getAmazonHeaders | S-Drive Documentation

Returns a set of signed HTTP headers you can use to make an authenticated request directly to the storage bucket (S3/GCS) for a given file — for example, to fetch the file's bytes yourself, or confirm it exists, without generating a signed download URL first.

This is an optional, supporting piece of the upload/download process — most integrations won't need it unless they're making their own direct HTTP calls to storage. See Uploading a file end-to-end for where this could fit in.

How to call this method

global static Map<String,String> getAmazonHeaders(String item)

global static Map<String,String> getAmazonHeaders(String item, String versionId)

Parameters

Parameter	Type	Required	Description
`item`	`String`	Yes	The storage key of the object — this is the file record's `Key__c` field value (e.g. `cg__Key__c`), the same value you'd see as `fileLocation` in an `UploadRequestInfo`.
`versionId`	`String`	No	A specific version's Id, if the file lives in a version-enabled bucket and you want headers for that version rather than the current one.

Return value

Returns a Map<String,String> of HTTP header names to values — a signed (Version 4) request — that you attach to your own HttpRequest when calling the storage endpoint directly.

Notes

This method figures out which bucket the file lives in by matching item against existing file records with that key. If more than one record shares the key (which happens mid-new-version-upload), it resolves to the bucket used for new-version uploads.
This doesn't make the HTTP request for you — you still build and send the HttpRequest yourself using these headers.

Example

String storageKey = '500XX000001abcAAA/069XX0000004Cx1AAE/invoice.pdf';
Map<String,String> headers = SDriveTools.getAmazonHeaders(storageKey);

HttpRequest req = new HttpRequest();
req.setEndpoint('callout:S3_Named_Credential/' + storageKey); // or your bucket's full URL
req.setMethod('GET');
for (String key : headers.keySet()) {
    req.setHeader(key, headers.get(key));
}

Http http = new Http();
HttpResponse res = http.send(req);
System.debug('Status: ' + res.getStatusCode());