Is this possible to write bytes to response?

[48cf]

All I saw is able to use with crow::response::write is a std::string. I would like to be able to write raw bytes to my response. Is this possible? If so, how am I able to do that?

[mrozigor]

Can't you just create string from bytes (with constructor)? If you want to send raw bytes, then you should probably use sockets directly.

[48cf]

I want to achieve the behavior of JavaScript's buffer objects.

On Tue, Jun 5, 2018 at 9:40 PM, Igor Mroz notifications@github.com wrote:

Can't you just create string from bytes (with constructor)? If you want to send raw bytes, then you should probably use sockets directly.

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[mrozigor]

Can you show example?

[48cf]

Uhh... The best thing I can do is log a Buffer object to console.

console.log(new Buffer("test")); results in: <Buffer 74 65 73 74>

I think Python's buffer = bytes() is a good representation too.

[mrozigor]

So you want to send bytes to socket. I think that you need raw socket to do this (https://www.geeksforgeeks.org/socket-programming-cc/). Or maybe send bytes as hex representation (https://stackoverflow.com/questions/10599068/how-do-i-print-bytes-as-hexadecimal) in HTTP response body and then reinterpret them on other side.

[48cf]

I can't use socket. I need to send response in that format to a HTTP server. Maybe i should just make a char buffer and "write bytes" to it? And In the end construct a string from it and send it back.

[mrozigor]

But HTTP protocol is a text protocol (as name states). If you need to send bytes to HTTP server then you can send theirs hex representation and then parse it back. Or send text representation of bytes (with std::string constructor).

[48cf]

Yeah, that's what I mean! Send their hexadecimal representation to the server! Is this possible with crow?

[mrozigor]

As I replied earlier - you have to convert bytes into hex string and then write it to response. I put link on how to perform this conversion in one of the earlier posts.

On 13 June 2018 14:28:50 CEST, czapek notifications@github.com wrote:

Yeah, that's what I mean! Send their hexadecimal representation to the server! Is this possible with crow?

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[pierobot]

Just use std::string. It can hold literally anything you want so long as you use it correctly.

If the other side of the connection expects raw data as the body of the response then it can be something as simple as

CROW_ROUTE(...)([...](...) -> crow::response
{
    char buffer[4] = { '\x76', '\x65', '\x73', '\x74'};
    auto response = crow::response(std::string(&buffer[0], sizeof(buffer)));
    // add whatever headers you need
    //response.set_header("Content-Type", "application/octet-stream");

    return response;
});

A somewhat more concrete example if you're trying to send a file

std::string const get_file_contents(...)
{
    std::string file_contents;
    file_contents.resize(file_size);

    // ... read to &file_contents[0]

    return file_contents;
}

CROW_ROUTE(...)([...](...) -> crow::response
{
    auto response = crow::response(get_file_contents(...));
    // add whatever headers you need
    //response.set_header("Content-Type", "application/octet-stream");

    return response;
});