support range format in worker

docs/installation/presto-admin-configuration.rst

@@ -93,6 +93,18 @@ username and port, a sample ``config.json`` would be:
  "workers": ["slave1","slave2","slave3","slave4","slave5"]
  }
 
+You can specify a range of workers by including the number range in brackets in the worker name.  For example:
+
+::
+
+    "workers": ["worker[01-03]"]
+
+is the same as
+
+::
+
+    "workers": ["worker01", "worker02", "worker03"]
+
 
 .. _sudo-password-spec:
 

prestoadmin/standalone/config.py

@@ -15,6 +15,8 @@
 """
 Module for setting and validating the presto-admin config
 """
+import re
+
 from fabric.api import env
 from overrides import overrides
 
@@ -116,6 +118,7 @@ def validate(conf):
     except KeyError:
         pass
     else:
+        workers = [h for host in workers for h in _expand_host(host)]
         conf['workers'] = validate_workers(workers)
 
     try:
@@ -140,6 +143,26 @@ def validate_workers(workers):
     return workers
 
 
+def _expand_host(host):
+    match = re.match("(.*)\[(\d{1,})-(\d{1,})\](.*)", host)
+    if match is not None and len(match.groups()) == 4:
+        prefix, start, end, suffix = match.groups()
+        if int(start) > int(end):
+            raise ValueError("the range format must be ascending order")
+        if len(start) == len(end) and len(start) > 1:
+            number_format = "{0:0" + str(len(start)) + "d}"
+            host_list = [number_format.format(i) for i in range(int(start), int(end) + 1)]
+            return [_format_hostname(prefix, i, suffix) for i in host_list]
+        else:
+            return [_format_hostname(prefix, i, suffix) for i in range(int(start), int(end) + 1)]
+    else:
+        return [host]
+
+
+def _format_hostname(prefix, number, suffix):
+    return "{prefix}{num}{suffix}".format(prefix=prefix, num=number, suffix=suffix)
+
+
 class StandaloneConfig(BaseConfig):
     def __init__(self):
         super(StandaloneConfig, self).__init__(get_topology_path(), _TOPOLOGY_CONFIG)

tests/unit/test_expand.py

@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+#
+# 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.
+
+from prestoadmin.standalone.config import _expand_host
+from tests.unit.base_unit_case import BaseUnitCase
+
+
+class TestExpandHost(BaseUnitCase):
+
+    def test_basic_expand_host_01(self):
+        input_host = "worker0[1-2].example.com"
+        expected = ["worker01.example.com", "worker02.example.com"]
+        self.assertEqual(expected, _expand_host(input_host))
+
+    def test_basic_expand_host_02(self):
+        input_host = "worker[01-02].example.com"
+        expected = ["worker01.example.com", "worker02.example.com"]
+        self.assertEqual(expected, _expand_host(input_host))
+
+    def test_expand_host_include_hyphen(self):
+        input_host = "cdh5-[1-2].example.com"
+        expected = ["cdh5-1.example.com", "cdh5-2.example.com"]
+        self.assertEqual(expected, _expand_host(input_host))
+
+    def test_not_expand_host(self):
+        input_host = "worker1.example.com"
+        expected = ["worker1.example.com"]
+        self.assertEqual(expected, _expand_host(input_host))
+
+    def test_except_expand_host(self):
+        input_host = "worker0[3-2].example.com"
+        self.assertRaises(ValueError, _expand_host, input_host)