Postgres: Unexpected PortalSuspended when binding domain type of composite type of domain type

[demurgos]

Hi!
I get the following error when running a request with composite types:

Protocol("execute: unexpected message: PortalSuspended")

I wrote a minimal reproduction: demurgos@78cb672

Here is the setup code:

CREATE DOMAIN month_id AS INT2 CHECK (1 <= value AND value <= 12);
CREATE TYPE year_month AS (year INT4, month month_id);
CREATE DOMAIN winter_year_month AS year_month CHECK ((value).month <= 3);
CREATE TABLE heating_bills (
  month winter_year_month NOT NULL PRIMARY KEY,
  cost INT4 NOT NULL
);

This is inspired from real use cases in my applications: a domain type (month_id) adds some constraints, it is then used in a composite type (year_month) which is itself behind a domain type (winter_year_month) to add more constraints.

I implemented the corresponding Rust types encode/decode impls manually:

View encode/decode

    #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
    struct MonthId(i16);

    impl sqlx::Type<Postgres> for MonthId {
        fn type_info() -> sqlx::postgres::PgTypeInfo {
            sqlx::postgres::PgTypeInfo::with_name("month_id")
        }

        fn compatible(ty: &sqlx::postgres::PgTypeInfo) -> bool {
            *ty == Self::type_info()
        }
    }

    impl<'r> sqlx::Decode<'r, Postgres> for MonthId {
        fn decode(value: sqlx::postgres::PgValueRef<'r>) -> Result<Self, Box<dyn std::error::Error + 'static + Send + Sync>> {
            Ok(Self(<i16 as sqlx::Decode<Postgres>>::decode(value)?))
        }
    }

    impl<'q> sqlx::Encode<'q, Postgres> for MonthId {
        fn encode_by_ref(&self, buf: &mut sqlx::postgres::PgArgumentBuffer) -> sqlx::encode::IsNull {
            self.0.encode(buf)
        }
    }

    #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
    struct WinterYearMonth {
        year: i32,
        month: MonthId
    }

    impl sqlx::Type<Postgres> for WinterYearMonth {
        fn type_info() -> sqlx::postgres::PgTypeInfo {
            sqlx::postgres::PgTypeInfo::with_name("winter_year_month")
        }

        fn compatible(ty: &sqlx::postgres::PgTypeInfo) -> bool {
            *ty == Self::type_info()
        }
    }

    impl<'r> sqlx::Decode<'r, Postgres> for WinterYearMonth {
        fn decode(value: sqlx::postgres::PgValueRef<'r>) -> Result<Self, Box<dyn std::error::Error + 'static + Send + Sync>> {
            let mut decoder = sqlx::postgres::types::PgRecordDecoder::new(value)?;

            let year = decoder.try_decode::<i32>()?;
            let month = decoder.try_decode::<MonthId>()?;

            Ok(Self { year, month })
        }
    }

    impl<'q> sqlx::Encode<'q, Postgres> for WinterYearMonth {
        fn encode_by_ref(&self, buf: &mut sqlx::postgres::PgArgumentBuffer) -> sqlx::encode::IsNull {
            let mut encoder = sqlx::postgres::types::PgRecordEncoder::new(buf);
            encoder.encode(self.year);
            encoder.encode(self.month);
            encoder.finish();
            sqlx::encode::IsNull::No
        }
    }

And then tried to use them:

    let result = sqlx::query("INSERT INTO heating_bills(month, cost) VALUES($1::winter_year_month, 200)")
        .bind(WinterYearMonth { year: 2021, month: MonthId(2) })
        .execute(&mut conn)
        .await;

    let result = result.unwrap();

    assert_eq!(result.rows_affected(), 1);

This fails at the .unwrap step with the error Protocol("execute: unexpected message: PortalSuspended")

I believe this error is somehow related to oid cache for user types. The query fails only the first time its used. If I run it again, it succeeds:

    // Warm-up the oid cache 
    sqlx::query("INSERT INTO heating_bills(month, cost) VALUES($1::winter_year_month, 100)")
        .bind(WinterYearMonth { year: 2021, month: MonthId(1) })
        .execute(&mut conn)
        .await;

    // Now it succeeds
    let result = sqlx::query("INSERT INTO heating_bills(month, cost) VALUES($1::winter_year_month, 200)")
        .bind(WinterYearMonth { year: 2021, month: MonthId(2) })
        .execute(&mut conn)
        .await;

    let result = result.unwrap();

    assert_eq!(result.rows_affected(), 1);

I intend to look further into the issue and eventually submit a PR. I triggered this error with some complex types, but I believe that this is a more general issue with the communication with the database.

[demurgos]

I added support for PortalSuspended in the executor, only to figure out that the issue was elsewhere: domain types were not supported by postgres::connection::describe. Adding support for domain types fixed my issue, but I still think that there is an issue with how the executor handles suspended portals.

[demurgos]

The immediate issue I had was fixed by #1112.

Proper support for PortalSuspended should be tracked in its own issue.