chore: fix get json meta coredump when json meta is null

Author: zitsen

taos-optin/src/raw/mod.rs

@@ -10,7 +10,7 @@ use std::sync::{Arc, Mutex, Weak};
 use std::task::{Context, Poll, Waker};
 
 use dlopen2::raw::Library;
-use taos_query::common::{c_field_t, raw_data_t, RawData, SmlData};
+use taos_query::common::{c_field_t, raw_data_t, JsonMeta, RawData, SmlData};
 use taos_query::prelude::{Code, Field, Precision, RawError};
 use taos_query::tmq::Assignment;
 use taos_query::RawBlock;
@@ -1763,13 +1763,25 @@ impl RawRes {
         }
     }
     #[inline]
-    pub(crate) fn tmq_get_json_meta(&self) -> String {
+    pub(crate) fn tmq_get_json_meta(&self) -> Result<JsonMeta, RawError> {
         unsafe {
             let meta = (self.c.tmq.as_ref().unwrap().tmq_get_json_meta)(self.as_ptr());
-            let meta_cstr = CStr::from_ptr(meta).to_string_lossy().into_owned();
-            (self.c.tmq.as_ref().unwrap().tmq_free_json_meta)(meta);
-            tracing::debug!(json = meta_cstr, "Received TMQ json meta");
-            meta_cstr
+            if meta.is_null() {
+                return Err(RawError::from_string("tmq_get_json_meta returns null"));
+            }
+
+            let meta_cstr = CStr::from_ptr(meta);
+            match serde_json::from_slice(meta_cstr.to_bytes()) {
+                Ok(json_meta) => {
+                    tracing::trace!(json = %meta_cstr.to_string_lossy(), "Received TMQ json meta");
+                    (self.c.tmq.as_ref().unwrap().tmq_free_json_meta)(meta);
+                    Ok(json_meta)
+                }
+                Err(err) => {
+                    (self.c.tmq.as_ref().unwrap().tmq_free_json_meta)(meta);
+                    Err(RawError::from_string(err.to_string()))
+                }
+            }
         }
     }
 

taos-optin/src/tmq/mod.rs

@@ -319,13 +319,10 @@ impl AsyncOnSync for Meta {}
 impl IsMeta for Meta {
     fn as_raw_meta(&self) -> RawResult<RawMeta> {
         self.res.tmq_get_raw()
-        // Ok(unsafe { std::mem::transmute(self.raw.clone()) })
     }
 
     fn as_json_meta(&self) -> RawResult<taos_query::common::JsonMeta> {
-        let meta = serde_json::from_slice(self.res.tmq_get_json_meta().as_bytes())
-            .map_err(|err| RawError::from_string(err.to_string()))?;
-        Ok(meta)
+        self.res.tmq_get_json_meta()
     }
 }
 impl Meta {
@@ -334,17 +331,13 @@ impl Meta {
         Self { res }
     }
 
-    // pub fn to_raw(&self) -> raw_data_t {
-    //     self.raw.as_raw_data_t()
-    // }
-
+    #[cfg(test)]
     pub fn to_json(&self) -> serde_json::Value {
-        serde_json::from_slice(self.res.tmq_get_json_meta().as_bytes())
-            .expect("meta json should always be valid json format")
-    }
-
-    pub fn to_sql(&self) -> String {
-        todo!()
+        self.res
+            .tmq_get_json_meta()
+            .ok()
+            .and_then(|v| serde_json::to_value(v).ok())
+            .unwrap_or_else(|| serde_json::Value::Null)
     }
 }
 #[derive(Debug)]