将代理响应呈现为可视化图表

本页介绍了如何使用 Python SDK 从 Conversational Analytics API 回答提供的图表规范呈现可视化图表。示例代码从回答的 chart 字段中提取图表规范（采用 Vega-Lite 格式），并使用 Vega-Altair 库呈现图表、将其保存为图片并显示。

示例：呈现来自 API 的条形图

此示例展示了如何根据 Conversational Analytics API 代理回答呈现条形图。示例发送包含以下提示的请求：

"Create a bar graph that shows the top five states by the total number of airports."

示例代码定义了以下辅助函数：

  • render_chart_response：从 chart 消息中提取 Vega-Lite 配置、将其转换为 Vega-Altair 库可使用的格式、呈现图表、将其保存到 chart.png，并进行显示。
  • chat：使用 inline_context 变量和当前的 messages 列表向 Conversational Analytics API 发送请求，处理流式回答；如果返回图表，则调用 render_chart_response 以显示该图表。

如需使用以下示例代码，请替换以下内容：

  • sqlgen-testing：已启用必需 API 的结算项目的 ID。
  • Create a bar graph that shows the top five states by the total number of airports：您要发送给 Conversational Analytics API 的提示。
from google.cloud import geminidataanalytics
from google.protobuf.json_format import MessageToDict
import altair as alt
import proto

# Helper function for rendering chart response
def render_chart_response(resp):
  def _convert(v):
    if isinstance(v, proto.marshal.collections.maps.MapComposite):
      return {k: _convert(v) for k, v in v.items()}
    elif isinstance(v, proto.marshal.collections.RepeatedComposite):
      return [_convert(el) for el in v]
    elif isinstance(v, (int, float, str, bool)):
      return v
    else:
      return MessageToDict(v)

  vega_config = _convert(resp.result.vega_config)
  chart = alt.Chart.from_dict(vega_config)
  chart.save('chart.png')
  chart.display()

# Helper function for calling the API
def chat(q: str):
  billing_project = "sqlgen-testing"

  input_message = geminidataanalytics.Message(
      user_message=geminidataanalytics.UserMessage(text=q)
  )

  client = geminidataanalytics.DataChatServiceClient()
  request = geminidataanalytics.ChatRequest(
      inline_context=inline_context,
      parent=f"projects/{billing_project}/locations/global",
      messages=messages,
  )

  # Make the request
  stream = client.chat(request=request)

  for reply in stream:
    if "chart" in reply.system_message:
      # ChartMessage includes `query` for generating a chart and `result` with the generated chart.
      if "result" in reply.system_message.chart:
        render_chart_response(reply.system_message.chart)

# Send the prompt to make a bar graph
chat("Create a bar graph that shows the top five states by the total number of airports.")