2021-07-20 18:50:43 -04:00

81 lines
2.0 KiB
Python

from itertools import groupby
from typing import Iterable, List
from mev_inspect.schemas import Trace, NestedTrace
def as_nested_traces(traces: Iterable[Trace]) -> List[NestedTrace]:
nested_traces = []
sorted_by_transaction_hash = sorted(traces, key=_get_transaction_hash)
for _, transaction_traces in groupby(
sorted_by_transaction_hash, _get_transaction_hash
):
nested_traces += _as_nested_traces_by_transaction(transaction_traces)
return nested_traces
def _get_transaction_hash(trace) -> str:
return trace.transaction_hash
def _as_nested_traces_by_transaction(traces: Iterable[Trace]) -> List[NestedTrace]:
"""
Turns a list of Traces into a a tree of NestedTraces
using their trace addresses
Right now this has an exponential (?) runtime because we rescan
most traces at each level of tree depth
TODO to write a better implementation if it becomes a bottleneck
Should be doable in linear time
"""
nested_traces = []
parent = None
children: List[Trace] = []
sorted_traces = sorted(traces, key=lambda t: t.trace_address)
for trace in sorted_traces:
if parent is None:
parent = trace
children = []
continue
elif not _is_subtrace(trace, parent):
nested_traces.append(
NestedTrace(
trace=parent,
subtraces=as_nested_traces(children),
)
)
parent = trace
children = []
else:
children.append(trace)
if parent is not None:
nested_traces.append(
NestedTrace(
trace=parent,
subtraces=as_nested_traces(children),
)
)
return nested_traces
def _is_subtrace(trace: Trace, parent: Trace):
parent_trace_length = len(parent.trace_address)
if len(trace.trace_address) > parent_trace_length:
prefix = trace.trace_address[:parent_trace_length]
return prefix == parent.trace_address
return False