriptVerif");
         case Listen:
             return settings.value("fListen");
+        case Server:
+            return settings.value("server");
         default:
             return QVariant();
         }
@@ -528,6 +537,12 @@ bool OptionsModel::setData(const QModelIndex & index, const QVariant & value, in
                 setRestartRequired(true);
             }
             break;
+        case Server:
+            if (settings.value("server") != value) {
+                settings.setValue("server", value);
+                setRestartRequired(true);
+            }
+            break;
         default:
             break;
         }
diff --git a/src/qt/optionsmodel.h b/src/qt/optionsmodel.h
index 203ee27ad8..65544acfbd 100644
--- a/src/qt/optionsmodel.h
+++ b/src/qt/optionsmodel.h
@@ -69,6 +69,7 @@ public:
         ExternalSignerPath,     // QString
         SpendZeroConfChange,    // bool
         Listen,                 // bool
+        Server,                 // bool
         OptionIDRowCount,
     };