[c++] Improve exception-handling for query futures

.github/workflows/libtiledb-ci.yml

@@ -21,7 +21,7 @@ jobs:
     - name: Build libTileDB-SOMA
       run: TILEDBSOMA_COVERAGE="--coverage" ./scripts/bld --no-tiledb-deprecated=true
     - name: Run libTileDB-SOMA unittests
-      run: ctest --test-dir build/libtiledbsoma -C Release --verbose --rerun-failed --output-on-failur
+      run: ctest --test-dir build/libtiledbsoma -C Release --verbose --rerun-failed --output-on-failure
     - name: Upload coverage to Codecov
       uses: codecov/codecov-action@v3
       with:

libtiledbsoma/src/soma/managed_query.cc

@@ -55,9 +55,6 @@ ManagedQuery::ManagedQuery(
 }
 
 void ManagedQuery::close() {
-    if (query_future_.valid()) {
-        query_future_.get();
-    }
     array_->close();
 }
 
@@ -292,8 +289,13 @@ void ManagedQuery::submit_read() {
     query_submitted_ = true;
     query_future_ = std::async(std::launch::async, [&]() {
         LOG_DEBUG("[ManagedQuery] submit thread start");
-        query_->submit();
+        try {
+            query_->submit();
+        } catch (const std::exception& e) {
+            return StatusAndException(false, e.what());
+        }
         LOG_DEBUG("[ManagedQuery] submit thread done");
+        return StatusAndException(true, "success");
     });
 }
 
@@ -305,6 +307,17 @@ std::shared_ptr<ArrayBuffers> ManagedQuery::results() {
     if (query_future_.valid()) {
         LOG_DEBUG(fmt::format("[ManagedQuery] [{}] Waiting for query", name_));
         query_future_.wait();
+        LOG_DEBUG(
+            fmt::format("[ManagedQuery] [{}] Done waiting for query", name_));
+
+        auto retval = query_future_.get();
+        if (!retval.succeeded()) {
+            throw TileDBSOMAError(fmt::format(
+                "[ManagedQuery] [{}] Query FAILED: {}",
+                name_,
+                retval.message()));
+        }
+
     } else {
         throw TileDBSOMAError(
             fmt::format("[ManagedQuery] [{}] 'query_future_' invalid", name_));

libtiledbsoma/src/soma/managed_query.h

@@ -47,6 +47,26 @@ namespace tiledbsoma {
 
 using namespace tiledb;
 
+// Probably we should just use a std::tuple here
+class StatusAndException {
+   public:
+    StatusAndException(bool succeeded, std::string message)
+        : succeeded_(succeeded)
+        , message_(message) {
+    }
+
+    bool succeeded() {
+        return succeeded_;
+    }
+    std::string message() {
+        return message_;
+    }
+
+   private:
+    bool succeeded_;
+    std::string message_;
+};
+
 class ManagedQuery {
    public:
     //===================================================================
@@ -411,7 +431,7 @@ class ManagedQuery {
     bool query_submitted_ = false;
 
     // Future for asyncronous query
-    std::future<void> query_future_;
+    std::future<StatusAndException> query_future_;
 };
 };  // namespace tiledbsoma