get_method, get_uri on request::Builder

[kazuk]

I am writing Azure Storage REST Client and implementing Authorize with Shared Key. To create signatures, I need HTTP Method(VERB) , header values, and request URI on the current request. (See Blob, Queue, and File Services (Shared Key authorization))

I wish to add functions to request::Builder

• get_method
• get_uri
• get_headers

then I can implement sign_request as bellow

fn sign_request(&self, request_builder: Builder ) -> Builder {
    // build string_to_sign
    let string_to_sign =format!( "{}\n.....", request_builder.get_method(). ... );
    // compute signature 
    let signature = ....;
    // add Authorization header to Builder and return it.
    request_builder.header( AUTHORIZATION, "SharedKey {}:{}", self.account_name,signature )
}

Can you accept if I send changes?

Or is there any security reason that request::Builder shouldn't provide HTTP method etc?

[seanmonstar]

On one hand, it certainly seems reasonable to want to view what fields have already been set. On the other, I can't remember any other builder patterns where getters are included...

[kazuk]

https://en.wikipedia.org/wiki/Builder_pattern

C# builder having getter. because C# property MUST have getter.

C++,Java,etc builder not having getter.
But user can view current value from builder and update as bellow.

let temp_order = builder.build();
let tax = compute_tax( temp_order.item_lines() );
let taxed_order = builder.set_tax(tax).build();

in Rust, Builder consumed on first line build() and ends life. last line build() to make compilation error.

• from 'C# Builder' example, Builder have getter when language requirement or limitation hits situation.
• in Rust, Builder causes some of compilation errors, user do 'view current value'.

IMHO
'some of compilation errors' as 'language requirement or limitation hits situation' , and then Builder can have getter.

[carllerche]

I've wanted this every so often. I would be fine with having get_* functions.

[carllerche]

Though, if we are to bikeshed a bit, generally Rust doesn't have get_* prefix. We obviously can't have no prefix since that fn is used by the setter...

I'm leaning towards just adding get_ prefixes, but I'm open to other thoughts.

[kazuk]

Thank you ,
I send pull request #284,

generally Rust doesn't have get_* prefix. We obviously can't have no prefix since that fn is used by the setter...

Yes, and Yes,
get_ prefix for avoid the breaking changes.

[kazuk]

Merged! 🎉