javascript - AWS Pagination listObjects node.js

Question

您好，我目前想使用分页列出商店内的图像。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 个图像，我需要第 3 页，我需要列出第 3 页的图像)。到目前为止，它遍历了所有文件，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);
        }
    }
});
}

Answer 1

我最终采取的解决方案是创建一个 pageCounter 变量并将延续标记转换为整数值。然后，随着文件循环提供页数，该值会增加。还构建了一个简单的 if 语句，以便当 pageCount 等于请求的页面时，它将 console.log 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);
        }
    }
});