From 85fd92bba5af2dcc4a382d2dc4908be9308dfff6 Mon Sep 17 00:00:00 2001
From: Mika <kontakt@donau2space.de>
Date: Fri, 13 Mar 2026 16:23:00 +0000
Subject: [PATCH] Add outlier_analysis/src/outlier_analysis/core.py

---
 outlier_analysis/src/outlier_analysis/core.py | 76 +++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 outlier_analysis/src/outlier_analysis/core.py

diff --git a/outlier_analysis/src/outlier_analysis/core.py b/outlier_analysis/src/outlier_analysis/core.py
new file mode 100644
index 0000000..3baddef
--- /dev/null
+++ b/outlier_analysis/src/outlier_analysis/core.py
@@ -0,0 +1,76 @@
+from __future__ import annotations
+import json
+import statistics
+from pathlib import Path
+from typing import List, Dict, Any
+import pandas as pd
+
+
+class InputValidationError(ValueError):
+    """Raised when input validation fails for log entries."""
+    pass
+
+
+def _validate_log_entries(log_entries: List[Dict[str, Any]]) -> None:
+    if not isinstance(log_entries, list):
+        raise InputValidationError("log_entries must be a list of dicts.")
+    for entry in log_entries:
+        if not isinstance(entry, dict):
+            raise InputValidationError("Each log entry must be a dict.")
+        required_fields = [
+            "corr_id",
+            "stratum",
+            "retry_total_overhead_ms",
+        ]
+        for field in required_fields:
+            if field not in entry:
+                raise InputValidationError(f"Missing required field '{field}' in log entry.")
+
+
+def analyze_outliers(log_entries: List[Dict[str, Any]]) -> Dict[str, Any]:
+    """Analysiert Log-Einträge und erstellt statistische Kennzahlen zu Outliern.
+
+    Args:
+        log_entries (List[Dict[str, Any]]): Liste von Log-Einträgen.
+
+    Returns:
+        Dict[str, Any]: Statistik- und Clusterinformationen im JSON-kompatiblen Format.
+    """
+    _validate_log_entries(log_entries)
+    
+    df = pd.DataFrame(log_entries)
+    if df.empty or 'retry_total_overhead_ms' not in df.columns:
+        raise InputValidationError("No retry_total_overhead_ms data found.")
+
+    values = df['retry_total_overhead_ms'].dropna().astype(float).tolist()
+    if not values:
+        raise InputValidationError("No valid numerical values for retry_total_overhead_ms.")
+
+    report: Dict[str, Any] = {
+        "mean": float(statistics.fmean(values)),
+        "median": float(statistics.median(values)),
+        "p90": float(df['retry_total_overhead_ms'].quantile(0.90)),
+        "p95": float(df['retry_total_overhead_ms'].quantile(0.95)),
+        "p99": float(df['retry_total_overhead_ms'].quantile(0.99)),
+        "max": float(df['retry_total_overhead_ms'].max()),
+        "clusters": [],
+    }
+
+    high_threshold = report["p95"]
+    clusters = []
+    high_outliers = df[df['retry_total_overhead_ms'] >= high_threshold]
+    if not high_outliers.empty:
+        grouped = high_outliers.groupby('stratum')
+        for name, group in grouped:
+            clusters.append({
+                "stratum": name,
+                "count": int(len(group)),
+                "mean_overhead": float(group['retry_total_overhead_ms'].mean()),
+                "max_overhead": float(group['retry_total_overhead_ms'].max()),
+            })
+    report["clusters"] = clusters
+
+    # CI assertions for data integrity
+    assert set(report.keys()) == {"mean", "median", "p90", "p95", "p99", "max", "clusters"}, "Unexpected report format"
+
+    return report