glm-4模型，开启stream，返回值会有截断不完整

General
1

在nodejs环境下，使用axios发送post请求，在stream开启情况下，每次返回的内容最后一条不完整，必须要和之后第一条数据做合并。第一次使用stream的方式返回数据，不知道这种情况是正常的，还是bug。
这是代码：

async function mainStream() {
  const response = await axios({
    method: 'post',
    url: 'https://open.bigmodel.cn/api/paas/v4/chat/completions',
    data: {
      model: 'glm-4',
      messages: [
        {
          role: "user",
          content: "介绍一下山西"
        }
      ],
      stream: true
    },
    headers: {
      Authorization: token
    },
    responseType: 'stream',
  })

  let str = ''

  let errStr = ''

  response.data.on('data', (chunk) => {
    const msg = chunk.toString('utf8');
    console.log('---- $$$ ---');
    console.log(msg);
    const allMessages = chunk.toString('utf8').split("\n\n");
    for (let index = 0; index < allMessages.length; index++) {
      const element = allMessages[index];
      let data = element.substring(6);

      if (data === '[DONE]') {
        break
      }
      try {
        data = JSON.parse(data)
        str += data.choices[0].delta.content
        // console.log(str);
      } catch (error) {
        if (index === 0) {
          errStr += element
          let data1 = errStr.substring(6);
          data1 = JSON.parse(data1)
          const errData = data1.choices[0].delta.content
          str += errData
          // console.log(str);
          errStr = ''
        }
        if (index + 1 === allMessages.length) {
          errStr = element
        }
      }
    }
  })

  response.data.on('end', (chunk) => {
    console.log(str);
    console.log('返回完成');
  })
}

这是现象：

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"的"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"de
---- $$$ ---
lta":{"role":"assistant","content":"游客"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"应"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"提前"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"查询"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"最新的"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"限"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"行"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"a
---- $$$ ---
ssistant","content":"政策"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"。\n\n总的来说"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"，"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"山西"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"是一个"}}]}

data: {"id":"8356085236399216072","created":1706939757,"model":"glm-4","choices":[{"index":0,"delta":{"role":"assistant","content":"自然"}}]}