DataFlex

S3 List Objects in Bucket Folder

See more Amazon S3 Examples

Demonstrates how to retrieve the XML listing of the objects (i.e. files) stored in an Amazon S3 bucket, but just within a particular folder. DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoHttp
    String sStrXml
    Handle hoXml
    Integer iNumItems
    String sItemKey
    String sItemSizeDecimalStr
    String sLastModTimestamp
    Handle hoDt
Obj    Handle hoDtObj
    Integer i
    Boolean iBLocal
    String sTemp1
    Integer iTemp1
    Integer iTemp2
    Integer iTemp3
    Integer iTemp4
    Integer iTemp5
    Boolean bTemp1

    Move False To iSuccess

    // This example assumes the Chilkat HTTP API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // In Amazon S3 (Simple Storage Service), there is a distinction between buckets and folders,
    // which are both used for organizing and storing data.

    // Bucket: A bucket is the top-level container in Amazon S3. It is similar to a directory or folder
    // at the root level and acts as a unique namespace for your objects (files). Each bucket must have a globally
    // unique name across all of Amazon S3. Buckets are created at the AWS account level and are used to store objects.

    // Folder (Prefix): In Amazon S3, folders are not actual physical entities but are virtual constructs called prefixes.
    // They are part of the object keys used to organize and group objects within a bucket. Object keys are essentially the
    // full path or name of an object, including the folder structure. For example, if you have an object named
    // "my-image.jpg" inside a folder named "photos," the object key would be "photos/my-image.jpg."
    // Folders are helpful for organizing objects within a bucket and creating a hierarchical structure.

    // In reality, S3 does not have a true folder structure. It stores objects in a flat structure with unique keys.
    // However, the keys can include slashes ("/") to create a visual separation that resembles a folder structure.
    // Various tools and S3 clients interpret the slashes as folder separators and display them accordingly.

    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End

    // Insert your access key here:
    Set ComAwsAccessKey Of hoHttp To "AWS_ACCESS_KEY"

    // Insert your secret key here:
    Set ComAwsSecretKey Of hoHttp To "AWS_SECRET_KEY"

    // ----------------------------------------------------------------------------------
    // List the objects having prefix "images/"
    // ----------------------------------------------------------------------------------
    Get ComS3_ListBucketObjects Of hoHttp "chilkat100?prefix=images/" To sStrXml
    Get ComLastMethodSuccess Of hoHttp To bTemp1
    If (bTemp1 = False) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComLastStatus Of hoHttp To iTemp1
    Showln "Response status code = " iTemp1

    Get Create (RefClass(cComChilkatXml)) To hoXml
    If (Not(IsComObjectCreated(hoXml))) Begin
        Send CreateComObject of hoXml
    End
    Get ComLoadXml Of hoXml sStrXml To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoXml To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // If the response status code was not 200, then the XML response is not a 
    // listing of objects, but instead contains error information.
    Get ComLastStatus Of hoHttp To iTemp1
    If (iTemp1 <> 200) Begin
        Get ComGetXml Of hoXml To sTemp1
        Showln sTemp1
        Showln "Failed."
        Procedure_Return
    End

    // A sample response is shown below.
    Get ComGetXml Of hoXml To sTemp1
    Showln sTemp1
    Showln "----"

    // Use this online tool to generate parsing code from sample XML: 
    // Generate Parsing Code from XML

    // Iterate over the bucket items and get information for each..
    Get ComNumChildrenHavingTag Of hoXml "Contents" To iNumItems
    Showln "Number of bucket items = " iNumItems

    Get Create (RefClass(cComCkDateTime)) To hoDt
    If (Not(IsComObjectCreated(hoDt))) Begin
        Send CreateComObject of hoDt
    End
    Get Create (RefClass(cComChilkatDtObj)) To hoDtObj
    If (Not(IsComObjectCreated(hoDtObj))) Begin
        Send CreateComObject of hoDtObj
    End

    Move 0 To i
    While (i < iNumItems)
        Set ComI Of hoXml To i

        Get ComGetChildContent Of hoXml "Contents[i]|Key" To sItemKey
        Get ComGetChildContent Of hoXml "Contents[i]|Size" To sItemSizeDecimalStr
        Get ComGetChildContent Of hoXml "Contents[i]|LastModified" To sLastModTimestamp

        Get ComSetFromRfc822 Of hoDt sLastModTimestamp To iSuccess
        // Get a local date/time.
        Move True To iBLocal
        Get pvComObject of hoDtObj to vDtObj
        Send ComToDtObj To hoDt iBLocal vDtObj

        Get ComDay Of hoDtObj To iTemp1
        Get ComMonth Of hoDtObj To iTemp2
        Get ComYear Of hoDtObj To iTemp3
        Get ComHour Of hoDtObj To iTemp4
        Get ComMinute Of hoDtObj To iTemp5
        Showln i ": " sItemKey ", " sItemSizeDecimalStr ", " iTemp1 "-" iTemp2 "-" iTemp3 ":" iTemp4 ":" iTemp5

        Move (i + 1) To i
    Loop

    // Sample output from the above loop:

    // 0: images/africa/, 0, 11-6-2020:20:18
    // 1: images/africa/giraffe.jpg, 262769, 11-6-2020:20:20
    // 2: images/africa/lion.jpg, 1026769, 11-6-2020:20:20
    // 3: images/sea_creatures/starfish123.jpg, 6229, 19-1-2017:10:45
    // 4: images/sea_creatures/starfish���.jpg, 6229, 19-1-2017:12:7


End_Procedure