diesel/mysql/types/
json.rs

1use crate::deserialize::{self, FromSql};
2use crate::mysql::{Mysql, MysqlValue};
3use crate::serialize::{self, IsNull, Output, ToSql};
4use crate::sql_types;
5
6#[cfg(all(feature = "mysql_backend", feature = "serde_json"))]
7impl FromSql<sql_types::Json, Mysql> for serde_json::Value {
8    fn from_sql(value: MysqlValue<'_>) -> deserialize::Result<Self> {
9        serde_json::from_slice(value.as_bytes()).map_err(|_| "Invalid Json".into())
10    }
11}
12
13#[cfg(all(feature = "mysql_backend", feature = "serde_json"))]
14impl ToSql<sql_types::Json, Mysql> for serde_json::Value {
15    fn to_sql<'b>(&'b self, out: &mut Output<'b, '_, Mysql>) -> serialize::Result {
16        serde_json::to_writer(out, self)
17            .map(|_| IsNull::No)
18            .map_err(Into::into)
19    }
20}
21
22#[cfg(test)]
23mod tests {
24    use super::*;
25    #[diesel_test_helper::test]
26    fn json_to_sql() {
27        use crate::query_builder::bind_collector::ByteWrapper;
28
29        let mut buffer = Vec::new();
30        let mut bytes = Output::test(ByteWrapper(&mut buffer));
31        let test_json = serde_json::Value::Bool(true);
32        ToSql::<sql_types::Json, Mysql>::to_sql(&test_json, &mut bytes).unwrap();
33        assert_eq!(buffer, b"true");
34    }
35
36    #[diesel_test_helper::test]
37    fn some_json_from_sql() {
38        use crate::mysql::MysqlType;
39        let input_json = b"true";
40        let output_json: serde_json::Value = FromSql::<sql_types::Json, Mysql>::from_sql(
41            MysqlValue::new_internal(input_json, MysqlType::String),
42        )
43        .unwrap();
44        assert_eq!(output_json, serde_json::Value::Bool(true));
45    }
46
47    #[diesel_test_helper::test]
48    fn bad_json_from_sql() {
49        use crate::mysql::MysqlType;
50        let uuid: Result<serde_json::Value, _> = FromSql::<sql_types::Json, Mysql>::from_sql(
51            MysqlValue::new_internal(b"boom", MysqlType::String),
52        );
53        assert_eq!(uuid.unwrap_err().to_string(), "Invalid Json");
54    }
55
56    #[diesel_test_helper::test]
57    fn no_json_from_sql() {
58        let uuid: Result<serde_json::Value, _> =
59            FromSql::<sql_types::Json, Mysql>::from_nullable_sql(None);
60        assert_eq!(
61            uuid.unwrap_err().to_string(),
62            "Unexpected null for non-null column"
63        );
64    }
65}