On Sat, Jul 7, 2018 at 1:19 AM, David Demelier via Boost-users wrote:

I was blindly doing:

cout << foo[field::location];

If `foo` is an instance of http::basic_fields, then the expression above should not produce the CRLF sequence. It should output only the value of the Location field. On Sat, Jul 7, 2018 at 1:43 AM, Richard Hodges via Boost-users wrote:

Out of interest, why do these functions return a const string_view?

To prevent assignments such as: foo[field::location] = "localhost:8080/index.html"; The statement above has no effect, the `const` annotation prevents it from compiling.

On Fri, 2018-07-06 at 08:31 -0700, Vinnie Falco via Boost-users wrote:

...

It will be more convenient as you don't need to trim them when you want to capture the field value.

You shouldn't have to do any trimming. basic_fields member functions and iterator value_type which return field values do so using a string_view, whose length excludes the trailing CRLF and also any colon and space. Callers should not assume the string is null-terminated, and work with the interface provided by string_view.

Okay, maybe I'm stupid or I don't understand something. I've done a simple request to google.fr and the http::response[field::location] still has CRLF even with the following code using value_type's value() function: if (res_.result() == status::moved_permanently) { const auto it = res_.find(field::location); if (it != res_.end()) cout << "new location: [" << it->value << "]" << std::endl; } The res_ object is a http::responsehttp::string_body, And once printed to the console I have: new location: [http://www.google.fr/ ] May I miss something from your original answer? Regards, -- David

On Sat, 2018-07-07 at 08:20 -0700, Vinnie Falco via Boost-users wrote:

On Sat, Jul 7, 2018 at 8:11 AM, David Demelier via Boost-users wrote:

...

The res_ object is a http::responsehttp::string_body, And once printed to the console I have:

new location: [http://www.google.fr/ ]

Hmm...that's not what I'm seeing. I added this function to test/beast/http/fields.cpp:

void testValue() { request req; req.insert(field::location, "http://www.google.fr/"); auto it = req.find(field::location); if(it != req.end()) log << "[" << it->value() << "]"; }

The output is:

beast.http.fields [http://www.google.fr/]25.6s, 1 suite, 1 case, 334 tests total, 0 failures The program '[0x6BF4] tests-beast-http.exe' has exited with code 0 (0x0).

If the CRLF was being included in the value, then none of these tests would pass, as the equalities would evaluate to false:

My bad, I apologize I wrongly converted the boost::string_view to std::string using the .data() member function and I just realized it's not null terminated... That's why my string was filled with random characters. Sorry for the noise! I should search how people convert boost::string_view to std::string in a convenient manner instead ;) Regards, -- David

Le sam. 7 juil. 2018 à 11:34, David Demelier via Boost-users < boost-users@lists.boost.org> a écrit :

On Sat, 2018-07-07 at 08:20 -0700, Vinnie Falco via Boost-users wrote:

...

On Sat, Jul 7, 2018 at 8:11 AM, David Demelier via Boost-users wrote:

...

The res_ object is a http::responsehttp::string_body, And once printed to the console I have:

new location: [http://www.google.fr/ ]

Hmm...that's not what I'm seeing. I added this function to test/beast/http/fields.cpp:

void testValue() { request req; req.insert(field::location, "http://www.google.fr/"); auto it = req.find(field::location); if(it != req.end()) log << "[" << it->value() << "]"; }

The output is:

beast.http.fields [http://www.google.fr/]25.6s, 1 suite, 1 case, 334 tests total, 0 failures The program '[0x6BF4] tests-beast-http.exe' has exited with code 0 (0x0).

If the CRLF was being included in the value, then none of these tests would pass, as the equalities would evaluate to false:

My bad, I apologize I wrongly converted the boost::string_view to std::string using the .data() member function and I just realized it's not null terminated... That's why my string was filled with random characters.

Why do you use data() without using size()/length() ? with string_view this is a recipe for hard to find bugs. At my job I've seen same behavior, and I am trying to explain to people that data() in std::string & std::string_view is mostly for C interfaces.

Sorry for the noise!

I should search how people convert boost::string_view to std::string in a convenient manner instead ;)

Regards,

-- David _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org https://lists.boost.org/mailman/listinfo.cgi/boost-users

-- Daniel «Il faut imaginer Sisyphe heureux» Albert Camus

On Sun, Jul 8, 2018 at 12:47 AM, David Demelier via Boost-users wrote:

I need to make a copy of the Beast's result.

What if there was a way to "detach" the field/value element from the container so that it could outlive the message? Would that be sufficient to allow you to avoid making a copy? Thanks