changing of the volume types after volume is created.

with this patch, one can do all the below operations:

on a simple distribute volume 'test' with bricks A,B, add bricks C and D:

 bash# gluster volume add-brick test replica 2 C D

now the volume 'test' becomes distribute-replicate, with pairs A-C, B-D.
same holds good for stripe.

and now, one can change the replica count 2 on volume 'test' to 4 like below:

 bash# gluster volume add-brick test replica 4 E F G H

now, volume has 'replica' count 4, with pairs being 'A-C-E-F' and 'B-D-G-H'.

after this, if user wants to reduce the replica count, he can do

 bash# gluster volume remove-brick test replica 3 C H # (one from each pair)

This should work to reduce the replica count

Change-Id: I4f109141a9ba7be4a92a5f5810a4163baeb92973
BUG: 3305
Reviewed-on: http://review.gluster.com/158
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vijay@gluster.com>

2 files changed, 86 insertions, 9 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index e09db1ce6..eaeb3f1ae 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -726,6 +726,11 @@ cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
         int     ret = -1;
         int     brick_count = 0, brick_index = 0;
         char    *bricks = NULL;
+        char    *opwords_cl[] = { "replica", "stripe", NULL };
+        gf1_cluster_type type = GF_CLUSTER_TYPE_NONE;
+        int     count = 1;
+        char    *w = NULL;
+        int     index;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
@@ -751,8 +756,58 @@ cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
                 ret = -1;
                 goto out;
         }
+        if (wordcount < 6) {
+                /* seems no options are given, go directly to the parse_brick */
+                brick_index = 3;
+                type = GF_CLUSTER_TYPE_NONE;
+                goto parse_bricks;
+        }
 
-        brick_index = 3;
+        w = str_getunamb (words[3], opwords_cl);
+        if (!w) {
+                type = GF_CLUSTER_TYPE_NONE;
+                index = 3;
+        } else if ((strcmp (w, "replica")) == 0) {
+                type = GF_CLUSTER_TYPE_REPLICATE;
+                if (wordcount < 5) {
+                        ret = -1;
+                        goto out;
+                }
+                count = strtol (words[4], NULL, 0);
+                if (!count || (count < 2)) {
+                        cli_out ("replica count should be greater than 1");
+                        ret = -1;
+                        goto out;
+                }
+                ret = dict_set_int32 (dict, "replica-count", count);
+                if (ret)
+                        goto out;
+                index = 5;
+        } else if ((strcmp (w, "stripe")) == 0) {
+                type = GF_CLUSTER_TYPE_STRIPE;
+                if (wordcount < 5) {
+                        ret = -1;
+                        goto out;
+                }
+                count = strtol (words[4], NULL, 0);
+                if (!count || (count < 2)) {
+                        cli_out ("stripe count should be greater than 1");
+                        ret = -1;
+                        goto out;
+                }
+                ret = dict_set_int32 (dict, "stripe-count", count);
+                if (ret)
+                        goto out;
+                index = 5;
+        } else {
+                GF_ASSERT (!"opword mismatch");
+                ret = -1;
+                goto out;
+        }
+
+        brick_index = index;
+
+parse_bricks:
         ret = cli_cmd_bricks_parse (words, wordcount, brick_index, &bricks,
                                     &brick_count);
         if (ret)
@@ -794,20 +849,21 @@ cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
         int32_t j = 0;
         char    *tmp_brick = NULL;
         char    *tmp_brick1 = NULL;
+        char    *type_opword[] = { "replica", NULL };
         char    *opwords[] = { "start", "commit", "pause", "abort", "status",
                                "force", NULL };
         char    *w = NULL;
         int32_t  command = GF_OP_CMD_NONE;
+        long     count = 0;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
 
-        dict = dict_new ();
-
-        if (!dict)
+        if (wordcount < 4)
                 goto out;
 
-        if (wordcount < 3)
+        dict = dict_new ();
+        if (!dict)
                 goto out;
 
         volname = (char *)words[2];
@@ -818,6 +874,29 @@ cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
         if (ret)
                 goto out;
 
+        brick_index = 3;
+        w = str_getunamb (words[3], type_opword);
+        if (w && !strcmp ("replica", w)) {
+                if (wordcount < 5) {
+                        ret = -1;
+                        goto out;
+                }
+                count = strtol (words[4], NULL, 0);
+                if (count < 1) {
+                        cli_out ("replica count should be greater than 0 in "
+                                 "case of remove-brick");
+                        ret = -1;
+                        goto out;
+                }
+
+                ret = dict_set_int32 (dict, "replica-count", count);
+                if (ret)
+                        goto out;
+                brick_index = 5;
+        } else if (w) {
+                GF_ASSERT (!"opword mismatch");
+        }
+
         w = str_getunamb (words[wordcount - 1], opwords);
         if (!w) {
                 /* Should be default 'force' */
@@ -861,8 +940,6 @@ cli_cmd_volume_remove_brick_parse (const char **words, int wordcount,
                         command);
 
 
-        brick_index = 3;
-
         tmp_index = brick_index;
         tmp_brick = GF_MALLOC(2048 * sizeof(*tmp_brick), gf_common_mt_char);
 
diff --git a/cli/src/cli-cmd-volume.c b/cli/src/cli-cmd-volume.c
index 425840f7f..36e4c659c 100644
--- a/cli/src/cli-cmd-volume.c
+++ b/cli/src/cli-cmd-volume.c
@@ -1601,11 +1601,11 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_volume_rename_cbk,
           "rename volume <VOLNAME> to <NEW-VOLNAME>"},*/
 
-        { "volume add-brick <VOLNAME> <NEW-BRICK> ...",
+        { "volume add-brick <VOLNAME> [<stripe|replica> <COUNT>] <NEW-BRICK> ...",
           cli_cmd_volume_add_brick_cbk,
           "add brick to volume <VOLNAME>"},
 
-        { "volume remove-brick <VOLNAME> <BRICK> ... {start|pause|abort|status|commit|force}",
+        { "volume remove-brick <VOLNAME> [replica <COUNT>] <BRICK> ... {start|pause|abort|status|commit|force}",
           cli_cmd_volume_remove_brick_cbk,
           "remove brick from volume <VOLNAME>"},