From b24fa931b2389421a7cf77835be75d2b226bd3f8 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Thu, 18 May 2017 12:05:13 -0400
Subject: [PATCH] mon/MgrMonitor: add 'mgr dump [epoch]' command

Signed-off-by: Sage Weil <sage@redhat.com>
---
 qa/workunits/cephtool/test.sh |  2 ++
 src/mon/MgrMonitor.cc         | 54 ++++++++++++++++++++++++++++++++++-
 src/mon/MonCommands.h         |  4 +++
 3 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/qa/workunits/cephtool/test.sh b/qa/workunits/cephtool/test.sh
index 92a8db1f3c54f..07b8df941cb70 100755
--- a/qa/workunits/cephtool/test.sh
+++ b/qa/workunits/cephtool/test.sh
@@ -680,6 +680,8 @@ function test_mon_misc()
   ceph log "$mymsg"
   ceph_watch_wait "$mymsg"
 
+  ceph mgr dump
+
   ceph mon metadata a
   ceph mon metadata
   ceph node ls
diff --git a/src/mon/MgrMonitor.cc b/src/mon/MgrMonitor.cc
index b36da2fce57c4..0eda70d994dbc 100644
--- a/src/mon/MgrMonitor.cc
+++ b/src/mon/MgrMonitor.cc
@@ -444,8 +444,60 @@ void MgrMonitor::drop_standby(uint64_t gid)
 
 bool MgrMonitor::preprocess_command(MonOpRequestRef op)
 {
-  return false;
+  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  std::stringstream ss;
+  bufferlist rdata;
+
+  std::map<std::string, cmd_vartype> cmdmap;
+  if (!cmdmap_from_json(m->cmd, &cmdmap, ss)) {
+    string rs = ss.str();
+    mon->reply_command(op, -EINVAL, rs, rdata, get_last_committed());
+    return true;
+  }
+
+  MonSession *session = m->get_session();
+  if (!session) {
+    mon->reply_command(op, -EACCES, "access denied", rdata,
+		       get_last_committed());
+    return true;
+  }
 
+  string format;
+  cmd_getval(g_ceph_context, cmdmap, "format", format, string("json-pretty"));
+  boost::scoped_ptr<Formatter> f(Formatter::create(format));
+
+  string prefix;
+  cmd_getval(g_ceph_context, cmdmap, "prefix", prefix);
+  int r = 0;
+
+  if (prefix == "mgr dump") {
+    int64_t epoch = 0;
+    cmd_getval(g_ceph_context, cmdmap, "epoch", epoch, (int64_t)map.get_epoch());
+    if (epoch == (int64_t)map.get_epoch()) {
+      f->dump_object("mgrmap", map);
+    } else {
+      bufferlist bl;
+      int err = get_version(epoch, bl);
+      if (err == -ENOENT) {
+	r = -ENOENT;
+	ss << "there is no map for epoch " << epoch;
+	goto reply;
+      }
+      MgrMap m;
+      auto p = bl.begin();
+      m.decode(p);
+      f->dump_object("mgrmap", m);
+    }
+    f->flush(rdata);
+  } else {
+    return false;
+  }
+
+reply:
+  string rs;
+  getline(ss, rs);
+  mon->reply_command(op, r, rs, rdata, get_last_committed());
+  return true;
 }
 
 bool MgrMonitor::prepare_command(MonOpRequestRef op)
diff --git a/src/mon/MonCommands.h b/src/mon/MonCommands.h
index c7b932690b91e..2c91d79c5d4ca 100644
--- a/src/mon/MonCommands.h
+++ b/src/mon/MonCommands.h
@@ -840,5 +840,9 @@ COMMAND("config-key dump", "dump keys and values", "config-key", "r", "cli,rest"
 /*
  * mon/MgrMonitor.cc
  */
+COMMAND("mgr dump "				     \
+	"name=epoch,type=CephInt,range=0,req=false", \
+	"dump the latest MgrMap",		     \
+	"mgr", "rw", "cli,rest")
 COMMAND("mgr fail name=who,type=CephString", \
 	"treat the named manager daemon as failed", "mgr", "rw", "cli,rest")
-- 
2.39.5