iron_functions_derive/
lib.rs

1use proc_macro::TokenStream;
2use syn::{parse_macro_input, DeriveInput, Data, Error};
3
4/// `flink_input` indicates that a struct is used as an input for a Flink UDF.
5/// 
6/// This is a no-op macro that doesn't modify the annotated struct.
7///
8/// # Example
9///
10/// ```
11/// use iron_functions_sdk::*;
12///
13/// #[flink_input]
14/// struct MyInput {
15///     field1: String,
16///     field2: i32,
17/// }
18/// ```
19#[proc_macro_attribute]
20pub fn flink_input(_attr: TokenStream, item: TokenStream) -> TokenStream {
21    let item_clone = item.clone();
22    let input = parse_macro_input!(item_clone as DeriveInput);
23
24    // Check if the macro is applied to a struct
25    match input.data {
26        Data::Struct(_) => {
27            // If it's a struct, just return the original item
28            // This makes it a no-op macro
29            item
30        },
31        _ => {
32            Error::new_spanned(
33                proc_macro2::TokenStream::from(item),
34                "#[flink_input] can only be used on structs"
35            )
36            .to_compile_error()
37            .into()
38        }
39    }
40}
41
42/// `flink_output` indicates that a struct is used as an output for a Flink UDF.
43/// 
44/// This is a no-op macro that doesn't modify the annotated struct.
45///
46/// # Example
47///
48/// ```
49/// use iron_functions_sdk::*;
50///
51/// #[flink_output]
52/// struct MyOutput {
53///     field1: String,
54///     field2: i32,
55/// }
56/// ```
57#[proc_macro_attribute]
58pub fn flink_output(_attr: TokenStream, item: TokenStream) -> TokenStream {
59    let item_clone = item.clone();
60    let input = parse_macro_input!(item_clone as DeriveInput);
61
62    // Check if the macro is applied to a struct
63    match input.data {
64        Data::Struct(_) => {
65            // If it's a struct, just return the original item
66            // This makes it a no-op macro
67            item
68        },
69        _ => {
70            Error::new_spanned(
71                proc_macro2::TokenStream::from(item),
72                "#[flink_output] can only be used on structs"
73            )
74            .to_compile_error()
75            .into()
76        }
77    }
78}
79
80#[proc_macro_derive(FlinkTypes, attributes(flink_type))]
81pub fn flink_types_derive(input: TokenStream) -> TokenStream {
82    let _input = parse_macro_input!(input as DeriveInput);
83
84    TokenStream::new()
85}
iron_functions_derive/lib.rs

iron_functions_derive/
lib.rs
