azure-functions-codegen 0.4.0

use crate::util::{
    to_camel_case, AttributeArguments, MacroError, QuotableBorrowedStr, QuotableDirection,
    QuotableOption, TryFrom,
};
use azure_functions_shared::codegen;
use quote::{quote, ToTokens};
use std::borrow::Cow;
use syn::spanned::Spanned;
use syn::Lit;

pub struct Table<'a>(pub Cow<'a, codegen::bindings::Table>);

impl TryFrom<AttributeArguments> for Table<'_> {
    type Error = MacroError;

    fn try_from(args: AttributeArguments) -> Result<Self, Self::Error> {
        let mut name = None;
        let mut table_name = None;
        let mut partition_key = None;
        let mut row_key = None;
        let mut filter = None;
        let mut take = None;
        let mut connection = None;

        for (key, value) in args.list.iter() {
            let key_str = key.to_string();

            match key_str.as_str() {
                "name" => match value {
                    Lit::Str(s) => {
                        name = Some(Cow::Owned(to_camel_case(&s.value())));
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal string value for the 'name' argument",
                        )
                            .into());
                    }
                },
                "table_name" => match value {
                    Lit::Str(s) => {
                        table_name = Some(Cow::Owned(s.value()));
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal string value for the 'table_name' argument",
                        )
                            .into());
                    }
                },
                "partition_key" => match value {
                    Lit::Str(s) => {
                        partition_key = Some(Cow::Owned(s.value()));
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal string value for the 'partition_key' argument",
                        )
                            .into());
                    }
                },
                "row_key" => match value {
                    Lit::Str(s) => {
                        row_key = Some(Cow::Owned(s.value()));
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal string value for the 'row_key' argument",
                        )
                            .into());
                    }
                },
                "filter" => match value {
                    Lit::Str(s) => {
                        filter = Some(Cow::Owned(s.value()));
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal string value for the 'filter' argument",
                        )
                            .into());
                    }
                },
                "take" => match value {
                    Lit::Int(i) => {
                        take = Some(i.value());
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal integer value for the 'take' argument",
                        )
                            .into());
                    }
                },
                "connection" => match value {
                    Lit::Str(s) => {
                        connection = Some(Cow::Owned(s.value()));
                    }
                    _ => {
                        return Err((
                            value.span(),
                            "expected a literal string value for the 'connection' argument",
                        )
                            .into());
                    }
                },
                _ => {
                    return Err((
                        key.span(),
                        format!("unsupported binding attribute argument '{}'", key_str).as_ref(),
                    )
                        .into());
                }
            };
        }

        if table_name.is_none() {
            return Err((
                args.span,
                "the 'table_name' argument is required for table bindings.",
            )
                .into());
        }

        Ok(Table(Cow::Owned(codegen::bindings::Table {
            name: name.expect("expected a name for a table binding"),
            table_name: table_name.expect("expected a table name for a table binding"),
            partition_key,
            row_key,
            filter,
            take,
            connection,
            direction: codegen::Direction::In,
        })))
    }
}

impl ToTokens for Table<'_> {
    fn to_tokens(&self, tokens: &mut ::proc_macro2::TokenStream) {
        let name = QuotableBorrowedStr(&self.0.name);
        let table_name = QuotableBorrowedStr(&self.0.table_name);
        let partition_key = QuotableOption(
            self.0
                .partition_key
                .as_ref()
                .map(|x| QuotableBorrowedStr(x)),
        );
        let row_key = QuotableOption(self.0.row_key.as_ref().map(|x| QuotableBorrowedStr(x)));
        let filter = QuotableOption(self.0.filter.as_ref().map(|x| QuotableBorrowedStr(x)));
        let take = QuotableOption(self.0.take.as_ref());
        let connection = QuotableOption(self.0.connection.as_ref().map(|x| QuotableBorrowedStr(x)));
        let direction = QuotableDirection(self.0.direction.clone());

        quote!(::azure_functions::codegen::bindings::Table {
            name: #name,
            table_name: #table_name,
            partition_key: #partition_key,
            row_key: #row_key,
            filter: #filter,
            take: #take,
            connection: #connection,
            direction: #direction,
        })
        .to_tokens(tokens)
    }
}