API development - flatten different structs to pass as Query Parameters

1

I am developing an API (based on actix) and across all the routes there are several classes of query parameters that I want to allow for different routes. I am setting up structs for the parameters like:

// just a Test struct
#[derive(Debug, Deserialize, Serialize)]
pub struct Test {
    pub limit: Option<usize>,
    pub pt: Option<usize>,
}

// Struct for data subsetting
#[derive(Debug, Serialize, Deserialize)]
pub struct DataSubsetting {
    pub subset: String,
    pub datetime: String,
    pub properties: Vec<String>,
    pub exclude_properties: Vec<String>,
}

Now I want to use these structs in e.g. my /data route and therefore I "combine" my structs into a QueryParameter struct by flattening them with serde...

#[derive(Debug, Deserialize, Serialize)]
pub struct QueryParams {
    #[serde(flatten)]
    pub limitandtest: Option<Test>,
    #[serde(flatten)]
    pub data_subsetting: Option<DataSubsetting>,

... be able to pass it to my data_handler function like so.

pub async fn data_handler(query: web::Query<QueryParams>) -> impl Responder { 
    if let Some(subsetting) = &query.data_subsetting {
        println!("Subset: {:?}", subsetting);
        println!("Subset: {:?}", subsetting.subset);
    }
    if let Some(test) = &query.limitandtest {
        println!("limitandtest: {:?}", test);
    }
}

I followed this but was not able to get any values in the println! statements except the structure of the QueryParams variable with all values being None. However, if I just pass Test to the data_handler I get my desired output. What is wrong with the way I write my QueryParams struct?

I also saw this, but it does not seem to satisfy my requirements as the possible query parameters are static and will not change at all.

Any help is much appreciated!

2

Changing this

to this

// Struct for data subsetting
#[derive(Debug, Serialize, Deserialize)]
pub struct DataSubsetting {
    pub subset: Option<String>,
    pub datetime: Option<String>,
    pub properties: Option<Vec<String>>,
    pub exclude_properties: Option<Vec<String>>,
}

solved the issue.