Step 2 - Adjust Response Handling

In the conservative request example in the previous section, we called fetch to re-fetch the refreshed page after creating, editing, and deleting requests for Todo items. In order to display the results immediately after the operation, we need to make the following adjustments:

1. Set the behavior mode of create, edit and delete requests to silent, they will trigger the success callback immediately when the request is made;
2. Manually update the list, instead of pulling data, use virtual data to occupy the response data of the server;
3. Save operation records for data compensation when refreshing the page;

Set behavior mode

Set by configuring the parameter behavior, the optional parameters are queue, silent, static, or a function that returns behavior data to dynamically set the behavior mode, the default is queue.

The following sets the behavior parameters statically.

useSQRequest(createOrEditTodo, {
  behavior: 'silent',
  immediate: false
});

The following is to dynamically set the behavior parameter.

const { send } = useSQRequest(createOrEditTodo, {
  // The arg parameter can be passed in through the send function
  behavior: arg => {
    if (arg === 0) return 'silent';
    return 'queue';
  },
  immediate: false
});

When behavior is set as a function, it will be called every time a request is initiated to determine which behavior to process this request.

Silent queue description

After setting the behavior parameter to queue or silent, the request will enter the silent queue and wait for the request to be initiated. By default, they will enter the queue named default. You can also specify other queues to save silentMethod instances. without interfering with each other.

useSQRequest(createOrEditTodo, {
  // The specified request information enters the queue named queue-2
  queue: 'queue-2',
  behavior: 'silent',
  immediate: false
});

Manually update the list in the callback

Update the list after adding/editing

Page is not destroyed

When the list page is not destroyed, such as using the modal box operation on the current page, or using <keep-alive> (Vue) to keep the page components, the data will still exist. At this time, we use updateStateEffect to Update the list data. Compared with the updateState exported by alova, it has the function of tracking virtual data. When the response data is obtained, it will automatically track the virtual data in the list data and replace it with the actual data.

import { useSQRequest, updateStateEffect } from '@alova/scene-*';
import { createOrEditTodo, todoList } from './api.js';

const { onSuccess } = useSQRequest(createOrEditTodo, {
  behavior: 'silent',
  immediate: false,

  // Before processing list updates, it is necessary to construct virtual response data of the same structure according to the structure of the response data
  // For example, when creating a Todo item, the id of this piece of data will be returned.
  silentDefaultResponse: () => {
    return {
      id: '--'
    };
  }
});

onSuccess(({ data, silentMethod }) => {
  // Construct list data items
  const editingItem = {
    ...detail,

    // When editing, use the original id, otherwise use the id in the response data
    // When submitting silently, data.id is virtual data, and when in static behavior mode, data.id is the actual id value
    id: id || data.id
  };

  // use updateStateEffect instead of updateState
  updateStateEffect(todoList(), todoListRaw => {
    if (id) {
      todoListRaw = todoListRaw.map(item => (item.id === id ? editingItem : item));
    } else {
      todoListRaw.unshift(editingItem);
    }
    return todoListRaw;
  });
});

updateStateEffect is used in the same way as updateState

Page has been destroyed

When the list page has been destroyed and the data has been released, such as jumping to a new page, use setCache to update the cache data. When the list page is returned, the request will be re-initiated and the updated cache will be hit.

import { useSQRequest, setCache, equals } from '@alova/scene-*';
import { createOrEditTodo, todoList } from './api.js';

const urlParams = new URLSearchParams(window.location.search);
const id = urlParams.get('id') || '';
const { onSuccess } = useSQRequest(createOrEditTodo, {
   behavior: 'silent',
   immediate: false,

   // Before processing list updates, it is necessary to construct virtual response data of the same structure according to the structure of the response data
   // For example, when creating a Todo item, the id of this piece of data will be returned.
   silentDefaultResponse: () => {
     return {
       id: '--'
     };
   }
});
onSuccess(({ data, silentMethod }) => {
   // Construct list data items
   const editingItem = {
     ...detail,

     // When editing, use the original id, otherwise use the id in the response data
     // When submitting silently, data.id is virtual data, and when in static behavior mode, data.id is the actual id value
     id: id || data.id
   };

   const method TodoList = todoList();
   setCache(methodTodoList, todoListRaw => {
     if (id) {
       todoListRaw = todoListRaw.map(item => (equals(item.id, id) ? editingItem : item));
     } else {
       todoListRaw.unshift(editingItem);
     }
     return todoListRaw;
   });
   // Call setUpdateState to set response data tracking, so as to achieve the same delayed update effect as updateStateEffect
   if (silentMethod) {
     silentMethod.setUpdateState(methodTodoList);
     silentMethod.save();
   }
});

Update list after removal

import { useSQRequest, updateStateEffect } from '@alova/scene-*';
import { deleteTodo, todoList } from './api.js';

const { loading, data, send, onSuccess } = useSQRequest(deleteTodo, {
  immediate: false,
  behavior: 'silent'
});

onSuccess(({ sendArgs: [deletingId] }) => {
  updateStateEffect(todoList(), todoListRaw =>
    todoListRaw.filter(item => item.id !== deletingId)
  );
});

// Event callback triggers delete request
const handleDelete = deletingId => {
  send(deletingId);
};

Save the operation record

It is not enough to just update the list manually. We also need to consider that when the network is restored and there are still waiting requests in the request queue, the list data loaded at this time does not include the part of the unsubmitted request, which will cause certain problems for the user. Puzzled:

"I have clearly added multiple pieces of data, why is it not in the list?"

Therefore, we need to record the operation and related data in the success callback, so that when the list data is loaded again, the uncommitted data will be manually compensated to the list, so that the list data will always be kept up-to-date.

Saving operation records is also very simple, you only need to mount the relevant data to the silentMethod instance, and it will be persisted along with the instance.

create/edit success callback

//...
onSuccess(({ silentMethod }) => {
  // Construct list data items
  const editingItem = {
    ...detail,
    id: id || data.id
  };
  //...
  if (silentMethod) {
    // Set the name for subsequent queries
    // If editingItem.id is virtual data will be automatically converted to its id
    silentMethod.entity.setName('edit' + editingItem.id);
    silentMethod.reviewData = {
      operate: id ? 'edit' : 'add',
      data: editingItem
    };
    silentMethod.save();
  }
});

delete success callback

//...
onSuccess(({ sendArgs: [deletingId], silentMethod }) => {
  //...
  if (silentMethod) {
    silentMethod.reviewData = {
      operate: 'delete',
      data: {
        id: deletingId
      }
    };
    silentMethod.save();
  }
});

Precautions

1. In the onSuccess callback function, silentMethod has a value only in the queue and silent behavior modes;
2. Generally speaking, you can use silentMethod.a = ... or silentMethod.b = ... to save operation records, but it will report an error in typescript, so reviewData is specially provided as a silent Submit the save attribute of the operation record;
3. After modifying the silentMethod data, you need to save the modification through silentMethod.save();

The next step is to set retry parameters on silent submit requests.