Disable interpolation for config file

With this commit we disable interpolation in Rally's configuration file.
It causes trouble with certain characters in passwords and was only used
sparingly anyway.

Closes #519
Relates #524

esrally/config.py

@@ -38,8 +38,8 @@ def present(self):
         """
         return os.path.isfile(self.location)
 
-    def load(self, interpolation=configparser.ExtendedInterpolation()):
-        config = configparser.ConfigParser(interpolation=interpolation)
+    def load(self):
+        config = configparser.ConfigParser()
         config.read(self.location, encoding="utf-8")
         return config
 
@@ -370,7 +370,7 @@ def create_config(self, config_file, advanced_config=False, assume_defaults=Fals
         config["source"]["elasticsearch.src.subdir"] = io.basename(source_dir)
 
         config["benchmarks"] = {}
-        config["benchmarks"]["local.dataset.cache"] = "${node:root.dir}/data"
+        config["benchmarks"]["local.dataset.cache"] = os.path.join(root_dir, "data")
 
         config["reporting"] = {}
         config["reporting"]["datastore.type"] = data_store_type
@@ -515,7 +515,7 @@ def migrate(config_file, current_version, target_version, out=print, i=input):
                           % (target_version, current_version))
     # but first a backup...
     config_file.backup()
-    config = config_file.load(interpolation=None)
+    config = config_file.load()
 
     if current_version == 12 and target_version > current_version:
         # the current configuration allows to benchmark from sources
@@ -633,6 +633,10 @@ def warn_if_plugin_build_task_is_in_use(config):
 
     if current_version == 16 and target_version > current_version:
         config.pop("runtime", None)
+        if "benchmarks" in config and "local.dataset.cache" in config["benchmarks"]:
+            if config["benchmarks"]["local.dataset.cache"] == "${node:root.dir}/data":
+                root_dir = config["node"]["root.dir"]
+                config["benchmarks"]["local.dataset.cache"] = os.path.join(root_dir, "data")
         current_version = 17
         config["meta"]["config.version"] = str(current_version)
 

tests/config_test.py

@@ -252,22 +252,24 @@ def test_create_simple_config(self, guess_install_location, working_copy):
             for k, v in config_store.config[section].items():
                 print("%s::%s: %s" % (section, k, v))
 
+        root_dir = io.normalize_path(os.path.abspath("./in-memory/benchmarks"))
         self.assertTrue("meta" in config_store.config)
         self.assertEqual(str(config.Config.CURRENT_CONFIG_VERSION), config_store.config["meta"]["config.version"])
 
         self.assertTrue("system" in config_store.config)
         self.assertEqual("local", config_store.config["system"]["env.name"])
 
         self.assertTrue("node" in config_store.config)
-        self.assertEqual(io.normalize_path(os.path.abspath("./in-memory/benchmarks")), config_store.config["node"]["root.dir"])
-        self.assertEqual(io.normalize_path(os.path.abspath("./in-memory/benchmarks/src")), config_store.config["node"]["src.root.dir"])
+
+        self.assertEqual(root_dir, config_store.config["node"]["root.dir"])
+        self.assertEqual(os.path.join(root_dir, "src"), config_store.config["node"]["src.root.dir"])
 
         self.assertTrue("source" in config_store.config)
         self.assertEqual("https://github.com/elastic/elasticsearch.git", config_store.config["source"]["remote.repo.url"])
         self.assertEqual("elasticsearch", config_store.config["source"]["elasticsearch.src.subdir"])
 
         self.assertTrue("benchmarks" in config_store.config)
-        self.assertEqual("${node:root.dir}/data", config_store.config["benchmarks"]["local.dataset.cache"])
+        self.assertEqual(os.path.join(root_dir, "data"), config_store.config["benchmarks"]["local.dataset.cache"])
 
         self.assertTrue("reporting" in config_store.config)
         self.assertEqual("in-memory", config_store.config["reporting"]["datastore.type"])
@@ -765,5 +767,29 @@ def test_migrate_from_15_to_16(self):
         self.assertIn("distributions", config_file.config)
         self.assertNotIn("release.url", config_file.config["distributions"])
 
+    def test_migrate_from_16_to_17(self):
+        config_file = InMemoryConfigStore("test")
+        sample_config = {
+            "meta": {
+                "config.version": 16
+            },
+            "node": {
+                "root.dir": "/home/user/.rally/benchmarks"
+            },
+            "runtime": {
+                "java.home": "/usr/local/javas/10"
+            },
+            "benchmarks": {
+                "local.dataset.cache": "${node:root.dir}/data"
+            }
+        }
+        config_file.store(sample_config)
+        config.migrate(config_file, 16, 17, out=null_output)
+
+        self.assertTrue(config_file.backup_created)
+        self.assertEqual("17", config_file.config["meta"]["config.version"])
+        self.assertNotIn("runtime", config_file.config)
+        self.assertEqual("/home/user/.rally/benchmarks/data", config_file.config["benchmarks"]["local.dataset.cache"])
+