AWS Pagination listObjects node.js

时间:2017-08-23 14:06:35

标签: javascript node.js amazon-web-services lambda pagination

您好我现在想要使用分页列出商店中的图像。我需要每次显示指定数量的图像,并允许循环停止在我指定的页码上。 (例如。每页30张图片,我需要第3页,我需要列出第3页图像)。到目前为止,它遍历所有文件,我只需要根据pageCount

列出objectsPerPage

(GET / list / {storeid}?page = {pageNumber}& per_page = {perPage}

var shopId = event.shopkeeper + "/";
var objectsPerPage = event.perPage;
var pageCount = event.pageNumber;

var params = {
    Bucket: AWS_Bucket,
    Delimiter: '/',
    Prefix: shopId,
    MaxKeys: objectsPerPage
}; var dataContents = [];

function s3ListObjects() {
s3.listObjects(params, function(err, data) {
    if (err) {
        console.log("listS3Objects Error:", err);
    } else {
        var contents = data.Contents;
        dataContents = dataContents.concat(contents);
        if (data.IsTruncated) {
            params.Marker = contents[contents.length-1].Key;
            s3ListObjects(params, callback);
        } else {
            console.log(dataContents);
        }
    }
});
}

1 个答案:

答案 0 :(得分:0)

我最终做的一个解决方案是创建一个pageCounter变量并将continuation tokens转换为整数值。然后,随着文件通过提供页面计数循环,这会增加。还构造了一个简单的if语句,以便当pageCount等于请求的页面时,它将console.log输出数据。

var s3DataContents = [];
var pageCounter = 0;

function s3ListObjects() {
    s3.listObjectsV2(params, function(err, data) {
    if (err) {
        console.log("listS3Objects Error:", err);
    } else {
        if(data.IsTruncated) {
            if(pageCounter == page){
                s3DataContents = data.Contents;
                s3DataContents.forEach(function(content){               
                    let dates = new Date(content.LastModified).toLocaleString();
                    let str = content.Key;
                    str = str.split(shopId).pop();
                    return console.log("name: " + str + ";" + " created: " + dates + ";" + " size: " + content.Size +  ";");
            });
            } else {
                //if more files then iterate through
                params.ContinuationToken = data.NextContinuationToken;
                s3ListObjects(params, callback); 
                //convert string into integer value
                params.ContinuationToken = parseInt(pageCounter);
                pageCounter++;
            }
        } else {
            callback("Images not found " + err);
        }
    }
});