from_config constructors for blockchain objects

nucypher/blockchain/eth/chains.py

@@ -4,6 +4,7 @@ from constant_sorrow import constants
 from web3.middleware import geth_poa_middleware
 
 from nucypher.blockchain.eth.interfaces import ControlCircumflex, DeployerCircumflex
+from nucypher.config.constants import DEFAULT_INI_FILEPATH
 from nucypher.config.parsers import parse_blockchain_config
 
 
@@ -14,8 +15,7 @@ class Blockchain:
     _default_network = NotImplemented
     __default_interface_class = ControlCircumflex
 
-    test_chains = ('tester', )
-    transient_chains = test_chains + ('testrpc', 'temp')
+    test_chains = ('tester', 'temp')
     public_chains = ('mainnet', 'ropsten')
 
     class ConnectionNotEstablished(RuntimeError):
@@ -39,8 +39,25 @@ class Blockchain:
         return r.format(class_name, self.__interface)
 
     @classmethod
-    def from_config(cls) -> 'Blockchain':
-        return cls(**parse_blockchain_config())
+    def from_config(cls, filepath=None, registry_filepath: str=None) -> 'Blockchain':
+
+        filepath = filepath if filepath is not None else DEFAULT_INI_FILEPATH
+        payload = parse_blockchain_config(filepath=filepath)
+
+        interface = ControlCircumflex.from_config(filepath=filepath)
+
+        if cls._instance is not None:
+            return cls.connect()
+
+        if payload['tester']:
+            blockchain = TesterBlockchain(interface=interface,
+                                          poa=payload['poa'],
+                                          test_accounts=payload['test_accounts'],
+                                          airdrop=False)
+        else:
+            blockchain = Blockchain(interface=interface)
+
+        return blockchain
 
     @classmethod
     def connect(cls):

nucypher/blockchain/eth/interfaces.py

@@ -4,6 +4,7 @@ import os
 import warnings
 from pathlib import Path
 from typing import Tuple, List
+from urllib.parse import urlparse
 
 from constant_sorrow import constants
 from eth_utils import to_canonical_address
@@ -13,8 +14,8 @@ from web3 import Web3, WebsocketProvider, HTTPProvider, IPCProvider
 from web3.contract import Contract
 
 from nucypher.blockchain.eth.sol.compile import SolidityCompiler
-
-_DEFAULT_CONFIGURATION_DIR = os.path.join(str(Path.home()), '.nucypher')
+from nucypher.config.constants import DEFAULT_CONFIG_ROOT, DEFAULT_INI_FILEPATH, DEFAULT_SIMULATION_REGISTRY_FILEPATH
+from nucypher.config.parsers import parse_blockchain_config
 
 
 class EthereumContractRegistry:
@@ -25,7 +26,7 @@ class EthereumContractRegistry:
     WARNING: Unless you are developing NuCypher, you most likely won't ever need
     to use this.
     """
-    __default_registry_path = os.path.join(_DEFAULT_CONFIGURATION_DIR, 'registry.json')
+    __default_registry_path = os.path.join(DEFAULT_CONFIG_ROOT, 'registry.json')
 
     class RegistryError(Exception):
         pass
@@ -39,6 +40,21 @@ class EthereumContractRegistry:
     def __init__(self, registry_filepath: str=None):
         self.__registry_filepath = registry_filepath or self.__default_registry_path
 
+    @classmethod
+    def from_config(cls, filepath=None, **overrides) -> 'EthereumContractRegistry':
+        from nucypher.blockchain.eth.utilities import TemporaryEthereumContractRegistry
+
+        filepath = filepath if filepath is None else DEFAULT_INI_FILEPATH
+        payload = parse_blockchain_config(filepath=filepath)
+
+        if payload['tmp_registry']:
+            # In memory only
+            registry = TemporaryEthereumContractRegistry()
+        else:
+            registry = EthereumContractRegistry(**overrides)
+
+        return registry
+
     @property
     def registry_filepath(self):
         return self.__registry_filepath
@@ -130,9 +146,14 @@ class ControlCircumflex:
     class InterfaceError(Exception):
         pass
 
-    def __init__(self, network_name: str=None, endpoint_uri: str=None,
-                 websocket=False, ipc_path=None, timeout=None, providers: list=None,
-                 registry: EthereumContractRegistry=None, compiler: SolidityCompiler=None):
+    def __init__(self,
+                 network_name: str = None,
+                 provider_uri: str = None,
+                 providers: list = None,
+                 autoconnect: bool = True,
+                 timeout: int = None,
+                 registry: EthereumContractRegistry = None,
+                 compiler: SolidityCompiler=None) -> None:
 
         """
         A blockchain "network inerface"; The circumflex wraps entirely around the bounds of
@@ -194,16 +215,15 @@ class ControlCircumflex:
         #
         # Providers
         #
+        if provider_uri and providers:
+            raise self.InterfaceError("Pass a provider URI string, or a list of provider instances.")
+        self.provider_uri = provider_uri
+        self._providers = list() if providers is None else providers
 
         # If custom __providers are not injected...
-        self._providers = list() if providers is None else providers
-        if providers is None:
-            # Mutates self._providers
-            self.add_provider(endpoint_uri=endpoint_uri, websocket=websocket,
-                              ipc_path=ipc_path, timeout=timeout)
-
-        web3_instance = Web3(providers=self._providers)  # Instantiate Web3 object with provider
-        self.w3 = web3_instance                           # capture web3
+        self.w3 = constants.NO_BLOCKCHAIN_CONNECTION
+        if autoconnect is True:
+            self.connect(provider_uri=self.provider_uri)
 
         # if a SolidityCompiler class instance was passed, compile from solidity source code
         recompile = True if compiler is not None else False