Create earthquake_fetcher.py

src/earthquake_fetcher.py

@@ -0,0 +1,52 @@
+import streamlit as st
+from obspy.clients.fdsn import Client
+from obspy import UTCDateTime
+
+# 使用快取來避免重複向IRIS請求相同時間範圍的資料
+@st.cache_data(ttl=600)  # 快取10分鐘
+def get_earthquake_data(start_time, end_time, network="TW", station="*", channel="BHZ,HHZ"):
+    """
+    從 IRIS FDSN 服務獲取地震波形和測站元數據。
+    
+    Args:
+        start_time (UTCDateTime): 查詢開始時間
+        end_time (UTCDateTime): 查詢結束時間
+        network (str): 測站網絡代碼
+        station (str): 測站代碼
+        channel (str): 頻道代碼
+        
+    Returns:
+        tuple: (Stream, Inventory) or (None, None) if no data
+    """
+    client = Client("IRIS")
+    try:
+        st.write(f"正在從 IRIS 獲取 {network} 測站網的資料...")
+        stream = client.get_waveforms(
+            network=network,
+            station=station,
+            location="*",
+            channel=channel,
+            starttime=start_time,
+            endtime=end_time,
+        )
+        
+        st.write("正在獲取測站座標...")
+        inventory = client.get_stations(
+            network=network,
+            station=station,
+            location="*",
+            channel=channel,
+            starttime=start_time,
+            endtime=end_time,
+            level="station"
+        )
+        
+        if not stream:
+            st.warning("在指定時間範圍內未找到任何波形資料。")
+            return None, None
+            
+        return stream, inventory
+        
+    except Exception as e:
+        st.error(f"資料獲取失敗: {e}")
+        return None, None