Macro operation

macro_rules! operation {
    (@builder
        $(#[$outer:meta])*
        // The name of the operation and any generic params along with their constraints
        $name:ident<$($generic:ident: $first_constraint:ident $(+ $constraint:ident)* ),* $(+ $lt:lifetime)?>,
        // The client
        client: $client:ty,
        // The required fields that will be used in the constructor
        @required
        $($required:ident: $rtype:ty,)*
        // The optional fields that will have generated setters
        @optional
        $($optional:ident: $otype:ty,)*
        // The optional fields which won't have generated setters
        @nosetter
        $($nosetter:ident: $nstype:ty),*
        ) => { ... };
    (#[stream] $(#[$outer:meta])* $name:ident,
        client: $client:ty,
        $($required:ident: $rtype:ty,)*
        $(?$optional:ident: $otype:ty),*) => { ... };
    (#[stream] $(#[$outer:meta])*
        $name:ident,
        client: $client:ty,
        $($required:ident: $rtype:ty,)*
        $(?$optional:ident: $otype:ty,)*
        $(#[skip]$nosetter:ident: $nstype:ty),*
    ) => { ... };
    ($(#[$outer:meta])* $name:ident<$($generic:ident: $first_constraint:ident $(+ $constraint:ident)* ),* $(+ $lt:lifetime)?>,
        client: $client:ty,
        @required
        $($required:ident: $rtype:ty,)*
        @optional
        $($optional:ident: $otype:ty,)*
        @nosetter
        $($nosetter:ident: $nstype:ty),*
        ) => { ... };
    ($(#[$outer:meta])* $name:ident,
        client: $client:ty,
        $($required:ident: $rtype:ty,)*
        $(?$optional:ident: $otype:ty),*) => { ... };
    ($(#[$outer:meta])* $name:ident<$($generic:ident: $first_constraint:ident $(+ $constraint:ident)*),* $(+ $lt:lifetime)?>,
        client: $client:ty,
        $($required:ident: $rtype:ty,)*
        $(?$optional:ident: $otype:ty,)*
        $(#[skip] $nosetter:ident: $nstype:ty),*) => { ... };
}

Helper for constructing operations

For the following code:

azure_core::operation! {
   CreateCollection,
   client: DatabaseClient,
   collection_name: String,
   ?consistency_level: u32
}

The following code will be generated

#[derive(Debug, Clone)]
pub struct CreateCollectionBuilder {
    client: DatabaseClient,
    collection_name: String,
    consistency_level: Option<u32>,
    context: Context,
}

impl CreateCollectionBuilder {
    pub(crate) fn new(
        client: DatabaseClient,
        collection_name: String,
    ) -> Self {
        Self {
            client,
            collection_name,
            consistency_level: None,
            context: Context::new(),
        }
    }

    setters! {
        consistency_level: u32 => Some(consistency_level),
        context: Context => context,
    }
}

impl std::future::IntoFuture for CreateCollectionBuilder {
    type IntoFuture = CreateCollection;
    type Output = <CreateCollection as std::future::Future>::Output;
    fn into_future(self) -> Self::IntoFuture {
        Self::into_future(self)
    }
}

/// The future returned by calling `into_future` on the builder.
pub type CreateCollection =
    futures::future::BoxFuture<'static, azure_core::Result<CreateCollectionResponse>>;

Additionally, #[stream] can be used before the operation name to generate code appropriate for list operations and #[skip] can be used at the end of the list of options for options where we should not generate a setter.