Add files via upload

src/main/java/stirling/software/SPDF/controller/FromPDFController.java

@@ -4,6 +4,10 @@ import java.io.IOException;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
@@ -23,10 +27,26 @@ public class FromPDFController {
 	}
 
 	@PostMapping("/convert-from-pdf")
-	public byte[] convertToImage(@RequestParam("fileInput") MultipartFile file,
+	public ResponseEntity<byte[]> convertToImage(@RequestParam("fileInput") MultipartFile file,
 			@RequestParam("imageFormat") String imageFormat) throws IOException {
 		byte[] pdfBytes = file.getBytes();
-		return PdfUtils.convertFromPdf(pdfBytes, imageFormat);
+		//returns bytes for image
+		byte[] result =  PdfUtils.convertFromPdf(pdfBytes, imageFormat.toLowerCase());
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(MediaType.parseMediaType(getMediaType(imageFormat)));
+		headers.setCacheControl("must-revalidate, post-check=0, pre-check=0");
+		ResponseEntity<byte[]> response = new ResponseEntity<>(result, headers, HttpStatus.OK);
+		return response;
 	}
 
+	private String getMediaType(String imageFormat) {
+	    if(imageFormat.equalsIgnoreCase("PNG"))
+	        return "image/png";
+	    else if(imageFormat.equalsIgnoreCase("JPEG"))
+	        return "image/jpeg";
+	    else if(imageFormat.equalsIgnoreCase("GIF"))
+	        return "image/gif";
+	    else
+	        return "application/octet-stream";
+	}
 }