Updated env variable MACOSX_DEPLOYMENT_TARGET to 15 for 3.13 python wheel generation (#2095)

* Updated env variable MACOSX_DEPLOYMENT_TARGET to 15 for 3.13 python wheel generation
* Updated migration docs to include that the *assign/*unassign calls are optional

Author: pranavrth

.semaphore/semaphore.yml

@@ -50,7 +50,7 @@ blocks:
         - name: CIBW_SKIP
           value: cp36-* cp37-* cp38-* cp39-* cp310-* cp311-* cp312-*
         - name: CIBW_ENVIRONMENT_MACOS
-          value: MACOSX_DEPLOYMENT_TARGET=13
+          value: MACOSX_DEPLOYMENT_TARGET=15
       jobs:
         - name: Build
           commands:
@@ -98,7 +98,7 @@ blocks:
         - name: CIBW_SKIP
           value: cp38-* cp39-* cp310-* cp311-* cp312-*
         - name: CIBW_ENVIRONMENT_MACOS
-          value: MACOSX_DEPLOYMENT_TARGET=13
+          value: MACOSX_DEPLOYMENT_TARGET=15
       jobs:
         - name: Build
           commands:

docs/kip-848-migration-guide.md

@@ -46,10 +46,11 @@ All [KIP-848](https://cwiki.apache.org/confluence/display/KAFKA/KIP-848%3A+The+N
 ## Rebalance Callback Changes
 
 - The **protocol is fully incremental** in KIP-848.
-- In the **rebalance callbacks**, you **must use**:
+- In the **rebalance callbacks**, you **must only use** (optional - if not used, client will handle it internally):
   - `consumer.incremental_assign(partitions)` to assign new partitions
   - `consumer.incremental_unassign(partitions)` to revoke partitions
 - **Do not** use `consumer.assign()` or `consumer.unassign()` when using `group.protocol='consumer'` (KIP-848).
+- If you don't provide incremental assign/unassign inside rebalance callbacks, the client will automatically use incremental assign/unassign internally.
 - ⚠️ The `partitions` list passed to `incremental_assign()` and `incremental_unassign()` contains only the **incremental changes** — partitions being **added** or **revoked** — **not the full assignment**, as was the case with `assign()` in the classic protocol.
 - All assignors under KIP-848 are now **sticky**, including `range`, which was **not sticky** in the classic protocol.
 
@@ -131,11 +132,11 @@ group.protocol=consumer
 def on_assign(consumer, partitions):
     # Full partition list is provided under the classic protocol
     print(f"[Classic] Assigned partitions: {partitions}")
-    consumer.assign(partitions)
+    consumer.assign(partitions) # Optional: client handles if not used
 
 def on_revoke(consumer, partitions):
     print(f"[Classic] Revoked partitions: {partitions}")
-    consumer.unassign()
+    consumer.unassign() # Optional: client handles if not used
 ```
 
 ## Incremental Assignor (Including Range in Consumer / KIP-848, Any Protocol)
@@ -145,11 +146,11 @@ def on_revoke(consumer, partitions):
 def on_assign(consumer, partitions):
     # Only incremental partitions are passed here (not full list)
     print(f"[KIP-848] Incrementally assigning: {partitions}")
-    consumer.incremental_assign(partitions)
+    consumer.incremental_assign(partitions) # Optional: client handles if not used
 
 def on_revoke(consumer, partitions):
     print(f"[KIP-848] Incrementally revoking: {partitions}")
-    consumer.incremental_unassign(partitions)
+    consumer.incremental_unassign(partitions) # Optional: client handles if not used
 ```
 
 **Note:** The `partitions` list contains **only partitions being added or revoked**, not the full partition list as in the classic `consumer.assign()`.
@@ -168,7 +169,7 @@ def on_revoke(consumer, partitions):
 3.  Set `group.protocol=consumer`
 4.  Optionally set `group.remote.assignor`; leave unspecified for broker-controlled (default: `uniform`), valid options: `uniform` or `range`
 5.  Replace deprecated configs with new ones
-6.  Update rebalance callbacks to **incremental APIs only**
+6.  Update rebalance callbacks to **incremental APIs only** (if used)
 7.  Review static membership handling (`group.instance.id`)
 8.  Ensure proper shutdown to avoid fencing issues
 9.  Adjust error handling for unknown topics and authorization failures

docs/kip-848-migration-guide.rst

@@ -67,14 +67,15 @@ Rebalance Callback Changes
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 -  The **protocol is fully incremental** in KIP-848.
--  In the **rebalance callbacks**, you **must use**:
+-  In the **rebalance callbacks**, you **must only use** (optional - if not used, client will handle it internally):
 
    -  ``consumer.incremental_assign(partitions)`` to assign new
       partitions
    -  ``consumer.incremental_unassign(partitions)`` to revoke partitions
 
 -  **Do not** use ``consumer.assign()`` or ``consumer.unassign()`` when
    using ``group.protocol='consumer'`` (KIP-848).
+-  If you don't provide incremental assign/unassign inside rebalance callbacks, the client will automatically use incremental assign/unassign internally.
 -  ⚠️ The ``partitions`` list passed to ``incremental_assign()`` and
    ``incremental_unassign()`` contains only the **incremental changes**
    — partitions being **added** or **revoked** — **not the full
@@ -199,11 +200,11 @@ Range Assignor (Classic)
    def on_assign(consumer, partitions):
        # Full partition list is provided under the classic protocol
        print(f"[Classic] Assigned partitions: {partitions}")
-       consumer.assign(partitions)
+       consumer.assign(partitions) # Optional: client handles if not used
 
    def on_revoke(consumer, partitions):
        print(f"[Classic] Revoked partitions: {partitions}")
-       consumer.unassign()
+       consumer.unassign() # Optional: client handles if not used
 
 Incremental Assignor (Including Range in Consumer / KIP-848, Any Protocol)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -214,11 +215,11 @@ Incremental Assignor (Including Range in Consumer / KIP-848, Any Protocol)
    def on_assign(consumer, partitions):
        # Only incremental partitions are passed here (not full list)
        print(f"[KIP-848] Incrementally assigning: {partitions}")
-       consumer.incremental_assign(partitions)
+       consumer.incremental_assign(partitions) # Optional: client handles if not used
 
    def on_revoke(consumer, partitions):
        print(f"[KIP-848] Incrementally revoking: {partitions}")
-       consumer.incremental_unassign(partitions)
+       consumer.incremental_unassign(partitions) # Optional: client handles if not used
 
 **Note:** The ``partitions`` list contains **only partitions being added or revoked**, not the full partition list as in the classic ``consumer.assign()``.
 
@@ -246,7 +247,7 @@ Migration Checklist (Next-Gen Protocol / `KIP-848 <https://cwiki.apache.org/conf
    broker-controlled (default: ``uniform``), valid options: ``uniform``
    or ``range``
 5. Replace deprecated configs with new ones
-6. Update rebalance callbacks to **incremental APIs only**
+6. Update rebalance callbacks to **incremental APIs only** (if used)
 7. Review static membership handling (``group.instance.id``)
 8. Ensure proper shutdown to avoid fencing issues
 9. Adjust error handling for unknown topics and authorization failures