RUST-1588: Add RunCursorCommand

src/db.rs

@@ -501,18 +501,23 @@ impl Database {
         options: RunCursorCommandOptions,
         session: &mut ClientSession,
     ) -> Result<SessionCursor<Document>> {
+        let mut selection_criteria = SelectionCriteria::ReadPreference(options.read_preference.clone().unwrap()).into();
         match session.transaction.state {
             TransactionState::Starting | TransactionState::InProgress => {
-                if command.contains_key("readConcern") {
-                    return Err(ErrorKind::InvalidArgument {
-                        message: "Cannot set read concern after starting a transaction".into(),
+                selection_criteria = match selection_criteria {
+                    Some(selection_criteria) => Some(selection_criteria),
+                    None => {
+                        if let Some(ref options) = session.transaction.options {
+                            options.selection_criteria.clone()
+                        } else {
+                            None
+                        }
                     }
-                    .into());
-                }
+                };     
             }
             _ => {}
         }
-        let rcc = RunCommand::new(self.name().to_string(), command, options.read_preference.clone(), None)?;
+        let rcc = RunCommand::new(self.name().to_string(), command, selection_criteria, None)?;
         let rc_command = RunCursorCommand {
             run_command: rcc,
             options,

src/db/options.rs

@@ -9,7 +9,7 @@ use crate::{
     bson::{Bson, Document},
     concern::{ReadConcern, WriteConcern},
     options::{Collation, CursorType},
-    selection_criteria::SelectionCriteria,
+    selection_criteria::{SelectionCriteria, ReadPreference},
     serde_util,
 };
 
@@ -332,7 +332,7 @@ pub struct RunCursorCommandOptions {
     /// Optional string enum value, one of 'iteration' | 'cursorLifetime'.
     pub timeout_mode: Option<TimeoutMode>,
     /// The default read preference for operations.
-    pub read_preference: Option<SelectionCriteria>,
+    pub read_preference: Option<ReadPreference>,
     /// Optional string enum value, one of 'tailable' | 'tailableAwait' | 'nonTailable'.
     pub cursor_type: Option<CursorType>,
     /// Number of documents to return per batch.
@@ -343,6 +343,4 @@ pub struct RunCursorCommandOptions {
     /// Optional BSON value. Use this value to configure the comment option sent on subsequent
     /// getMore commands.
     pub comment: Option<Bson>,
-    /// The session to run this command with.
-    pub session: Option<String>,
 }

src/operation.rs

@@ -74,7 +74,7 @@ pub(crate) use run_command::RunCommand;
 pub(crate) use update::Update;
 
 const SERVER_4_2_0_WIRE_VERSION: i32 = 8;
-pub const SERVER_4_4_0_WIRE_VERSION: i32 = 9;
+const SERVER_4_4_0_WIRE_VERSION: i32 = 9;
 
 /// A trait modeling the behavior of a server side operation.
 ///