From 11b5a6d8f023accaadbafe02544f49aa76361401 Mon Sep 17 00:00:00 2001
From: RamiNoodle733 <rami@example.com>
Date: Thu, 5 Feb 2026 22:20:40 -0600
Subject: [PATCH] fix: Truncate large table samples in Teams alerts to prevent
 payload size issues (#2044)

When sending alerts to Microsoft Teams with large test result samples
(>25 rows with multiple columns), the payload exceeds Teams' limits
and gets rejected. This fix adds:

- New maximum_rows_in_alert_samples_table config parameter (default: 25)
- Table truncation logic that limits rows and adds a message about omitted rows
- CLI option --maximum-rows-in-alert-samples-table (-mr) to customize the limit

Fixes #2044
---
 elementary/config/config.py                   |  7 ++++++
 .../monitor/alerts/alert_messages/builder.py  | 24 ++++++++++++++++---
 elementary/monitor/cli.py                     |  9 +++++++
 .../alerts/data_monitoring_alerts.py          |  3 ++-
 4 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/elementary/config/config.py b/elementary/config/config.py
index b8e56143c..9eed42abf 100644
--- a/elementary/config/config.py
+++ b/elementary/config/config.py
@@ -72,6 +72,7 @@ def __init__(
         report_url: Optional[str] = None,
         teams_webhook: Optional[str] = None,
         maximum_columns_in_alert_samples: Optional[int] = None,
+        maximum_rows_in_alert_samples_table: Optional[int] = None,
         env: str = DEFAULT_ENV,
         run_dbt_deps_if_needed: Optional[bool] = None,
         project_name: Optional[str] = None,
@@ -112,6 +113,12 @@ def __init__(
             4,
         )
 
+        self.maximum_rows_in_alert_samples_table = self._first_not_none(
+            maximum_rows_in_alert_samples_table,
+            config.get("maximum_rows_in_alert_samples_table"),
+            25,
+        )
+
         self.timezone = self._first_not_none(
             timezone,
             config.get("timezone"),
diff --git a/elementary/monitor/alerts/alert_messages/builder.py b/elementary/monitor/alerts/alert_messages/builder.py
index 593b9ff38..29fc5ecb1 100644
--- a/elementary/monitor/alerts/alert_messages/builder.py
+++ b/elementary/monitor/alerts/alert_messages/builder.py
@@ -63,6 +63,7 @@
 class MessageBuilderConfig(BaseModel):
     alert_groups_subscribers: bool = False
     maximum_columns_in_alert_samples: int = 4
+    maximum_rows_in_alert_samples_table: int = 25
 
 
 class AlertMessageBuilder:
@@ -394,9 +395,26 @@ def _get_result_blocks(
                     and len(result_sample[0].keys())
                     <= self.config.maximum_columns_in_alert_samples
                 ):
-                    result_blocks.append(
-                        TableBlock.from_dicts(result_sample),
-                    )
+                    # Truncate table if too many rows to prevent Teams payload size issues
+                    if len(result_sample) > self.config.maximum_rows_in_alert_samples_table:
+                        truncated_sample = result_sample[:self.config.maximum_rows_in_alert_samples_table]
+                        omitted_rows_count = len(result_sample) - self.config.maximum_rows_in_alert_samples_table
+                        result_blocks.append(
+                            TableBlock.from_dicts(truncated_sample),
+                        )
+                        result_blocks.append(
+                            LinesBlock(
+                                lines=[
+                                    ItalicTextLineBlock(
+                                        text=f"... and {omitted_rows_count} more rows (truncated to prevent payload size issues)"
+                                    ),
+                                ]
+                            )
+                        )
+                    else:
+                        result_blocks.append(
+                            TableBlock.from_dicts(result_sample),
+                        )
                 else:
                     result_blocks.append(
                         JsonCodeBlock(content=result_sample),
diff --git a/elementary/monitor/cli.py b/elementary/monitor/cli.py
index 9b47133ff..a4ee0280d 100644
--- a/elementary/monitor/cli.py
+++ b/elementary/monitor/cli.py
@@ -298,6 +298,13 @@ def get_cli_properties() -> dict:
     default=4,
     help="Maximum number of columns to display as a table in alert samples. Above this, the output is shown as raw JSON.",
 )
+@click.option(
+    "--maximum-rows-in-alert-samples-table",
+    "-mr",
+    type=int,
+    default=25,
+    help="Maximum number of rows to display in a table in alert samples. Above this, the table will be truncated to prevent Teams payload size issues.",
+)
 @click.pass_context
 def monitor(
     ctx,
@@ -330,6 +337,7 @@ def monitor(
     excludes,
     teams_webhook,
     maximum_columns_in_alert_samples,
+    maximum_rows_in_alert_samples_table,
     quiet_logs,
 ):
     """
@@ -364,6 +372,7 @@ def monitor(
         report_url=report_url,
         teams_webhook=teams_webhook,
         maximum_columns_in_alert_samples=maximum_columns_in_alert_samples,
+        maximum_rows_in_alert_samples_table=maximum_rows_in_alert_samples_table,
         quiet_logs=quiet_logs,
     )
     anonymous_tracking = AnonymousCommandLineTracking(config)
diff --git a/elementary/monitor/data_monitoring/alerts/data_monitoring_alerts.py b/elementary/monitor/data_monitoring/alerts/data_monitoring_alerts.py
index 8b24e3be2..30d1d1a6a 100644
--- a/elementary/monitor/data_monitoring/alerts/data_monitoring_alerts.py
+++ b/elementary/monitor/data_monitoring/alerts/data_monitoring_alerts.py
@@ -129,7 +129,8 @@ def __init__(
         self.alerts_integration = self._get_integration_client()
         self.alert_message_builder = AlertMessageBuilder(
             MessageBuilderConfig(
-                maximum_columns_in_alert_samples=self.config.maximum_columns_in_alert_samples
+                maximum_columns_in_alert_samples=self.config.maximum_columns_in_alert_samples,
+                maximum_rows_in_alert_samples_table=self.config.maximum_rows_in_alert_samples_table,
             )
         )