region_sharding: working resharding example

Signed-off-by: deepthi <deepthi@planetscale.com>

.github/workflows/region_example.yml

@@ -51,5 +51,5 @@ jobs:
         fi
         # Make sure that testing is entirely non-reliant on config
         mv config config-moved
-        sed -i 's/user\/my-vitess/runner\/work\/vitess\/vitess/g' examples/region_sharding/main_vschema.json #set correct path to countries.json
+        sed -i 's/user\/my-vitess/runner\/work\/vitess\/vitess/g' examples/region_sharding/main_vschema_sharded.json #set correct path to countries.json
         eatmydata -- test/region_example.sh

examples/region_sharding/101_initial_cluster.sh

@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-# this script brings up zookeeper and all the vitess components
+# this script brings up topo server and all the vitess components
 # required for a single shard deployment.
 
 source ./env.sh
@@ -31,27 +31,17 @@ fi
 # start vtctld
 CELL=zone1 ./scripts/vtctld-up.sh
 
-# start vttablets for main keyspace. we start only one tablet each (master)
+# start unsharded keyspace and tablet
 CELL=zone1 TABLET_UID=100 ./scripts/mysqlctl-up.sh
-SHARD=-40 CELL=zone1 KEYSPACE=main TABLET_UID=100 ./scripts/vttablet-up.sh
-CELL=zone1 TABLET_UID=200 ./scripts/mysqlctl-up.sh
-SHARD=40-80 CELL=zone1 KEYSPACE=main TABLET_UID=200 ./scripts/vttablet-up.sh
-CELL=zone1 TABLET_UID=300 ./scripts/mysqlctl-up.sh
-SHARD=80-c0 CELL=zone1 KEYSPACE=main TABLET_UID=300 ./scripts/vttablet-up.sh
-CELL=zone1 TABLET_UID=400 ./scripts/mysqlctl-up.sh
-SHARD=c0- CELL=zone1 KEYSPACE=main TABLET_UID=400 ./scripts/vttablet-up.sh
+SHARD=0 CELL=zone1 KEYSPACE=main TABLET_UID=100 ./scripts/vttablet-up.sh
 
-# set master
-vtctlclient InitShardMaster -force main/-40 zone1-100
-vtctlclient InitShardMaster -force main/40-80 zone1-200
-vtctlclient InitShardMaster -force main/80-c0 zone1-300
-vtctlclient InitShardMaster -force main/c0- zone1-400
+vtctlclient InitShardMaster -force main/0 zone1-100
 
 # create the schema
 vtctlclient ApplySchema -sql-file create_main_schema.sql main
 
 # create the vschema
-vtctlclient ApplyVSchema -vschema_file main_vschema.json main
+vtctlclient ApplyVSchema -vschema_file main_vschema_initial.json main
 
 # start vtgate
 CELL=zone1 ./scripts/vtgate-up.sh

examples/region_sharding/201_main_sharded.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# Copyright 2020 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+source ./env.sh
+
+# apply sharding vschema
+vtctlclient ApplyVSchema -vschema_file main_vschema_sharded.json main
+
+# create the schema needed for lookup vindex
+vtctlclient ApplySchema -sql-file create_lookup_schema.sql main
+
+# create the lookup vindex
+vtctlclient CreateLookupVindex -tablet_types=MASTER main "$(cat lookup_vindex.json)"
+
+# we have to wait for replication to catch up
+# Can see on vttablet status page Vreplication that copy is complete
+sleep 5
+
+#externalize vindex
+vtctlclient ExternalizeVindex main.customer_region_lookup

examples/region_sharding/202_new_tablets.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# Copyright 2020 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+source ./env.sh
+
+# start vttablets for new shards. we start only one tablet each (master)
+CELL=zone1 TABLET_UID=200 ./scripts/mysqlctl-up.sh
+SHARD=-40 CELL=zone1 KEYSPACE=main TABLET_UID=200 ./scripts/vttablet-up.sh
+CELL=zone1 TABLET_UID=300 ./scripts/mysqlctl-up.sh
+SHARD=40-80 CELL=zone1 KEYSPACE=main TABLET_UID=300 ./scripts/vttablet-up.sh
+CELL=zone1 TABLET_UID=400 ./scripts/mysqlctl-up.sh
+SHARD=80-c0 CELL=zone1 KEYSPACE=main TABLET_UID=400 ./scripts/vttablet-up.sh
+CELL=zone1 TABLET_UID=500 ./scripts/mysqlctl-up.sh
+SHARD=c0- CELL=zone1 KEYSPACE=main TABLET_UID=500 ./scripts/vttablet-up.sh
+
+# set master
+vtctlclient InitShardMaster -force main/-40 zone1-200
+vtctlclient InitShardMaster -force main/40-80 zone1-300
+vtctlclient InitShardMaster -force main/80-c0 zone1-400
+vtctlclient InitShardMaster -force main/c0- zone1-500

examples/region_sharding/203_reshard.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+# Copyright 2020 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+source ./env.sh
+
+vtctlclient Reshard -tablet_types=MASTER main.main2regions '0' '-40,40-80,80-c0,c0-'

examples/region_sharding/204_switch_reads.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+
+# Copyright 2020 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# this script migrates traffic for the rdonly and replica tablets
+
+source ./env.sh
+
+vtctlclient SwitchReads -tablet_type=rdonly main.main2regions
+vtctlclient SwitchReads -tablet_type=replica main.main2regions

examples/region_sharding/205_switch_writes.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+
+# Copyright 2020 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# this script migrates traffic for the master tablet
+
+source ./env.sh
+
+vtctlclient SwitchWrites main.main2regions
+
+# to go back to unsharded
+# call SwitchReads and SwitchWrites with workflow main.main2regions_reverse
+# delete vreplication rows from sharded tablets
+# drop all the tables
+# change vschema back to unsharded
+# drop lookup table
+

examples/region_sharding/206_down_shard_0.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+# Copyright 2019 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# this script brings down the tablets for main/0 keyspace/shard
+
+source ./env.sh
+
+CELL=zone1 TABLET_UID=100 ./scripts/vttablet-down.sh
+CELL=zone1 TABLET_UID=100 ./scripts/mysqlctl-down.sh

examples/region_sharding/207_delete_shard_0.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+# Copyright 2019 The Vitess Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# this script deletes the old shard 0 which has been replaced by 4 shards
+
+source ./env.sh
+
+vtctlclient DeleteShard -recursive main/0

examples/region_sharding/301_teardown.sh

@@ -21,7 +21,7 @@ source ./env.sh
 
 ./scripts/vtgate-down.sh
 
-for tablet in 100 200 300 400; do
+for tablet in 200 300 400 500; do
 	if vtctlclient -server localhost:15999 GetTablet zone1-$tablet >/dev/null 2>&1; then
 		echo "Shutting down tablet zone1-$tablet"
 		CELL=zone1 TABLET_UID=$tablet ./scripts/vttablet-down.sh
@@ -45,7 +45,7 @@ fi
 if [ ! -z "$VTDATAROOT" ]; then
 
 	if pgrep -f -l "$VTDATAROOT" >/dev/null; then
-		echo "ERROR: Stale processes detected! It is recommended to manuallly kill them:"
+		echo "ERROR: Stale processes detected! It is recommended to manually kill them:"
 		pgrep -f -l "$VTDATAROOT"
 	else
 		echo "All good! It looks like every process has shut down"

examples/region_sharding/README.md

@@ -10,13 +10,45 @@ This document contains the summary of the commands to be run.
 	    "region_map": "/home/user/vitess/examples/region_sharding/countries.json",
 
 
-# Bring up initial cluster and main keyspace
+# Bring up initial cluster and main keyspace (unsharded)
 ./101_initial_cluster.sh
 
+# setup aliases
+alias mysql="command mysql -h 127.0.0.1 -P 15306"
+alias vtctlclient="command vtctlclient -server localhost:15999 -log_dir ${VTDATAROOT}/tmp -alsologtostderr"
+
 # Insert and verify data
 mysql < insert_customers.sql
+mysql --table < show_initial_data.sql
+
+# create schema and vschema for sharding (+lookup vindex)
+./201_main_sharded.sh
+
+# bring up shards and tablets
+./202_new_tablets.sh
+
+# reshard
+./203_reshard.sh
+
+# SwitchReads
+./204_switch_reads.sh
+
+# run script to create traffic before switching writes
+#./client.sh
+
+# SwitchWrites
+./205_switch_writes.sh
+# show no / minimal write errors during switch
+
+# verify sharded data
 mysql --table < show_data.sql
 
+# down shard
+./206_down_shard_0.sh
+
+# delete shard 0
+./207_delete_shard_0.sh
+
 # Down cluster
-./201_teardown.sh
+./301_teardown.sh
 ```

examples/region_sharding/create_lookup_schema.sql

@@ -0,0 +1,5 @@
+CREATE TABLE customer_lookup (
+  id int NOT NULL,
+  keyspace_id varbinary(256),
+  primary key(id)
+  );

examples/region_sharding/create_main_schema.sql

@@ -5,8 +5,3 @@ CREATE TABLE customer (
   country varbinary(256),
   primary key(id)
   );
-CREATE TABLE customer_lookup (
-  id int NOT NULL,
-  keyspace_id varbinary(256),
-  primary key(id)
-  );

examples/region_sharding/lookup_vindex.json

@@ -0,0 +1,24 @@
+{
+  "sharded": true,
+  "vindexes": {
+    "customer_region_lookup": {
+      "type": "consistent_lookup_unique",
+      "params": {
+        "table": "main.customer_lookup",
+        "from": "id",
+        "to": "keyspace_id"
+      },
+      "owner": "customer"
+    }
+  },
+  "tables": {
+    "customer": {
+      "column_vindexes": [
+        {
+          "column": "id",
+          "name": "customer_region_lookup"
+        }
+      ]
+    }
+  }
+}

examples/region_sharding/main_vschema.json

@@ -1,46 +0,0 @@
-{
-  "sharded": true,
-  "vindexes": {
-    "region_vdx": {
-	"type": "region_json",
-	"params": {
-	    "region_map": "/home/user/my-vitess/examples/region_sharding/countries.json",
-	    "region_bytes": "1"
-	}
-    },
-    "customer_region_lookup": {
-        "type": "consistent_lookup_unique",
-        "params": {
-            "table": "customer_lookup",
-            "from": "id",
-            "to": "keyspace_id"
-        },
-        "owner": "customer"
-    },
-      "identity": {
-	  "type": "binary"
-      }
-  },
-  "tables": {
-    "customer_lookup": {
-      "column_vindexes": [
-	{
-            "column": "keyspace_id",
-            "name": "identity"
-        }
-      ]
-    },
-    "customer": {
-      "column_vindexes": [
-        {
-            "columns": ["id", "country"],
-	    "name": "region_vdx"
-        },
-	{
-            "column": "id",
-            "name": "customer_region_lookup"
-        }
-      ]
-    }
-  }
-}

examples/region_sharding/main_vschema_initial.json

@@ -0,0 +1,5 @@
+{
+  "tables": {
+    "customer": {}
+  }
+}

examples/region_sharding/main_vschema_sharded.json

@@ -0,0 +1,22 @@
+{
+  "sharded": true,
+  "vindexes": {
+    "region_vdx": {
+      "type": "region_json",
+      "params": {
+        "region_map": "/home/user/my-vitess/examples/region_sharding/countries.json",
+        "region_bytes": "1"
+      }
+    }
+  },
+  "tables": {
+    "customer": {
+      "column_vindexes": [
+        {
+          "columns": ["id", "country"],
+	      "name": "region_vdx"
+        }
+      ]
+    }
+  }
+}

examples/region_sharding/show_initial_data.sql

@@ -0,0 +1,2 @@
+use main;
+select * from customer;

test/region_example.sh

@@ -32,6 +32,28 @@ source ./env.sh # Required so that "mysql" works from alias
 sleep 5 # Give vtgate time to really start.
 
 mysql < insert_customers.sql
-mysql --table < show_data.sql
+mysql --table < show_initial_data.sql
 
-./201_teardown.sh
+# create schema and vschema for sharding (+lookup vindex)
+./201_main_sharded.sh
+
+# bring up shards and tablets
+./202_new_tablets.sh
+
+# reshard
+./203_reshard.sh
+
+# SwitchReads
+./204_switch_reads.sh
+
+# SwitchWrites
+./205_switch_writes.sh
+
+# down shard
+./206_down_shard_0.sh
+
+# delete shard 0
+./207_delete_shard_0.sh
+
+# Down cluster
+./301_teardown.sh