Raft Notary: bootstrap command line flag

docs/source/running-a-notary.rst

@@ -28,3 +28,6 @@ For ``ValidatingNotaryService``, it is:
 
 Setting up a Raft notary is currently slightly more involved and is not recommended for prototyping purposes. There is
 work in progress to simplify it. To see it in action, however, you can try out the :ref:`notary-demo`.
+
+Use the `--bootstrap-raft-cluster` command line argument when starting the first node of a notary cluster for the first
+time. When the flag is set, the node will act as a seed for the cluster that other members can join.

node/src/main/kotlin/net/corda/node/ArgsParser.kt

@@ -36,6 +36,7 @@ class ArgsParser {
     private val isVersionArg = optionParser.accepts("version", "Print the version and exit")
     private val justGenerateNodeInfoArg = optionParser.accepts("just-generate-node-info",
             "Perform the node start-up task necessary to generate its nodeInfo, save it to disk, then quit")
+    private val bootstrapRaftClusterArg = optionParser.accepts("bootstrap-raft-cluster", "Bootstraps Raft cluster. The node forms a single node cluster (ignoring otherwise configured peer addresses), acting as a seed for other nodes to join the cluster.")
     private val helpArg = optionParser.accepts("help").forHelp()
 
     fun parse(vararg args: String): CmdLineOptions {
@@ -53,8 +54,9 @@ class ArgsParser {
         val noLocalShell = optionSet.has(noLocalShellArg)
         val sshdServer = optionSet.has(sshdServerArg)
         val justGenerateNodeInfo = optionSet.has(justGenerateNodeInfoArg)
+        val bootstrapRaftCluster = optionSet.has(bootstrapRaftClusterArg)
         return CmdLineOptions(baseDirectory, configFile, help, loggingLevel, logToConsole, isRegistration, isVersion,
-                noLocalShell, sshdServer, justGenerateNodeInfo)
+                noLocalShell, sshdServer, justGenerateNodeInfo, bootstrapRaftCluster)
     }
 
     fun printHelp(sink: PrintStream) = optionParser.printHelpOn(sink)
@@ -69,7 +71,8 @@ data class CmdLineOptions(val baseDirectory: Path,
                           val isVersion: Boolean,
                           val noLocalShell: Boolean,
                           val sshdServer: Boolean,
-                          val justGenerateNodeInfo: Boolean) {
+                          val justGenerateNodeInfo: Boolean,
+                          val bootstrapRaftCluster: Boolean) {
     fun loadConfig(): NodeConfiguration {
         val config = ConfigHelper.loadConfig(baseDirectory, configFile).parseAsNodeConfiguration()
         if (isRegistration) {

node/src/main/kotlin/net/corda/node/internal/NodeStartup.kt

@@ -8,6 +8,7 @@ import net.corda.core.internal.concurrent.thenMatch
 import net.corda.core.utilities.loggerFor
 import net.corda.node.*
 import net.corda.node.services.config.NodeConfiguration
+import net.corda.node.services.config.NodeConfigurationImpl
 import net.corda.node.services.transactions.bftSMaRtSerialFilter
 import net.corda.node.shell.InteractiveShell
 import net.corda.node.utilities.registration.HTTPNetworkRegistrationService
@@ -62,7 +63,21 @@ open class NodeStartup(val args: Array<String>) {
 
         drawBanner(versionInfo)
         Node.printBasicNodeInfo(LOGS_CAN_BE_FOUND_IN_STRING, System.getProperty("log-path"))
-        val conf = loadConfigFile(cmdlineOptions)
+        val conf0 = loadConfigFile(cmdlineOptions)
+
+        val conf = if (cmdlineOptions.bootstrapRaftCluster) {
+            if (conf0 is NodeConfigurationImpl) {
+                println("Bootstrapping raft cluster (starting up as seed node).")
+                // Ignore the configured clusterAddresses to make the node bootstrap a cluster instead of joining.
+                conf0.copy(notary = conf0.notary?.copy(raft = conf0.notary?.raft?.copy(clusterAddresses = emptyList())))
+            } else {
+                println("bootstrap-raft-notaries flag not recognized, exiting...")
+                exitProcess(1)
+            }
+        } else {
+            conf0
+        }
+
         banJavaSerialisation(conf)
         preNetworkRegistration(conf)
         maybeRegisterWithNetworkAndExit(cmdlineOptions, conf)

node/src/test/kotlin/net/corda/node/ArgsParserTest.kt

@@ -24,7 +24,8 @@ class ArgsParserTest {
                 isVersion = false,
                 noLocalShell = false,
                 sshdServer = false,
-                justGenerateNodeInfo = false))
+                justGenerateNodeInfo = false,
+                bootstrapRaftCluster = false))
     }
 
     @Test
@@ -124,4 +125,10 @@ class ArgsParserTest {
         val cmdLineOptions = parser.parse("--just-generate-node-info")
         assertThat(cmdLineOptions.justGenerateNodeInfo).isTrue()
     }
+
+    @Test
+    fun `bootstrap raft cluster`() {
+        val cmdLineOptions = parser.parse("--bootstrap-raft-cluster")
+        assertThat(cmdLineOptions.bootstrapRaftCluster).isTrue()
+    }
 }