Skip to main content

Get Object

Retrieves metadata information about an S3 object without downloading the actual file content.

Common Properties​

  • Name - The custom name of the node.
  • Color - The custom color of the node.
  • Delay Before (sec) - Waits in seconds before executing the node.
  • Delay After (sec) - Waits in seconds after executing node.
  • Continue On Error - Automation will continue regardless of any error. The default value is false.
info

If the ContinueOnError property is true, no error is caught when the project is executed, even if a Catch node is used.

Inputs​

  • Client Id - The client connection ID from the Connect node. Optional if using credentials directly.
  • Bucket Name - The name of the S3 bucket containing the object.
  • Object Name - The key/name of the object to get information about, including any prefixes (folder path).

Options​

  • End Point - S3 endpoint URL. Required only if using credentials directly instead of Client ID.
  • Access Key Id - AWS Access Key ID credential. Optional - use this instead of Client ID for direct authentication.
  • Secret Key Access - AWS Secret Access Key credential. Optional - use this instead of Client ID for direct authentication.

Output​

  • result - An object containing metadata about the S3 object, including size, content type, last modified date, ETag, and user metadata.

How It Works​

The Get Object node retrieves detailed information about an S3 object without downloading the file content. When executed, the node:

  1. Retrieves the S3 client using either the Client ID or creates a new client from credentials
  2. Validates that the bucket name and object name are provided and not empty
  3. Sends a HEAD request to S3 to retrieve object metadata
  4. Returns the metadata information as the result
  5. Completes successfully without downloading the file content

Requirements​

  • Either a valid Client ID from a Connect node, or Access Key ID and Secret Access Key credentials
  • A valid S3 bucket with the object to query
  • Appropriate S3 permissions to read object metadata (s3:GetObject)

Error Handling​

The node will return specific errors in the following cases:

  • Empty or invalid bucket name
  • Empty or invalid object name
  • Object does not exist in the bucket
  • Invalid Client ID or credentials
  • Bucket does not exist
  • Insufficient permissions to access object metadata
  • Network or connection errors

Output Structure​

The result object contains the following information:

{
  "Key": "documents/report.pdf",
  "Size": 1048576,
  "ContentType": "application/pdf",
  "LastModified": "2024-03-15T10:30:00Z",
  "ETag": "\"d41d8cd98f00b204e9800998ecf8427e\"",
  "StorageClass": "STANDARD",
  "Metadata": {
    "uploaded-by": "automation-bot",
    "document-type": "report"
  },
  "VersionID": ""
}

Metadata Fields​

  • Key - The object's key (name) in S3
  • Size - Size of the object in bytes
  • ContentType - MIME type of the object
  • LastModified - Timestamp when the object was last modified
  • ETag - Entity tag (checksum) of the object
  • StorageClass - The storage class (STANDARD, GLACIER, etc.)
  • Metadata - Custom user metadata attached to the object
  • VersionID - Version ID if bucket versioning is enabled

Usage Notes​

  • This operation is much faster than downloading the file
  • No data transfer costs are incurred (only metadata retrieval)
  • Useful for checking if an object exists before downloading
  • ETag can be used to verify file integrity
  • Size information helps with disk space planning
  • LastModified helps with synchronization logic
  • Custom metadata is returned in the Metadata field

Best Practices​

  • Use Get Object to verify object existence before download
  • Check object size before downloading to ensure sufficient disk space
  • Use ETag to detect if an object has changed
  • Leverage LastModified for incremental sync operations
  • Validate content type matches expectations before processing
  • Cache metadata when processing multiple objects
  • Use this node instead of downloading when you only need metadata

Example​

To get information about a PDF document:

Inputs:

  • Client Id: (from Connect node)
  • Bucket Name: company-documents
  • Object Name: reports/annual-report-2024.pdf

Output:

{
  "Key": "reports/annual-report-2024.pdf",
  "Size": 2457600,
  "ContentType": "application/pdf",
  "LastModified": "2024-03-15T14:30:00Z",
  "ETag": "\"5f363e0e58a95f06cbe9bbc662c5dfb6\"",
  "StorageClass": "STANDARD",
  "Metadata": {
    "year": "2024",
    "department": "finance",
    "status": "approved"
  }
}

Common Use Cases​

File Existence Check Verify an object exists before attempting to download or process it:

  1. Get Object - Check if file exists
  2. Conditional - If exists, proceed with download
  3. Download Object - Download the file

Size Validation Check file size before downloading to ensure sufficient disk space:

const metadata = result; // Output from Get Object
const fileSizeInMB = metadata.Size / 1024 / 1024;

if (fileSizeInMB > 100) {
  // Handle large file differently
}

Change Detection Compare ETag or LastModified to detect if a file has changed:

// Store previous ETag
const previousETag = "\"abc123...\"";
const currentETag = result.ETag;

if (currentETag !== previousETag) {
  // File has changed, download new version
}

Incremental Sync Download only files that have been modified since last sync:

const lastSyncTime = new Date('2024-03-01T00:00:00Z');
const objectModified = new Date(result.LastModified);

if (objectModified > lastSyncTime) {
  // Download updated file
}

Storage Cost Analysis Calculate storage costs based on object size and storage class:

const sizeInGB = result.Size / (1024 * 1024 * 1024);
const storageClass = result.StorageClass;
// Calculate costs based on AWS pricing

Direct Credentials Example​

Inputs:

  • Bucket Name: my-data
  • Object Name: exports/data-2024-03.csv

Options:

  • End Point: s3.us-west-2.amazonaws.com
  • Access Key Id: (your AWS Access Key ID credential)
  • Secret Key Access: (your AWS Secret Access Key credential)

Working with Metadata​

Access custom metadata from the result:

const metadata = result.Metadata;
const uploadedBy = metadata['uploaded-by'];
const documentType = metadata['document-type'];

Note: S3 stores user metadata with the x-amz-meta- prefix, but this is stripped in the response.

Conditional Download Example​

Download only if file is newer than local version:

  1. Get Object - Get S3 object metadata
  2. Get Local File Info - Get local file modification time
  3. Compare Dates - Compare LastModified times
  4. Conditional Download - Download only if S3 version is newer

Common Errors​

Error: "NoSuchKey: The specified key does not exist"

  • Solution: Verify the object name is correct, including the full path with prefixes

Error: "NoSuchBucket: The specified bucket does not exist"

  • Solution: Verify the bucket name is correct and the bucket exists

Error: "Access Denied"

  • Solution: Ensure your credentials have the s3:GetObject permission

Error: "Invalid Client ID"

  • Solution: Verify the Client ID from the Connect node is being passed correctly

Performance Benefits​

  • Much faster than downloading the file (no data transfer)
  • Minimal bandwidth usage
  • No disk space required
  • Can query thousands of objects quickly
  • Useful for building file catalogs or indexes
  • Ideal for validation and verification workflows