Add settings renderer, cli flag and config handling

chainsyncer/cli/__init__.py

@@ -0,0 +1,12 @@
+# standard imports
+import os
+
+# local imports
+from .base import *
+from .arg import process_flags
+from .config import process_config
+
+
+__script_dir = os.path.dirname(os.path.realpath(__file__))
+data_dir = os.path.join(os.path.dirname(__script_dir), 'data')
+config_dir = os.path.join(data_dir, 'config')

chainsyncer/cli/arg.py

@@ -0,0 +1,12 @@
+# local imports
+from .base import SyncFlag
+
+
+def process_flags(argparser, flags):
+
+    if flags & SyncFlag.RANGE > 0:
+        argparser.add_argument('--offset', type=int, help='Block to start sync from. Default is start of history (0).')
+        argparser.add_argument('--until', type=int, default=-1, help='Block to stop sync on. Default is stop at block height of first run.')
+    if flags & SyncFlag.HEAD > 0:
+        argparser.add_argument('--head', action='store_true', help='Start from latest block as offset')
+        argparser.add_argument('--keep-alive', action='store_true', help='Do not stop syncing when caught up')

chainsyncer/cli/base.py

@@ -0,0 +1,7 @@
+# standard imports
+import enum
+
+
+class SyncFlag(enum.IntEnum):
+    RANGE = 1
+    HEAD = 2

chainsyncer/cli/config.py

@@ -0,0 +1,17 @@
+# external imports
+from chainsyncer.cli import SyncFlag
+
+
+def process_config(config, args, flags):
+        args_override = {}
+        if flags & SyncFlag.RANGE:
+            args_override['SYNCER_OFFSET'] = getattr(args, 'offset')
+            args_override['SYNCER_LIMIT'] = getattr(args, 'until')
+
+        config.dict_override(args_override, 'local cli args')
+
+        if flags & SyncFlag.HEAD:
+            config.add(getattr(args, 'keep_alive'), '_KEEP_ALIVE')
+            config.add(getattr(args, 'head'), '_HEAD')
+
+        return config

chainsyncer/data/config/syncer.ini

@@ -0,0 +1,3 @@
+[syncer]
+offset = 0
+limit = 0

chainsyncer/paths.py

@@ -0,0 +1 @@
+

chainsyncer/settings.py

@@ -0,0 +1,51 @@
+# standard imports
+import logging
+
+# external imports
+from chainlib.eth.block import block_latest
+from hexathon import (
+        to_int as hex_to_int,
+        strip_0x,
+        )
+
+logg = logging.getLogger(__name__)
+
+
+class ChainsyncerSettings:
+
+    def process_sync_range(self, config):
+        o = block_latest()
+        r = self.o['RPC'].do(o)
+        block_offset = int(strip_0x(r), 16) + 1
+        logg.info('network block height at startup is {}'.format(block_offset))
+
+        keep_alive = False
+        session_block_offset = 0
+        block_limit = 0
+        until = 0
+
+        if config.true('_HEAD'):
+            self.o['SYNCER_OFFSET'] = block_offset
+            self.o['SYNCER_LIMIT'] = -1
+            return
+
+        session_block_offset = int(config.get('SYNCER_OFFSET'))
+        until = int(config.get('SYNCER_LIMIT'))
+
+        if until > 0:
+            if until <= session_block_offset:
+                raise ValueError('sync termination block number must be later than offset ({} >= {})'.format(session_block_offset, until))
+            block_limit = until
+        elif until == -1:
+            keep_alive = True
+
+        if session_block_offset == -1:
+            session_block_offset = block_offset
+        elif config.true('_KEEP_ALIVE'):
+            block_limit = -1
+        else:
+            if block_limit == 0:
+                block_limit = block_offset
+    
+        self.o['SYNCER_OFFSET'] = session_block_offset
+        self.o['SYNCER_LIMIT'] = block_limit

chainsyncer/store/mem.py

@@ -32,3 +32,9 @@ class SyncMemStore(SyncStore):
 
     def get_target(self):
         return self.target
+
+
+    def stop(self, item):
+        if item != None:
+            super(SyncRocksDbStore, self).stop(item)
+        logg.info('I am an in-memory only state store. I am shutting down now, so all state will now be discarded.')