fix: start WritesRetry max_retry_time at a request's first failure

CHANGELOG.md

@@ -8,6 +8,7 @@
 1. [#714](https://github.com/influxdata/influxdb-client-python/pull/714): Implement `WriteApi.flush()` to force pending batch writes without disposing the API (mirrors C#/Java batch writer).
 1. [#715](https://github.com/influxdata/influxdb-client-python/pull/715): Accept numeric zero for `RangeThreshold.min`/`max` and greater/lesser `value` (identity checks vs `None`, not truthiness); cover create-check serialization.
 1. [#720](https://github.com/influxdata/influxdb-client-python/pull/720): Prevent the `api_client` class from raising exceptions while the Python interpreter clears the client state during shutdown.
+1. [#725](https://github.com/influxdata/influxdb-client-python/pull/725): Start the `WritesRetry` `max_retry_time` at a request's first failure, so a strategy passed as `retries` to `InfluxDBClient` keeps retrying after `max_retry_time` has passed since it was created.
 
 ## 1.50.0 [2026-01-23]
 

influxdb_client/client/write/retry.py

@@ -51,7 +51,10 @@ def __init__(self, jitter_interval=0, max_retry_delay=125, exponential_base=2, m
         self.max_retry_delay = max_retry_delay
         self.max_retry_time = max_retry_time
         self.exponential_base = exponential_base
-        self.retry_timeout = datetime.now() + timedelta(seconds=max_retry_time)
+        # Deadline for retrying the current request. It is set when a request
+        # first fails, not here: one instance can serve many requests, e.g. when
+        # passed as ``retries`` to ``InfluxDBClient``.
+        self.retry_timeout = None
         self.retry_callback = retry_callback
 
     def new(self, **kw):
@@ -118,10 +121,15 @@ def get_retry_after(self, response):
 
     def increment(self, method=None, url=None, response=None, error=None, _pool=None, _stacktrace=None):
         """Return a new Retry object with incremented retry counters."""
-        if self.retry_timeout < datetime.now():
+        retry_timeout = self.retry_timeout
+        if retry_timeout is None:
+            # First failure of a request: its retry time starts now.
+            retry_timeout = datetime.now() + timedelta(seconds=self.max_retry_time)
+        if retry_timeout <= datetime.now():
             raise MaxRetryError(_pool, url, error or ResponseError("max_retry_time exceeded"))
 
         new_retry = super().increment(method, url, response, error, _pool, _stacktrace)
+        new_retry.retry_timeout = retry_timeout
 
         if response is not None:
             parsed_error = InfluxDBError(response=response)

tests/test_WritesRetry.py

@@ -55,6 +55,33 @@ def test_backoff_max_time(self):
 
         self.assertEqual("max_retry_time exceeded", exception.reason.args[0])
 
+    def test_max_retry_time_starts_at_first_failure(self):
+        # A strategy passed as ``retries`` to InfluxDBClient lives as long as the client.
+        retry = NonRandomMinWritesRetry(max_retry_time=1)
+        time.sleep(1.5)
+
+        # The first failure of a request made after max_retry_time is still retried.
+        retry = retry.increment()
+        self.assertEqual(retry.is_exhausted(), False)
+        self.assertEqual(retry.total, 4)
+
+    def test_max_retry_time_is_per_request(self):
+        base = NonRandomMinWritesRetry(max_retry_time=1)
+
+        first_request = base.increment()
+        time.sleep(1.5)
+        with self.assertRaises(MaxRetryError) as cm:
+            first_request.increment()
+        self.assertEqual("max_retry_time exceeded", cm.exception.reason.args[0])
+
+        # Another request made with the same strategy gets its own max_retry_time.
+        second_request = base.increment()
+        self.assertEqual(second_request.total, 4)
+
+    def test_max_retry_time_zero_disables_retry(self):
+        with self.assertRaises(MaxRetryError):
+            WritesRetry(max_retry_time=0).increment()
+
     def test_backoff_start_range(self):
         retry = NonRandomMinWritesRetry(total=5, retry_interval=1, exponential_base=2,
                                         max_retry_delay=550)