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use quote::ToTokens;
use syn::{Attribute, Lit, Meta, NestedMeta, Result};
#[derive(Debug, Default)]
pub struct ContainerAttributes {
pub varint: bool,
pub default: bool,
/// Encodes a numeric enum by the value of its descriminant
///
/// # Example
///
/// ```rust
/// #[derive(fluvio_protocol::derive::Encoder)]
/// #[fluvio(encode_discriminant)]
/// enum ValueEnum {
/// One = 1, // Encodes discriminant "1"
/// Two = 2, // Encodes discriminant "2"
/// }
/// ```
pub encode_discriminant: bool,
pub api_min_version: u16,
pub api_max_version: Option<u16>,
pub api_key: Option<u8>,
pub response: Option<String>,
pub repr_type_name: Option<String>,
}
impl ContainerAttributes {
pub fn from_ast(attributes: &[Attribute]) -> Result<ContainerAttributes> {
let mut cont_attr = ContainerAttributes::default();
// Find all supported container level attributes in one go
for attribute in attributes {
if attribute.path.is_ident("varint") {
cont_attr.varint = true;
} else if attribute.path.is_ident("fluvio") {
if let Ok(Meta::List(list)) = attribute.parse_meta() {
for kf_attr in list.nested {
if let NestedMeta::Meta(Meta::NameValue(name_value)) = kf_attr {
if name_value.path.is_ident("api_min_version") {
if let Lit::Int(lit_int) = &name_value.lit {
cont_attr.api_min_version = lit_int.base10_parse::<u16>()?;
}
} else if name_value.path.is_ident("api_max_version") {
if let Lit::Int(lit_int) = &name_value.lit {
cont_attr.api_max_version =
Some(lit_int.base10_parse::<u16>()?);
}
} else if name_value.path.is_ident("api_key") {
if let Lit::Int(lit_int) = &name_value.lit {
cont_attr.api_key = Some(lit_int.base10_parse::<u8>()?);
}
} else if name_value.path.is_ident("response") {
if let Lit::Str(lit_str) = &name_value.lit {
cont_attr.response = Some(lit_str.value());
}
} else {
tracing::warn!(
"#[fluvio({})] does nothing on the container.",
name_value.to_token_stream().to_string()
)
}
} else if let NestedMeta::Meta(Meta::Path(path)) = kf_attr {
if path.is_ident("default") {
cont_attr.default = true;
} else if path.is_ident("encode_discriminant") {
cont_attr.encode_discriminant = true;
} else {
tracing::warn!(
"#[fluvio({})] does nothing on the container.",
path.to_token_stream().to_string()
)
}
}
}
}
} else if attribute.path.is_ident("repr") {
if let Ok(Meta::List(list)) = attribute.parse_meta() {
for repr_attr in list.nested {
if let NestedMeta::Meta(Meta::Path(path)) = repr_attr {
if let Some(int_type) = path.get_ident() {
cont_attr.repr_type_name = Some(int_type.to_string());
}
}
}
}
}
}
Ok(cont_attr)
}
}