Added preliminary testing of WAL monitor

monitor/src/main/scala/com/outr/arango/monitor/ArangoDBMonitor.scala

@@ -0,0 +1,43 @@
+package com.outr.arango.monitor
+
+import cats.effect.{ExitCode, IO, IOApp}
+import com.outr.arango.Graph
+import com.outr.arango.core.ArangoDBConfig
+import fabric.Json
+import fabric.io.JsonFormatter
+import spice.http.client.HttpClient
+import spice.net._
+
+// TODO: Work in progress
+case class ArangoDBMonitor(config: ArangoDBConfig = ArangoDBConfig()) {
+  private lazy val client = HttpClient
+    .url(URL(
+      protocol = if (config.ssl) Protocol.Https else Protocol.Http,
+      host = config.hosts.head.host,
+      port = config.hosts.head.port
+    ))
+  // http://localhost:8529/_api/wal/tail?from=188771
+  // TODO: Handle user authentication
+  def tail(db: Option[String] = None,
+           from: Option[Int] = None,
+           to: Option[Int] = None,
+           syncerId: Option[String] = None): IO[Unit] = {
+    val path = db match {
+      case Some(dbName) => s"/_db/$dbName/_api/wal/tail"
+      case None => "/_api/wal/tail"
+    }
+    client
+      .path(URLPath.parse(path))
+      .call[Json]
+      .map { json =>
+        scribe.info(s"Tail: ${JsonFormatter.Default(json)}")
+      }
+  }
+}
+
+object ArangoDBMonitor extends IOApp {
+  override def run(args: List[String]): IO[ExitCode] = {
+    val monitor = ArangoDBMonitor()
+    monitor.tail().map(_ => ExitCode.Success)
+  }
+}