From f938ef9b4b17e6d3aaf9d3688da8756f7bc7e649 Mon Sep 17 00:00:00 2001
From: kan <kan@github>
Date: Wed, 8 Dec 2021 18:42:32 +0800
Subject: [PATCH] add pagination

---
 helper.py | 101 ++++++++++++++++++++++++++++++++++++------------------
 proto.py  |  19 +++++-----
 2 files changed, 78 insertions(+), 42 deletions(-)

diff --git a/helper.py b/helper.py
index 50136d4..79c4889 100644
--- a/helper.py
+++ b/helper.py
@@ -9,6 +9,7 @@
 from PIL import Image
 
 from sqlalchemy import create_engine
+from sqlalchemy import or_
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import sessionmaker
 Base = declarative_base()
@@ -22,6 +23,7 @@
 
 DEFAULT_PRICE = 150
 INVOICE_MEMO_PREFIX = "DH Channel Explorer for channel_id: "
+DEFAULT_CHANNELCOUNT = 10
 
 def debug(message):
     sys.stderr.write(message + "\n")
@@ -53,7 +55,7 @@ def getInfo(self):
 
         return info
 
-    def getChannels(self):
+    def getChannels(self, keyword=None, channelCount=None, page=None):
         db_filename = 'sqlite:///' + os.path.join('./graph.db')
 
         engine = create_engine(db_filename, echo=True)
@@ -62,11 +64,33 @@ def getChannels(self):
         Session = sessionmaker()
         Session.configure(bind=engine)
         s = Session()
-        channels = s.query(channel.Channel).all()
+        q = s.query(channel.Channel).order_by(channel.Channel.channel_id)
+        if keyword:
+            q = q.filter(or_(channel.Channel.node2_alias.ilike(f"%{keyword}%"), channel.Channel.node2_pub == keyword))
+        if channelCount and page:
+            page = page - 1
+            sliceStart = channelCount * page
+            sliceEnd = sliceStart + channelCount
+            q = q.slice(sliceStart, sliceEnd)
+        channels = q.all()
         s.close()
 
         return channels
 
+    def getChannelTotalCount(self):
+        db_filename = 'sqlite:///' + os.path.join('./graph.db')
+
+        engine = create_engine(db_filename, echo=True)
+        Base.metadata.create_all(engine)
+
+        Session = sessionmaker()
+        Session.configure(bind=engine)
+        s = Session()
+        count = s.query(channel.Channel).count()
+        s.close()
+
+        return count
+
     #----------------------------------------------------
     #インボイス発行
     #----------------------------------------------------
@@ -148,43 +172,54 @@ def checkInvoice(self, payment_hash=""):
             resCheckInvoice = {
                     "paymentStatus": 0,
                     "lndResponse": lnd_result,
-                    #"capacity": 0,
-                    #"localBalance": 0,
-                    #"remoteBalance": 0,
                     }
             #debug
             debug("Payment Status: Not Paid")
 
         return resCheckInvoice
     
-    def search(self, keyword):
-        channels = self.getChannels()
-        if not keyword:
-            result = channels
-        else:
-            result = {}
-            j = 0
-            for i in range(len(channels)):
-                alias = channels[i].node2_alias
-                pubKey = channels[i].node2_pub
-                if keyword.lower() in alias.lower() or keyword == pubKey:
-                    result[j] = channels[i]
-                    j += 1
-
-        output = self.convertChannelsToOutput(result)
-        return output
-
-    def convertChannelsToOutput(self, channels):
+    def search(self, keyword=None, channelCount=None, page=None):
+
+        if channelCount or page:
+            if channelCount:
+                try:
+                    channelCount = int(channelCount)
+                    if channelCount < 1: raise
+                except:
+                    channelCount = DEFAULT_CHANNELCOUNT
+            else:
+                channelCount = DEFAULT_CHANNELCOUNT
+        
+            if page:
+                try:
+                    page = int(page)
+                    if page < 1: raise
+                except:
+                    page = 1
+            else:
+                page = 1
+
+        channels = self.getChannels(keyword, channelCount, page)
+        channelTotal = self.getChannelTotalCount()
         output = {}
-        for i in range(len(channels)):
-            output[i] = {
-                "channelId": str(channels[i].channel_id),
-                "alias": channels[i].node2_alias,
-                "capacity": channels[i].capacity,
-                "node1BaseFee": channels[i].node1_base_fee,
-                "node1FeeRate": channels[i].node1_fee_rate,
-                "node2PubKey": channels[i].node2_pub,
-                "node2BaseFee": channels[i].node2_base_fee,
-                "node2FeeRate": channels[i].node2_fee_rate,
+        channelsArray = []
+
+        for c in channels:
+            channelsArray.append({
+                "channelId": str(c.channel_id),
+                "alias": c.node2_alias,
+                "capacity": c.capacity,
+                "node1BaseFee": c.node1_base_fee,
+                "node1FeeRate": c.node1_fee_rate,
+                "node2PubKey": c.node2_pub,
+                "node2BaseFee": c.node2_base_fee,
+                "node2FeeRate": c.node2_fee_rate,
+                })
+        
+        output = {
+            "channelCount": channelCount,
+            "channels": channelsArray,
+            "page": page,
+            "channelTotal": channelTotal,
             }
         return output
diff --git a/proto.py b/proto.py
index adac21a..6ec1e44 100644
--- a/proto.py
+++ b/proto.py
@@ -66,22 +66,23 @@ def req_self():
 def req_channels():
     print('requesting channels...')
 
-    channels = helper.getChannels()
-    output = helper.convertChannelsToOutput(channels)
-
-    return output
+#    channels = helper.getChannels()
+#    output = helper.convertChannelsToOutput(channels)
+#    return output
+    return helper.search()
 
 # 検索機能
 # Search Functionality
 @app.route('/search')
 @app.route('/search/')
-def req_search_blank():
+#def req_search_blank():
     # Parameter Missing
-    return helper.search('')
-
+#    return helper.search('')
 @app.route('/search/<keyword>')
-def req_search(keyword):
-    return helper.search(keyword)
+def req_search(keyword=None):
+    channelCount = request.args.get('channelCount')
+    page = request.args.get('page')
+    return helper.search(keyword, channelCount, page)
 
 # インボイス発行
 # Issue invoice