feat: Add experimental async transport (port of PR #4572)

AGENTS.md

@@ -65,3 +65,18 @@ Do NOT edit these directly — modify source scripts instead:
 | `sentry_sdk/profiler/` | Performance profiling |
 | `tests/integrations/{name}/` | Integration test suites |
 | `scripts/populate_tox/config.py` | Test suite configuration |
+
+<!-- This section is maintained by the coding agent via lore (https://github.com/BYK/opencode-lore) -->
+## Long-term Knowledge
+
+### Gotcha
+
+<!-- lore:019cc484-f0e1-7016-a851-177fb9ad2cc4 -->
+* **AGENTS.md must be excluded from markdown linters**: AGENTS.md is auto-managed by lore and uses \`\*\` list markers and long lines that violate typical remark-lint rules (unordered-list-marker-style, maximum-line-length). When a project uses remark with \`--frail\` (warnings become errors), AGENTS.md will fail CI. Fix: add \`AGENTS.md\` to \`.remarkignore\`. This applies to any lore-managed project with markdown linting.
+
+<!-- lore:019cc40e-e56e-71e9-bc5d-545f97df732b -->
+* **Consola prompt cancel returns truthy Symbol, not false**: When a user cancels a \`consola\` / \`@clack/prompts\` confirmation prompt (Ctrl+C), the return value is \`Symbol(clack:cancel)\`, not \`false\`. Since Symbols are truthy in JavaScript, checking \`!confirmed\` will be \`false\` and the code falls through as if the user confirmed. Fix: use \`confirmed !== true\` (strict equality) instead of \`!confirmed\` to correctly handle cancel, false, and any other non-true values.
+
+<!-- lore:019cc303-e397-75b9-9762-6f6ad108f50a -->
+* **Zod z.coerce.number() converts null to 0 silently**: Zod gotchas in this codebase: (1) \`z.coerce.number()\` passes input through \`Number()\`, so \`null\` silently becomes \`0\`. Be aware if \`null\` vs \`0\` distinction matters. (2) Zod v4 \`.default({})\` short-circuits — it returns the default value without parsing through inner schema defaults. So \`.object({ enabled: z.boolean().default(true) }).default({})\` returns \`{}\`, not \`{ enabled: true }\`. Fix: provide fully-populated default objects. This affected nested config sections in src/config.ts during the v3→v4 upgrade.
+<!-- End lore-managed section -->

scripts/populate_tox/config.py

@@ -122,7 +122,7 @@
                 "pytest-asyncio",
                 "python-multipart",
                 "requests",
-                "anyio<4",
+                "anyio>=3,<5",
             ],
             # There's an incompatibility between FastAPI's TestClient, which is
             # actually Starlette's TestClient, which is actually httpx's Client.
@@ -132,6 +132,7 @@
             # FastAPI versions we use older httpx which still supports the
             # deprecated argument.
             "<0.110.1": ["httpx<0.28.0"],
+            "<0.80": ["anyio<4"],
             "py3.6": ["aiocontextvars"],
         },
     },
@@ -170,7 +171,7 @@
     "httpx": {
         "package": "httpx",
         "deps": {
-            "*": ["anyio<4.0.0"],
+            "*": ["anyio>=3,<5"],
             ">=0.16,<0.17": ["pytest-httpx==0.10.0"],
             ">=0.17,<0.19": ["pytest-httpx==0.12.0"],
             ">=0.19,<0.21": ["pytest-httpx==0.14.0"],

sentry_sdk/__init__.py

@@ -25,6 +25,7 @@
     "configure_scope",
     "continue_trace",
     "flush",
+    "flush_async",
     "get_baggage",
     "get_client",
     "get_global_scope",

sentry_sdk/api.py

@@ -58,6 +58,7 @@ def overload(x: "T") -> "T":
     "configure_scope",
     "continue_trace",
     "flush",
+    "flush_async",
     "get_baggage",
     "get_client",
     "get_global_scope",
@@ -349,6 +350,14 @@ def flush(
     return get_client().flush(timeout=timeout, callback=callback)
 
 
+@clientmethod
+async def flush_async(
+    timeout: "Optional[float]" = None,
+    callback: "Optional[Callable[[int, float], None]]" = None,
+) -> None:
+    return await get_client().flush_async(timeout=timeout, callback=callback)
+
+
 @scopemethod
 def start_span(
     **kwargs: "Any",

sentry_sdk/client.py

@@ -33,7 +33,7 @@
 from sentry_sdk.serializer import serialize
 from sentry_sdk.tracing import trace
 from sentry_sdk.tracing_utils import has_span_streaming_enabled
-from sentry_sdk.transport import BaseHttpTransport, make_transport
+from sentry_sdk.transport import HttpTransportCore, make_transport, AsyncHttpTransport
 from sentry_sdk.consts import (
     SPANDATA,
     DEFAULT_MAX_VALUE_LENGTH,
@@ -253,6 +253,12 @@
     def flush(self, *args: "Any", **kwargs: "Any") -> None:
         return None
 
+    async def close_async(self, *args: "Any", **kwargs: "Any") -> None:
+        return None
+
+    async def flush_async(self, *args: "Any", **kwargs: "Any") -> None:
+        return None
+
     def __enter__(self) -> "BaseClient":
         return self
 
@@ -474,7 +480,7 @@
             or self.metrics_batcher
             or self.span_batcher
             or has_profiling_enabled(self.options)
-            or isinstance(self.transport, BaseHttpTransport)
+            or isinstance(self.transport, HttpTransportCore)
         ):
             # If we have anything on that could spawn a background thread, we
             # need to check if it's safe to use them.
@@ -1001,6 +1007,28 @@
 
         return self.integrations.get(integration_name)
 
+    def _close_components(self) -> None:
+        """Kill all client components in the correct order."""
+        self.session_flusher.kill()
+        if self.log_batcher is not None:
+            self.log_batcher.kill()
+        if self.metrics_batcher is not None:
+            self.metrics_batcher.kill()
+        if self.span_batcher is not None:
+            self.span_batcher.kill()
+        if self.monitor:
+            self.monitor.kill()
+
+    def _flush_components(self) -> None:
+        """Flush all client components."""
+        self.session_flusher.flush()
+        if self.log_batcher is not None:
+            self.log_batcher.flush()
+        if self.metrics_batcher is not None:
+            self.metrics_batcher.flush()
+        if self.span_batcher is not None:
+            self.span_batcher.flush()
+
     def close(
         self,
         timeout: "Optional[float]" = None,
@@ -1011,19 +1039,45 @@
         semantics as :py:meth:`Client.flush`.
         """
         if self.transport is not None:
-            self.flush(timeout=timeout, callback=callback)
-            self.session_flusher.kill()
-            if self.log_batcher is not None:
-                self.log_batcher.kill()
-            if self.metrics_batcher is not None:
-                self.metrics_batcher.kill()
-            if self.span_batcher is not None:
-                self.span_batcher.kill()
-            if self.monitor:
-                self.monitor.kill()
+            if isinstance(self.transport, AsyncHttpTransport) and hasattr(
+                self.transport, "loop"
+            ):
+                logger.warning(
+                    "close() used with AsyncHttpTransport. "
+                    "Prefer close_async() for graceful async shutdown. "
+                    "Performing synchronous best-effort cleanup."
+                )
+            else:
+                self.flush(timeout=timeout, callback=callback)
+            self._close_components()
             self.transport.kill()
             self.transport = None
 
+    async def close_async(
+        self,
+        timeout: "Optional[float]" = None,
+        callback: "Optional[Callable[[int, float], None]]" = None,
+    ) -> None:
+        """
+        Asynchronously close the client and shut down the transport. Arguments have the same
+        semantics as :py:meth:`Client.flush_async`.
+        """
+        if self.transport is not None:
+            if not (
+                isinstance(self.transport, AsyncHttpTransport)
+                and hasattr(self.transport, "loop")
+            ):
+                logger.debug(
+                    "close_async() used with non-async transport, aborting. Please use close() instead."
+                )
+                return
+            await self.flush_async(timeout=timeout, callback=callback)
+            self._close_components()
+            kill_task = self.transport.kill()  # type: ignore
+            if kill_task is not None:
+                await kill_task
+            self.transport = None
+
     def flush(
         self,
         timeout: "Optional[float]" = None,
@@ -1037,23 +1091,59 @@
         :param callback: Is invoked with the number of pending events and the configured timeout.
         """
         if self.transport is not None:
+            if isinstance(self.transport, AsyncHttpTransport) and hasattr(
+                self.transport, "loop"
+            ):
+                logger.warning(
+                    "flush() used with AsyncHttpTransport. Please use flush_async() instead."
+                )
+                return
             if timeout is None:
                 timeout = self.options["shutdown_timeout"]
-            self.session_flusher.flush()
-            if self.log_batcher is not None:
-                self.log_batcher.flush()
-            if self.metrics_batcher is not None:
-                self.metrics_batcher.flush()
-            if self.span_batcher is not None:
-                self.span_batcher.flush()
+            self._flush_components()
+
             self.transport.flush(timeout=timeout, callback=callback)
 
+    async def flush_async(
+        self,
+        timeout: "Optional[float]" = None,
+        callback: "Optional[Callable[[int, float], None]]" = None,
+    ) -> None:
+        """
+        Asynchronously wait for the current events to be sent.
+
+        :param timeout: Wait for at most `timeout` seconds. If no `timeout` is provided, the `shutdown_timeout` option value is used.
+
+        :param callback: Is invoked with the number of pending events and the configured timeout.
+        """
+        if self.transport is not None:
+            if not (
+                isinstance(self.transport, AsyncHttpTransport)
+                and hasattr(self.transport, "loop")
+            ):
+                logger.debug(
+                    "flush_async() used with non-async transport, aborting. Please use flush() instead."
+                )
+                return
+            if timeout is None:
+                timeout = self.options["shutdown_timeout"]
+            self._flush_components()
+            flush_task = self.transport.flush(timeout=timeout, callback=callback)  # type: ignore
+            if flush_task is not None:
+                await flush_task
+
     def __enter__(self) -> "_Client":
         return self
 
     def __exit__(self, exc_type: "Any", exc_value: "Any", tb: "Any") -> None:
         self.close()
 
+    async def __aenter__(self) -> "_Client":
+        return self
+
+    async def __aexit__(self, exc_type: "Any", exc_value: "Any", tb: "Any") -> None:
+        await self.close_async()
+
 
 from typing import TYPE_CHECKING
 

sentry_sdk/consts.py

@@ -79,6 +79,7 @@ class CompressionAlgo(Enum):
             "transport_compression_algo": Optional[CompressionAlgo],
             "transport_num_pools": Optional[int],
             "transport_http2": Optional[bool],
+            "transport_async": Optional[bool],
             "enable_logs": Optional[bool],
             "before_send_log": Optional[Callable[[Log, Hint], Optional[Log]]],
             "enable_metrics": Optional[bool],