Windows Azure Node.js SDK

Question

我想知道如何使用 Windows Azure Node.js SDK 获取延续 token ？例如，我现在使用 SDK 来从表中检索数据:

var tableService = azure.createTableService();

tableService.getTable('UsersUserFacebookActions', function (error) {
    if (error === null) {
        var query = azure.TableQuery
            .select()
            .from('UsersUserFacebookActions')
            .where('PartitionKey eq ?', userID)
            .and('Kind eq ?', 'User')
            .and('Deleted eq ?', 'false');

        tableService.queryEntities(query, function (error, userEntities) {
            if (error === null && userEntities.length > 0) {
                // check to see if access token needs extending
                extendAccessToken(userEntities[0], function (user) {
                    callback({
                        PartitionKey: user.PartitionKey,
                        RowKey: user.RowKey,
                        Kind: user.Kind,
                        EmailAddress: user.EmailAddress,
                        AccessToken: user.AccessToken,
                        TokenExpiration: user.TokenExpiration,
                        JoinDate: user.JoinDate,
                        ChannelCount: user.ChannelCount,
                        FollowCount: user.FollowCount,
                        ChannelCountString: accounting.formatNumber(user.ChannelCount),
                        FollowCountString: accounting.formatNumber(user.FollowCount),
                        Deleted: user.Deleted,
                        DeleteDate: user.DeleteDate
                    }); 
                });
            }
            else callback();
        });
    }
    else callback();
});

但是，我已经搜索了示例和文档，包括此站点:

https://www.windowsazure.com/en-us/develop/nodejs/

但没有遇到任何提及延续 token 的内容。

如有任何帮助或建议，我们将不胜感激。

Answer 1

根据源代码(第 481 行)，如果存在继续标记，则“queryEntitiesResultContinuation”属性将添加到您的结果中:

https://github.com/WindowsAzure/azure-sdk-for-node/blob/master/lib/services/table/tableservice.js

它有一个名为“getNextPage”的函数，它需要回调:

https://github.com/WindowsAzure/azure-sdk-for-node/blob/master/lib/services/table/models/queryentitiesresultcontinuation.js

您可能应该创建一个单独的函数来处理查询结果。此函数将迭代实体，然后检查是否设置了“queryEntitiesResultContinuation”。如果是这样，请调用该函数，并将新函数作为回调传递。

我还没有实际尝试过，也找不到任何代码示例!

更新

以下是使用 Node 处理延续标记的代码示例:

var tableService = require("azure").createTableService();

function queryWithContinuation(query, cb) {
    tableService.queryEntities(query, function(error, entities, continuationToken){
        if (continuationToken.nextPartitionKey) { 
            nextPage(entities, continuationToken, cb);
        } else {
            cb(entities);                    
        }
    });
}

// used to recursively retrieve the results
function nextPage(entities, continuationToken, cb){
    continuationToken.getNextPage(function(error, results, newContinuationToken){
        entities = entities.concat(results);
        if (newContinuationToken.nextPartitionKey){
            nextPage(entities, newContinuationToken, cb);
        } else {
            cb(entities);
        }
    });
}

// example usage
var query = azure.TableQuery.select().from('really-big-table');
queryWithContinuation(query, function(results){
    console.log(results);
});