feat: Listbuffer (for chatbotcard). #1944 #1928 (#2017)

card.go

@@ -41,6 +41,9 @@ func loadBuf(ns *Namespace, b BufD) Buf {
 	if b.M != nil {
 		return loadMapBuf(ns, b.M)
 	}
+	if b.L != nil {
+		return loadListBuf(ns, b.L)
+	}
 	return nil
 }
 

listbuf.go

@@ -0,0 +1,86 @@
+// Copyright 2020 H2O.ai, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package wave
+
+import "strconv"
+
+// ListBuf represents a list (dynamic array) buffer.
+type ListBuf struct {
+	b *FixBuf
+	i int
+}
+
+func (b *ListBuf) put(ixs any) {
+	if xs, ok := ixs.([]any); ok {
+		for _, x := range xs {
+			b.set("", x)
+		}
+	}
+}
+
+func (b *ListBuf) set(key string, v any) {
+	fb := b.b
+	// Check if key is a valid index.
+	if i, err := strconv.Atoi(key); err == nil {
+		// Support negative indices.
+		if i < 0 {
+			i += b.i
+		}
+		if i >= 0 && i < len(fb.tups) {
+			fb.seti(i, v)
+			return
+		}
+	}
+	// Otherwise, append to the current end.
+	if b.i >= len(fb.tups) {
+		xs := make([][]interface{}, len(fb.tups)*2)
+		tups := fb.tups
+		fb.tups = xs
+
+		for i, t := range tups {
+			fb.seti(i, t)
+		}
+	}
+	fb.seti(b.i, v)
+	b.i++
+}
+
+func (b *ListBuf) get(key string) (Cur, bool) {
+	// Check if key is a valid index.
+	if i, err := strconv.Atoi(key); err == nil {
+		if i < 0 {
+			i += len(b.b.tups)
+		}
+		return b.b.geti(i)
+	}
+
+	return b.b.geti(b.i)
+}
+
+func (b *ListBuf) dump() BufD {
+	return BufD{L: &ListBufD{b.b.t.f, b.b.tups, len(b.b.tups)}}
+}
+
+func loadListBuf(ns *Namespace, b *ListBufD) *ListBuf {
+	t := ns.make(b.F)
+	if len(b.D) == 0 {
+		n := b.N
+		if n <= 0 {
+			n = 10
+		}
+		return &ListBuf{newFixBuf(t, n), n - 1}
+	}
+	return &ListBuf{&FixBuf{t, b.D}, len(b.D)}
+}

protocol.go

@@ -38,6 +38,7 @@ type OpD struct {
 	C *CycBufD               `json:"c,omitempty"` // value
 	F *FixBufD               `json:"f,omitempty"` // value
 	M *MapBufD               `json:"m,omitempty"` // value
+	L *ListBufD              `json:"l,omitempty"` // value
 	D map[string]interface{} `json:"d,omitempty"` // card data
 	B []BufD                 `json:"b,omitempty"` // card buffers
 }
@@ -55,9 +56,10 @@ type CardD struct {
 
 // BufD represents the marshaled data for a buffer. This is a discriminated union.
 type BufD struct {
-	C *CycBufD `json:"c,omitempty"`
-	F *FixBufD `json:"f,omitempty"`
-	M *MapBufD `json:"m,omitempty"`
+	C *CycBufD  `json:"c,omitempty"`
+	F *FixBufD  `json:"f,omitempty"`
+	M *MapBufD  `json:"m,omitempty"`
+	L *ListBufD `json:"l,omitempty"`
 }
 
 // MapBufD represents the marshaled data for a MapBuf.
@@ -81,6 +83,12 @@ type CycBufD struct {
 	I int             `json:"i"` // index
 }
 
+type ListBufD struct {
+	F []string        `json:"f"` // fields
+	D [][]interface{} `json:"d"` // tuples
+	N int             `json:"n"` // size
+}
+
 // AppRequest represents a request from an app.
 type AppRequest struct {
 	RegisterApp   *RegisterApp   `json:"register_app,omitempty"`

py/examples/chatbot.py

@@ -1,27 +1,22 @@
 # Chatbot
-# Use this card for chat interactions.
-# #chat
+# Use this card for chatbot interactions.
+# #chatbot
 # ---
 from h2o_wave import main, app, Q, ui, data
 
 
-MAX_MESSAGES = 500
-
-
 @app('/demo')
 async def serve(q: Q):
     if not q.client.initialized:
-        # Cyclic buffer drops oldest messages when full. Must have exactly 2 columns - msg and fromUser.
-        cyclic_buffer = data(fields='msg fromUser', size=-MAX_MESSAGES)
-        q.page['example'] = ui.chatbot_card(box='1 1 5 5', data=cyclic_buffer, name='chatbot')
-        q.page['meta'] = ui.meta_card(box='', theme='h2o-dark')
+        # List buffer is a dynamic array. Cyclic buffer can also be used. Must have exactly 2 fields - msg and fromUser.
+        q.page['example'] = ui.chatbot_card(box='1 1 5 5', data=data('msg fromUser', t='list'), name='chatbot')
         q.client.initialized = True
 
     # A new message arrived.
     if q.args.chatbot:
         # Append user message.
-        q.page['example'].data[-1] = [q.args.chatbot, True]
+        q.page['example'].data += [q.args.chatbot, True]
         # Append bot response.
-        q.page['example'].data[-1] = ['I am a fake chatbot. Sorry, I cannot help you.', False]
+        q.page['example'].data += ['I am a fake chatbot. Sorry, I cannot help you.', False]
 
     await q.page.save()

py/examples/chatbot_events_stop.py

@@ -1,50 +1,48 @@
 # Chatbot
-# Use this card for chat interactions.
-# #chat
+# Use this card for chatbot interactions. Streaming can be stopped by the user.
+# #chatbot
 # ---
 from h2o_wave import main, app, Q, ui, data
 import asyncio
 
-async def stream_message(q, msg):
+
+async def stream_message(q):
     stream = ''
+    q.page['example'].data += [stream, False]
     # Show the "Stop generating" button
     q.page['example'].generating = True
-    for w in msg.split():
+    for w in 'I am a fake chatbot. Sorry, I cannot help you.'.split():
         await asyncio.sleep(0.3)
         stream += w + ' '
-        q.page['example'].data[q.client.msg_num] = [stream, False]
+        q.page['example'].data[-1] = [stream, False]
         await q.page.save()
     # Hide the "Stop generating" button
     q.page['example'].generating = False
     await q.page.save()
 
+
 @app('/demo')
 async def serve(q: Q):
     if not q.client.initialized:
-        # Use map buffer with sortable keys to store messages - allows indexing + streaming the chat messages.
-        map_buffer = data(fields='msg fromUser')
-        q.client.msg_num = 0
-        q.page['example'] = ui.chatbot_card(box='1 1 5 5', data=map_buffer, name='chatbot', events=['stop'])
-        q.page['meta'] = ui.meta_card(box='', theme='h2o-dark')
+        q.page['example'] = ui.chatbot_card(
+            box='1 1 5 5',
+            data=data(fields='msg fromUser', t='list'),
+            name='chatbot',
+            events=['stop']
+        )
         q.client.initialized = True
 
-    # Check if we get a stop event
-    if q.events.chatbot:
-        if q.events.chatbot.stop:
-            # Cancel the streaming task
-            q.client.task.cancel()
-            # Hide the "Stop generating" button
-            q.page['example'].generating = False
+    # Handle the stop event.
+    if q.events.chatbot and q.events.chatbot.stop:
+        # Cancel the streaming task.
+        q.client.task.cancel()
+        # Hide the "Stop generating" button.
+        q.page['example'].generating = False
     # A new message arrived.
     elif q.args.chatbot:
         # Append user message.
-        q.client.msg_num += 1
-        q.page['example'].data[q.client.msg_num] = [q.args.chatbot, True]
+        q.page['example'].data += [q.args.chatbot, True]
+        # Run the streaming within cancelable asyncio task.
+        q.client.task = asyncio.create_task(stream_message(q))
 
-        # Stream bot response.
-        q.client.msg_num += 1
-        chatbot_response = 'I am a fake chatbot. Sorry, I cannot help you.'
-        # Create and run a task to stream the message
-        q.client.task = asyncio.create_task(stream_message(q, chatbot_response))
-
-    await q.page.save()
+    await q.page.save()

py/examples/chatbot_stream.py

@@ -0,0 +1,30 @@
+# Chatbot
+# Use this card for chatbot interactions, supports text streaming.
+# #chatbot
+# ---
+from h2o_wave import main, app, Q, ui, data
+
+
+@app('/demo')
+async def serve(q: Q):
+    if not q.client.initialized:
+        # Use list buffer to allow easy streaming. Must have exactly 2 fields - msg and fromUser.
+        q.page['example'] = ui.chatbot_card(box='1 1 5 5', data=data(fields='msg fromUser', t='list'), name='chatbot')
+        q.client.initialized = True
+
+    # A new message arrived.
+    if q.args.chatbot:
+        # Append user message.
+        q.page['example'].data += [q.args.chatbot, True]
+        # Append bot response.
+        q.page['example'].data += ['', False]
+
+        # Stream bot response.
+        stream = ''
+        for w in 'I am a fake chatbot. Sorry, I cannot help you.'.split():
+            await q.sleep(0.1)
+            stream += w + ' '
+            q.page['example'].data[-1] = [stream, False]
+            await q.page.save()
+
+    await q.page.save()

py/examples/requirements.txt

@@ -9,6 +9,6 @@ opencv-python==4.5.5.64
 pandas==1.3.5
 plotly==5.7.0
 pygments==2.11.2
-scikit-learn==1.0.2
+scikit-learn==1.2.2
 toml==0.10.2
 vega-datasets==0.9.0

py/examples/tour.conf

@@ -32,6 +32,7 @@ layout.py
 layout_size.py
 layout_responsive.py
 chatbot.py
+chatbot_stream.py
 chatbot_events_stop.py
 form.py
 form_visibility.py