Fix SAI adapter exception due to POE PSE attribute conflicting with v…

…ariables in sai_adapter.py. (#2011)

After the recent POE PSE API update, the SAI adapter python script will fail on launch with the exception below:

byte-compiling /dash/dash-pipeline/SAI/saithrift/../rpc/usr/local/lib/python3.10/site-packages/sai_thrift/sai_adapter.py to sai_adapter.cpython-310.pyc
  File "/dash/dash-pipeline/SAI/saithrift/../rpc/usr/local/lib/python3.10/site-packages/sai_thrift/sai_adapter.py", line 37000
    global status
    ^^^^^^^^^^^^^
SyntaxError: name 'status' is parameter and global
The reason is because the POE PSE API has a attribute with name STATUS:

/**
 * @brief POE PSE attributes
 */
typedef enum _sai_poe_pse_attr_t
{
    ...

    /**
     * @brief Status of the PSE
     *
     * @type sai_poe_pse_status_t
     * @flags READ_ONLY
     */
    SAI_POE_PSE_ATTR_STATUS,

    ...
} sai_poe_pse_attr_t;
This causes the status parameter being generated in the SAI thrift adapter, and conflicting with the variable global status:

Fix

Since it is not ideal to change the API name, as it might break any code rely on it. This commit updates the template for generating the adapter code with 2 changes:

Rename the status global variable into sai_status.
Add a fallback __getattr__ function (called after no attribute is found), which ensures any existing code that gets the status variable will not break, such as adapter.status.


Signed-off-by: r12f <r12f.code@gmail.com>

meta/templates/sai_adapter.py.tt

@@ -22,7 +22,7 @@
         [%- ELSIF function.operation == 'stats' %]
         Dict[str, [% function.rpc_return.type.subtype.python_name %]]: stats
         [%- ELSIF function.rpc_return.type.name == 'void' AND NOT function.rpc_return.is_list %]
-        status: the error code
+        sai_status: the error code
 	[%- ELSE %]
         [% function.rpc_return.type.python_name %]: [% function.rpc_return.name %]
 	[%- END -%]
@@ -34,7 +34,7 @@
         [%- ELSIF function.rpc_return.type.name == 'void' AND NOT function.rpc_return.is_list %]
 
     Returns:
-        status: the error code
+        sai_status: the error code
 	[%- END -%]
     [%- END %]
 
@@ -190,10 +190,10 @@ client.[% function.thrift_name %](
 
 [%- BLOCK catch_exception -%]
     except sai_thrift_exception as e:
-        status = e.status
-        if SKIP_TEST_ON_EXPECTED_ERROR and status in EXPECTED_ERROR_CODE:
+        sai_status = e.status
+        if SKIP_TEST_ON_EXPECTED_ERROR and sai_status in EXPECTED_ERROR_CODE:
             reason = "SkipTest on expected error. [% function.thrift_name %] with errorcode: {} error: {}".format(
-                status, e)
+                sai_status, e)
             print(reason)
             testutils.skipped_test_count=1
             raise SkipTest(reason)
@@ -207,7 +207,7 @@ client.[% function.thrift_name %](
     [%- ELSIF function.operation == 'create' %]
             pass
     [%- ELSE %]
-            return status
+            return sai_status
     [%- END %]
         else:
             raise e
@@ -275,8 +275,8 @@ client.[% function.thrift_name %](
     [%- # For 'set attr' function we just do call the funtion for first argument -%]
     [%- IF function.operation == 'set' -%]
 
-    global status
-    status = SAI_STATUS_SUCCESS
+    global sai_status
+    sai_status = SAI_STATUS_SUCCESS
 
 
         [%- WRAPPER try -%]
@@ -413,11 +413,11 @@ client.[% function.thrift_name %](
 [%- ######################################################################## -%]
 
 [%- BLOCK return_from_empty_function -%]
-    global status
-    status = SAI_STATUS_NOT_SUPPORTED
-    if SKIP_TEST_ON_EXPECTED_ERROR and status in EXPECTED_ERROR_CODE:
+    global sai_status
+    sai_status = SAI_STATUS_NOT_SUPPORTED
+    if SKIP_TEST_ON_EXPECTED_ERROR and sai_status in EXPECTED_ERROR_CODE:
         reason = "SkipTest on expected error. [% function.name %] with errorcode: {} error: {}".format(
-            status, e)
+            sai_status, e)
         print(reason)
         testutils.skipped_test_count=1
         raise SkipTest(reason)
@@ -426,12 +426,12 @@ client.[% function.thrift_name %](
     [%- IF function.operation == 'create' AND NOT function.rpc_return.is_list %]
         return SAI_NULL_OBJECT_ID
     [%- ELSIF function.operation != 'get' AND function.operation != 'stats' AND function.rpc_return.type.name == 'void' %]
-        return status
+        return sai_status
     [%- ELSE %]
         return None
     [%- END %]
     else:
-        raise sai_thrift_exception(status)
+        raise sai_thrift_exception(sai_status)
 [%- END -%]
 
 [%- ######################################################################## -%]
@@ -454,8 +454,8 @@ client.[% function.thrift_name %](
         [%- # Now, call the thrift function -%]
         [%- IF function.operation != 'set' -%]
 
-    global status
-    status = SAI_STATUS_SUCCESS
+    global sai_status
+    sai_status = SAI_STATUS_SUCCESS
 
 
             [%- WRAPPER try -%] 
@@ -468,7 +468,7 @@ client.[% function.thrift_name %](
 
         [%- # Return a status only if a function does not, and does not return something else -%]
         [%- IF function.operation != 'get' AND function.operation != 'stats' AND function.rpc_return.type.name == 'void' %]
-    return status
+    return sai_status
 
         [%- END -%]
 
@@ -523,7 +523,14 @@ CATCH_EXCEPTIONS = True
 EXPECTED_ERROR_CODE = [-2]
 # Skip test when hitting an expected error
 SKIP_TEST_ON_EXPECTED_ERROR = True
-status = 0
+sai_status = 0
+
+def __getattr__(name):
+    if name == 'status':
+        global sai_status
+        return sai_status
+    else:
+        raise AttributeError(f'module {__name__} has no attribute {name}')
 
 [%- PROCESS dev_utils IF dev_utils -%]
 [%- PROCESS invocation_logger IF adapter_logger -%]