Only use conda if conda is present

binaries/cli/src/attach.rs

@@ -44,7 +44,7 @@ pub fn attach_dataflow(
                         let path = resolve_path(&python_source.source, &working_dir)
                             .wrap_err_with(|| {
                                 format!("failed to resolve node source `{}`", python_source.source)
-                        })?;
+                            })?;
                         node_path_lookup
                             .insert(path, (dataflow_id, node.id.clone(), Some(op.id.clone())));
                     }

binaries/daemon/src/spawn.rs

@@ -20,7 +20,7 @@ use dora_node_api::{
     arrow_utils::{copy_array_into_sample, required_data_size},
     Metadata,
 };
-use eyre::WrapErr;
+use eyre::{ContextCompat, WrapErr};
 use std::{
     env::consts::EXE_EXTENSION,
     path::{Path, PathBuf},

binaries/runtime/src/operator/python.rs

@@ -3,7 +3,7 @@
 use super::{OperatorEvent, StopReason};
 use dora_core::{
     config::{NodeId, OperatorId},
-    descriptor::{source_is_url, Descriptor},
+    descriptor::{source_is_url, Descriptor, PythonSource},
 };
 use dora_download::download_file;
 use dora_node_api::Event;
@@ -35,13 +35,13 @@ fn traceback(err: pyo3::PyErr) -> eyre::Report {
 pub fn run(
     node_id: &NodeId,
     operator_id: &OperatorId,
-    source: &str,
+    python_source: &PythonSource,
     events_tx: Sender<OperatorEvent>,
     incoming_events: flume::Receiver<Event>,
     init_done: oneshot::Sender<Result<()>>,
     dataflow_descriptor: &Descriptor,
 ) -> eyre::Result<()> {
-    let path = if source_is_url(source) {
+    let path = if source_is_url(&python_source.source) {
         let target_path = Path::new("build")
             .join(node_id.to_string())
             .join(format!("{}.py", operator_id));
@@ -49,11 +49,11 @@ pub fn run(
         let rt = tokio::runtime::Builder::new_current_thread()
             .enable_all()
             .build()?;
-        rt.block_on(download_file(source, &target_path))
+        rt.block_on(download_file(&python_source.source, &target_path))
             .wrap_err("failed to download Python operator")?;
         target_path
     } else {
-        Path::new(source).to_owned()
+        Path::new(&python_source.source).to_owned()
     };
 
     if !path.exists() {

examples/python-operator-dataflow/dataflow.yml

@@ -19,9 +19,7 @@ nodes:
 
   - id: plot
     operator:
-      python: 
-        source: plot.py
-        conda_env: base
+      python: plot.py
       inputs:
         image: webcam/image
         bbox: object_detection/bbox

examples/python-operator-dataflow/dataflow_conda.yml

@@ -0,0 +1,28 @@
+nodes:
+  - id: webcam
+    operator:
+      python: webcam.py
+      inputs:
+        tick: dora/timer/millis/50
+      outputs:
+        - image
+
+  - id: object_detection
+    operator:
+      send_stdout_as: stdout
+      python: object_detection.py
+      inputs:
+        image: webcam/image
+      outputs:
+        - bbox
+        - stdout
+
+  - id: plot
+    operator:
+      python: 
+        source: plot.py
+        conda_env: base
+      inputs:
+        image: webcam/image
+        bbox: object_detection/bbox
+        assistant_message: object_detection/stdout

examples/python-operator-dataflow/run.rs

@@ -73,8 +73,13 @@ async fn main() -> eyre::Result<()> {
     .await
     .context("maturin develop failed")?;
 
-    let dataflow = Path::new("dataflow.yml");
-    run_dataflow(dataflow).await?;
+    if std::env::var("CONDA_EXE").is_ok() {
+        let dataflow = Path::new("dataflow.yml");
+        run_dataflow(dataflow).await?;
+    } else {
+        let dataflow = Path::new("dataflow_conda.yml");
+        run_dataflow(dataflow).await?;
+    }
 
     Ok(())
 }