Play Framework : Sending CSV file as an attachment

Question

How to send a CSV file as an attachment in Play framework? I looked into the Play documentation by I didn't find what I'm looking for. I know I can return an input stream like that : ok(java.io.InputStream content, int chunkSize) but how to create and send the content to the csv file?

Answer 1

Play makes it easy to manipulate a HTTPResponse. You can find in the manual, how to add headers, set cookies etc. in a response.
The implementation differs according to the use case:

• Some string source is converted to csv file while sending to the client.
• An existing csv file is sent to the client.

Sending string as CSV file in a HTTPResponse

Play 2.4

static private final String CSV_FILE_NAME = "demo.csv";
...
public Result string2CsvFile() {  
   String csvContent = "f1,f2,f3,f4";  
   response().setContentType("text/csv");  
   response().setHeader(CONTENT_DISPOSITION,   
       String.format("attachment; filename=\"%s\"", CSV_FILE_NAME));  
   return ok(new ByteArrayInputStream(csvContent.getBytes()));  
}  

Play 2.5

static private final String CSV_FILE_NAME = "demo.csv";
...
public Result string2CsvFile() {  
   String csvContent = "f1,f2,f3,f4";  
    response().setHeader(CONTENT_DISPOSITION, 
            String.format("attachment; filename=\"%s\"", CSV_FILE_NAME));
    return ok(new ByteArrayInputStream(csvContent.getBytes())).as("text/csv");
}  

Sending existing CSV file in a HTTPResponse

Play 2.4

static private final String CSV_FILE_NAME = "demo.csv";
...
public Result attachCsvFile() {  
    response().setContentType("text/csv");
    response().setHeader(CONTENT_DISPOSITION, 
            String.format("attachment; filename=\"%s\"", CSV_FILE_NAME));
    return ok(Play.application().getFile(CSV_FILE));
}  

Play 2.5

 static private final String CSV_FILE_NAME = "demo.csv";
 ...
 public Result attachCsvFile() {  
    response().setHeader(CONTENT_DISPOSITION, 
       String.format("attachment; filename=\"%s\"", CSV_FILE_NAME));
    return ok(Play.current().getFile(CSV_FILE)).as("text/csv");
}