Reduce helper apis

scyllaconn/src/config.rs

@@ -0,0 +1,50 @@
+use crate::errconv::ErrConv;
+use err::Error;
+use futures_util::StreamExt;
+use netpod::{log::*, Channel, ScalarType, Shape};
+use netpod::{ChannelConfigQuery, ChannelConfigResponse};
+use scylla::Session as ScySession;
+use std::sync::Arc;
+
+// TODO unused, table in postgres.
+pub async fn config_from_scylla(chq: ChannelConfigQuery, scy: Arc<ScySession>) -> Result<ChannelConfigResponse, Error> {
+    let cql = "select series, scalar_type, shape_dims from series_by_channel where facility = ? and channel_name = ?";
+    let mut it = scy
+        .query_iter(cql, (chq.channel.backend(), chq.channel.name()))
+        .await
+        .err_conv()?;
+    let mut rows = Vec::new();
+    while let Some(row) = it.next().await {
+        let row = row.err_conv()?;
+        let cols = row.into_typed::<(i64, i32, Vec<i32>)>().err_conv()?;
+        let scalar_type = ScalarType::from_scylla_i32(cols.1)?;
+        let shape = Shape::from_scylla_shape_dims(&cols.2)?;
+        let channel = Channel {
+            series: Some(cols.0 as _),
+            backend: chq.channel.backend().into(),
+            name: chq.channel.name().into(),
+        };
+        let res = ChannelConfigResponse {
+            channel,
+            scalar_type,
+            byte_order: None,
+            shape,
+        };
+        info!("config_from_scylla: {res:?}");
+        rows.push(res);
+    }
+    if rows.is_empty() {
+        return Err(Error::with_public_msg_no_trace(format!(
+            "can not find config for channel {:?}",
+            chq.channel
+        )));
+    } else {
+        if rows.len() > 1 {
+            error!(
+                "Found multiple configurations for channel  {:?}  {:?}",
+                chq.channel, rows
+            );
+        }
+        Ok(rows.pop().unwrap())
+    }
+}

scyllaconn/src/scyllaconn.rs

@@ -1,4 +1,5 @@
 pub mod bincache;
+pub mod config;
 pub mod errconv;
 pub mod events;