Processor group implementation: A wrapper to launch multiple
processors in a single processor
- trustgraph-base/trustgraph/base/processor_group.py — group runner
module. run_group(config) is the async body; run() is the
endpoint. Loads JSON or YAML config, validates that every entry
has a unique params.id, instantiates each class via importlib,
shares one TaskGroup, mirrors AsyncProcessor.launch's retry loop
and Prometheus startup.
- trustgraph-base/pyproject.toml — added [project.scripts] block
with processor-group = "trustgraph.base.processor_group:run".
Key behaviours:
- Unique id enforced up front — missing or duplicate params.id fails
fast with a clear error, preventing the Prometheus Info label
collision we flagged.
- No registry — dotted class path is the identifier; any
AsyncProcessor descendant importable at runtime is packable.
- YAML import is lazy — only pulled in if the config file ends in
.yaml/.yml, so JSON-only users don't need PyYAML installed.
- Single Prometheus server — start_http_server runs once at
startup, before the retry loop, matching launch()'s pattern.
- Retry loop — same shape as AsyncProcessor.launch: catches
ExceptionGroup from TaskGroup, logs, sleeps 4s,
retries. Fail-group semantics (one processor dying tears down the
group) — simple and surfaces bugs, as discussed.
Example config:
processors:
- class: trustgraph.extract.kg.definitions.extract.Processor
params:
id: kg-extract-definitions
- class: trustgraph.chunking.recursive.Processor
params:
id: chunker-recursive
Run with processor-group -c group.yaml.
