ApexでawsへファイルDelete
public Integer fileUpload(Attachment file){
String attachmentBodyEncoded = EncodingUtil.base64Encode(file.Body);
String formattedDateString = Datetime.now().formatGMT('EEE, dd MMM yyyy HH:mm:ss z');
String key = awsAccessKey;
String secret = awsSecretAccessKey;
String bucketname = awsBucket;
String host = awsService + '-' + awsReign + '.amazonaws.com';
String method = 'DELETE';
String fileNameEncoded = EncodingUtil.urlEncode(file.Name, 'UTF-8');
HttpRequest req = new HttpRequest();
req.setMethod(method);
req.setEndpoint('https://' + bucketname + '.' + host + '/' + bucketname + '/' + fileNameEncoded);
req.setHeader('Host', bucketname + '.' + host);
req.setHeader('Content-Length', String.valueOf(attachmentBodyEncoded.length()));
req.setHeader('Content-Encoding', 'UTF-8');
req.setHeader('Content-type', file.ContentType);
req.setHeader('Connection', 'keep-alive');
req.setHeader('Date', formattedDateString);
req.setHeader('ACL', 'public-read-write');
req.setBodyAsBlob(EncodingUtil.base64Decode(attachmentBodyEncoded));
String stringToSign = 'DELETE\n\n' +
file.ContentType + '\n' +
formattedDateString + '\n' +
'/' + bucketname + '/' + bucketname + '/' + fileNameEncoded;
Blob mac = Crypto.generateMac('HMACSHA1', blob.valueof(stringToSign),blob.valueof(secret));
String signed = EncodingUtil.base64Encode(mac);
String authHeader = 'AWS' + ' ' + key + ':' + signed;
req.setHeader('Authorization',authHeader);
Http http = new Http();
HTTPResponse res = http.send(req);
return res.getStatusCode();
}