简体   繁体   中英

AWS Pagination listObjects node.js

Hi I am currently wanting to list images within a store with the use of pagination. I need to display a specified number of images each time and allow the loop to stop on the page number i have specified. (example. 30 images per page and I need page 3 I will need to list the 3rd page of images). So far it iterates through all the files, I just need to list objectsPerPage depending on the pageCount

(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);
        }
    }
});
}

A solution that I eventually did was create a pageCounter variable and converted the continuation tokens into integer values. This then incremented as the files are looped through providing a page count. A simple if statement is also constructed so that when the pageCount is equal to the page requested it will console.log out the data.

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);
        }
    }
});

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM