cli: Add warning message while converting to replica 2 configuration

Currently while creating replica 2 volume we display a warning message
of ending up in split-brain. But while converting an existing volume
from other configuration to replica 2 by add-brick or remove-brick
operations we do not show any such messages.
With this fix in add-brick and remove-brick cases also we will display
the same warning message and prompt for confirmation if the configuration
changes to replica 2.

Change-Id: Ifc4ed6994a087d2403894f4e743c4eb41633276b
fixes: bz#1627044
Signed-off-by: karthik-us <ksubrahm@redhat.com>

3 files changed, 59 insertions, 15 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index 9ec4d312e6f..48d6ebd64a7 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -1709,8 +1709,8 @@ out:
 }
 
 int32_t
-cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
-                                dict_t **options, int *ret_type)
+cli_cmd_volume_add_brick_parse (struct cli_state *state, const char **words,
+                                int wordcount, dict_t **options, int *ret_type)
 {
         dict_t  *dict = NULL;
         char    *volname = NULL;
@@ -1725,6 +1725,8 @@ cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
         int     index;
         gf_boolean_t is_force = _gf_false;
         int wc = wordcount;
+        gf_answer_t answer = GF_ANSWER_NO;
+        const char *question = NULL;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
@@ -1789,6 +1791,24 @@ cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
                                 goto out;
                         index = 7;
                 }
+
+                if (count == 2) {
+                        if (strcmp (words[wordcount - 1], "force")) {
+                                question = "Replica 2 volumes are prone to "
+                                           "split-brain. Use Arbiter or "
+                                           "Replica 3 to avaoid this. See: "
+                                           "http://docs.gluster.org/en/latest/Administrator%20Guide/Split%20brain%20and%20ways%20to%20deal%20with%20it/."
+                                           "\nDo you still want to continue?\n";
+                                answer = cli_cmd_get_confirmation (state,
+                                                                   question);
+                                if (GF_ANSWER_NO == answer) {
+                                        gf_log ("cli", GF_LOG_ERROR, "Add brick"
+                                                " cancelled, exiting");
+                                        ret = -1;
+                                        goto out;
+                                }
+                        }
+                }
         } else if ((strcmp (w, "stripe")) == 0) {
                 type = GF_CLUSTER_TYPE_STRIPE;
                 count = strtol (words[4], NULL, 0);
@@ -1992,9 +2012,10 @@ out:
 }
 
 int32_t
-cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
-                                   dict_t **options, int *question,
-                                   int *brick_count, int32_t *comm)
+cli_cmd_volume_remove_brick_parse (struct cli_state *state, const char **words,
+                                   int wordcount, dict_t **options,
+                                   int *question, int *brick_count,
+                                   int32_t *comm)
 {
         dict_t  *dict = NULL;
         char    *volname = NULL;
@@ -2012,6 +2033,8 @@ cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
         char    *w = NULL;
         int32_t  command = GF_OP_CMD_NONE;
         long     count = 0;
+        gf_answer_t answer = GF_ANSWER_NO;
+        const char *ques = NULL;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
@@ -2046,6 +2069,24 @@ cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
                         goto out;
                 }
 
+                if (count == 2) {
+                        if (strcmp (words[wordcount - 1], "force")) {
+                                ques = "Replica 2 volumes are prone to "
+                                       "split-brain. Use Arbiter or Replica 3 "
+                                       "to avaoid this. See: "
+                                       "http://docs.gluster.org/en/latest/Administrator%20Guide/Split%20brain%20and%20ways%20to%20deal%20with%20it/."
+                                       "\nDo you still want to continue?\n";
+                                answer = cli_cmd_get_confirmation (state,
+                                                                   ques);
+                                if (GF_ANSWER_NO == answer) {
+                                        gf_log ("cli", GF_LOG_ERROR, "Remove "
+                                                "brick cancelled, exiting");
+                                        ret = -1;
+                                        goto out;
+                                }
+                        }
+                }
+
                 ret = dict_set_int32 (dict, "replica-count", count);
                 if (ret)
                         goto out;
diff --git a/cli/src/cli-cmd-volume.c b/cli/src/cli-cmd-volume.c
index d8b9e25f198..3d075a326bf 100644
--- a/cli/src/cli-cmd-volume.c
+++ b/cli/src/cli-cmd-volume.c
@@ -1023,7 +1023,8 @@ cli_cmd_volume_add_brick_cbk (struct cli_state *state,
         if (!frame)
                 goto out;
 
-        ret = cli_cmd_volume_add_brick_parse (words, wordcount, &options, 0);
+        ret = cli_cmd_volume_add_brick_parse (state, words, wordcount, &options,
+                                              0);
         if (ret) {
                 cli_usage_out (word->pattern);
                 parse_error = 1;
@@ -1155,7 +1156,8 @@ do_cli_cmd_volume_attach_tier (struct cli_state *state,
         if (!frame)
                 goto out;
 
-        ret = cli_cmd_volume_add_brick_parse (words, wordcount, &options, &type);
+        ret = cli_cmd_volume_add_brick_parse (state, words, wordcount, &options,
+                                              &type);
         if (ret) {
                 cli_usage_out (word->pattern);
                 parse_error = 1;
@@ -2032,9 +2034,9 @@ cli_cmd_volume_remove_brick_cbk (struct cli_state *state,
         if (!frame)
                 goto out;
 
-        ret = cli_cmd_volume_remove_brick_parse (words, wordcount, &options,
-                                                 &need_question, &brick_count,
-                                                 &command);
+        ret = cli_cmd_volume_remove_brick_parse (state, words, wordcount,
+                                                 &options, &need_question,
+                                                 &brick_count, &command);
         if (ret) {
                 cli_usage_out (word->pattern);
                 parse_error = 1;
diff --git a/cli/src/cli.h b/cli/src/cli.h
index 3421d6911fb..9a392e4ec1d 100644
--- a/cli/src/cli.h
+++ b/cli/src/cli.h
@@ -261,8 +261,8 @@ cli_cmd_get_state_parse (struct cli_state *state, const char **words,
                          int wordcount, dict_t **options, char **op_errstr);
 
 int32_t
-cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
-                                dict_t **options, int *type);
+cli_cmd_volume_add_brick_parse (struct cli_state *state, const char **words,
+                                int wordcount, dict_t **options, int *type);
 
 int32_t
 cli_cmd_volume_detach_tier_parse (const char **words, int wordcount,
@@ -277,9 +277,10 @@ cli_cmd_volume_old_tier_parse (const char **words, int wordcount,
                            dict_t **options);
 
 int32_t
-cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
-                                   dict_t **options, int *question,
-                                   int *brick_count, int32_t *command);
+cli_cmd_volume_remove_brick_parse (struct cli_state *state, const char **words,
+                                   int wordcount, dict_t **options,
+                                   int *question, int *brick_count,
+                                   int32_t *command);
 
 int32_t
 cli_cmd_volume_replace_brick_parse (const char **words, int wordcount,