Junit HTTP request test with Apache SS Workbook? - spring

Question

My restful service accepts a file argument, the contents of which is an Apache SS (XSSF) Workbook. The method iterates through the cells of the Workbook and takes various actions, based on the values of the cells.
I've conceived a Junit test where I instantiate and populate an Apache SS Workbook, add it to a 'file'object and then pass the 'file' object to the method under test. The primary problem that I'm having is how to instantiate the 'file' object using the Workbook object.
Following is a sample of the method under test (omitting details unrelated to the Workbook), followed by a pseudo-code example of what I'm trying to do:
/* Method under test */
public Object workbookProcessing(HttpServletRequest request) {
List<Part> workbookParts = request.getParts().collect(Collectors.toList());
for (Part workbookPart : workbookParts) {
InputStream workbookContent = workbookPart.getInputStream();
Workbook workbook = WorkbookFactory.create(workbookContent);
// ...
}
/* Junit test pseudo-code */
public void testWorkbookProcessing() {
RestfulService rs = new RestfulService();
Workbook wb = WorkbookFactory.create(true) // Create XSSF workbook
CreationHelper createHelper = wb.getCreationHelper();
Sheet sheet = wb.createSheet("Sheet 1");
Row row = sheet.createRow(0);
row.createCell(0).setCellValue(createHelper.createRichTextString("Row 1 Cell 1"));
row.createCell(1).setCellValue(12345678);
// ...
HttpServletRequest request = new HttpServletRequest(); // Create HttpServletRequest
// Create InputStream, using above Workbook <- Help!
// Create Part object from InputStream <- Help!
request.addPart(inputStream); // Add Part object to request
ResponseEntity re = rs.workbookProcessing(request);
assertEquals(200, re.getStatusCodeValue());
}
Alternatively, if there is a way to Mock the workbook and it's cell values, I'm happy to do that as well.

Answer 1

After quite a bit of research, trial and error and combining techniques, here is how I was able to write a working Junit test to submit a multi-part HTTP request which contained an Apache SS workbook object.
// Working Junit test code:
#Test
public void testWorkbookProcessing() {
RestfulService rs = new RestfulService();
Workbook wb = WorkbookFactory.create(true) // Create XSSF workbook
CreationHelper createHelper = wb.getCreationHelper();
Sheet sheet = wb.createSheet("Sheet 1");
Row row = sheet.createRow(0); // First row of sheet
row.createCell(0).setCellValue(createHelper.createRichTextString("Row 1 Cell 1"));
row.createCell(1).setCellValue(12345678);
// ...
// This is the code to create the multi-part content
ByteArrayOutputStream baos = New ByteArrayOutputStream();
wb.write(baos); // Write workbook to output stream
byte[] bytes = baos.toByteArray(); // Convert output stream to byte array
MockPart part = new MockPart("file", "test_filename.xlsx", bytes); // Add byte array to mocked Part object
MockMultipartHttpServletRequest request = new MockMultipartHttpServletRequest();
request.setMethod(RequestMethod.POST.name());
request.addHeader("Content-Type", "multipart/form-data");
request.addParameter("id", "12345678"); // optional
request.addPart(part); // Add Part to request
ResponseEntity re = rs.workbookProcessing(request);
assertEquals(202, re.getStatusCodeValue());
}
Refinements/comments/suggestions appreciated.