MODULE REFERENCE

daq

anomx.data.sources.daq

Optional, isolated readers for scalar fields in native FLASH/XFEL DAQ files.

DaqReadError

DaqReadError

Bases: RuntimeError

The optional native reader failed, timed out or returned an unsupported record.

classView source ↗

Signature parameters
Parameter	Type	Default
`timestamp`	`float`	`required`
`event_id`	`int`	`required`
`channel`	`str`	`required`
`values`	`Mapping[str, float \| None]`	`required`
`invalid_fields`	`Mapping[str, str]`	`required`
`field_metadata`	`Mapping[str, Mapping[str, Any]]`	`required`
`source_path`	`str`	`required`
`dataset_version`	`str`	`required`
`record_index`	`int`	`required`

iter_daq_records

iter_daq_records(source: MountedSource, *, channel: str, fields: Mapping[str, int], experiment: str, linac: str, python_executable: str | None = None, environment: Mapping[str, str] | None = None, batch_size: int = 128, timeout_seconds: float = 60.0, limit: int | None = None) -> Iterator[DaqRecord]

Read explicit scalar subchannels using one isolated native process per source.

fields maps output aliases to native subchannel indices. Actual native names/types are retained, never guessed. Nonfinite values become None with an explicit invalid_fields reason. Timestamps and macropulse IDs are preserved numerically; their scientific interpretation belongs to the caller. Missing requested fields or unsupported shapes fail closed.

python_executable can select a separate Python with a compatible pydaq ABI. environment extends its environment (for example library paths). No pydaq dependency is imported in the parent. Data is transferred in batches through a bounded pipe/queue, not a new process per record. timeout_seconds bounds waiting for startup, each batch or completion. Source size/time/identity are checked by MountedSource.open around the read. Close the iterator explicitly when stopping early, e.g. with contextlib.closing. No content hash is implied by metadata validation.

Signature parameters
Parameter	Type	Default
`source`	`MountedSource`	`required`
`channel`keyword only	`str`	`required`
`fields`keyword only	`Mapping[str, int]`	`required`
`experiment`keyword only	`str`	`required`
`linac`keyword only	`str`	`required`
`python_executable`keyword only	`str \| None`	`None`
`environment`keyword only	`Mapping[str, str] \| None`	`None`
`batch_size`keyword only	`int`	`128`
`timeout_seconds`keyword only	`float`	`60.0`
`limit`keyword only	`int \| None`	`None`

Returns Iterator[DaqRecord]

DaqReadError

DaqRecord

Members

iter_daq_records