From be269a7793d2779062bacbb2dd5b9f62b2d6e5e9 Mon Sep 17 00:00:00 2001 From: Tom Willemsen Date: Mon, 4 Sep 2023 15:21:57 +0100 Subject: [PATCH] NDArray: More explicit docs --- ophyd/v2/_p4p.py | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/ophyd/v2/_p4p.py b/ophyd/v2/_p4p.py index 455b15059..cdd3edc81 100644 --- a/ophyd/v2/_p4p.py +++ b/ophyd/v2/_p4p.py @@ -58,13 +58,13 @@ def descriptor(self, source: str, value) -> Descriptor: def metadata_fields(self) -> List[str]: """ - PVA request string for metadata. + Fields to request from PVA for metadata. """ return ["alarm", "timeStamp"] def value_fields(self) -> List[str]: """ - PVA request string for value only. + Fields to request from PVA for the value. """ return ["value"] @@ -260,6 +260,10 @@ async def get_descriptor(self) -> Descriptor: return self.converter.descriptor(self.source, value) def _pva_request_string(self, fields: List[str]) -> str: + """ + Converts a list of requested fields into a PVA request string which can be + passed to p4p. + """ return f"field({','.join(fields)})" async def get_reading(self) -> Reading: @@ -283,8 +287,12 @@ def set_callback(self, callback: Optional[ReadingValueCallback[T]]) -> None: async def async_callback(v): callback(self.converter.reading(v), self.converter.value(v)) + request: str = self._pva_request_string( + self.converter.value_fields() + self.converter.metadata_fields() + ) + self.subscription = self.ctxt.monitor( - self.read_pv, async_callback, request="field(value,alarm,timeStamp)" + self.read_pv, async_callback, request=request ) else: if self.subscription: