ianmcook commented on code in PR #39081:
URL: https://github.com/apache/arrow/pull/39081#discussion_r1416584067


##########
http/examples/get/server.py:
##########
@@ -0,0 +1,75 @@
+import pyarrow as pa
+from random import randbytes
+from http.server import BaseHTTPRequestHandler, HTTPServer
+
+schema = pa.schema([
+    ('a', pa.int64()),
+    ('b', pa.int64()),
+    ('c', pa.int64()),
+    ('d', pa.int64())
+])
+
+def GetPutData():
+    total_records = 100000000
+    length = 4096
+    ncolumns = 4
+    
+    arrays = []
+    
+    for x in range(0, ncolumns):
+        buffer = pa.py_buffer(randbytes(length * 8))
+        arrays.append(pa.Int64Array.from_buffers(pa.int64(), length, [None, 
buffer], null_count=0))
+    
+    batch = pa.record_batch(arrays, schema)
+    batches = []
+    
+    records_sent = 0
+    while records_sent < total_records:
+      if records_sent + length > total_records:
+        last_length = total_records - records_sent
+        batches.append(batch.slice(0, last_length))
+        records_sent += last_length
+      else:
+        batches.append(batch)
+        records_sent += length
+    
+    return batches
+ 
+class MyServer(BaseHTTPRequestHandler):
+    def do_GET(self):
+        chunk_size = int(2e9)
+        chunk_splits = len(buffer) // chunk_size
+        
+        self.send_response(200)
+        self.send_header('Content-Type', 'application/vnd.apache.arrow.stream')
+        
+        #######################################################################
+        # include these to enable testing JavaScript client in local browser
+        self.send_header('Access-Control-Allow-Origin', 
'http://localhost:8080')
+        self.send_header('Access-Control-Allow-Methods', 'GET')
+        self.send_header('Access-Control-Allow-Headers', 'Content-Type')
+        #######################################################################
+        
+        self.end_headers()
+        
+        for i in range(chunk_splits):
+            self.wfile.write(buffer.slice(i * chunk_size, chunk_size))
+            self.wfile.flush()
+        self.wfile.write(buffer.slice(chunk_splits * chunk_size))
+        self.wfile.flush()
+
+batches = GetPutData()
+
+sink = pa.BufferOutputStream()
+
+with pa.ipc.new_stream(sink, schema) as writer:
+   for i in range(len(batches)):
+      writer.write_batch(batches[i])
+
+buffer = sink.getvalue()

Review Comment:
   I added `server_low_mem.py` which is the same as `server.py` but uses this 
trick.



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