1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144

use crate::{error::Error, helper, AvroValue, Map, Record};
use futures::TryStreamExt;
use serde::{
    de::DeserializeOwned,
    ser::{self, Serialize, SerializeMap, Serializer},
};
use sqlx::{database::HasValueRef, Column, ColumnIndex, Database, Decode, Row, TypeInfo, ValueRef};
use std::borrow::Cow;

/// A generic struct for the row.
pub(super) struct SerializeRow<R: Row>(pub(super) R);

impl<'r, R: Row> Serialize for &'r SerializeRow<R>
where
    usize: ColumnIndex<R>,
    Cow<'r, str>: Decode<'r, <R as Row>::Database>,
    f64: Decode<'r, <R as Row>::Database>,
    i64: Decode<'r, <R as Row>::Database>,
    bool: Decode<'r, <R as Row>::Database>,
{
    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
        let columns = self.0.columns();
        let mut map = serializer.serialize_map(Some(columns.len()))?;
        for col in columns {
            let key = col.name();
            match self.0.try_get_raw(col.ordinal()) {
                Ok(raw_value) if !raw_value.is_null() => match raw_value.type_info().name() {
                    "BOOL" | "BOOLEAN" => map_serialize::<_, _, bool>(&mut map, key, raw_value)?,
                    "DOUBLE" | "DOUBLE PRECISION" | "FLOAT" | "FLOAT4" | "FLOAT8" | "NUMERIC"
                    | "REAL" => map_serialize::<_, _, f64>(&mut map, key, raw_value)?,
                    "BIGINT" | "BIGINT UNSIGNED" | "BIGSERIAL" | "INT" | "INT2" | "INT4"
                    | "INT8" | "INTEGER" | "INT UNSIGNED" | "SERIAL" | "SMALLINT"
                    | "SMALLINT UNSIGNED" | "SMALLSERIAL" | "TINYINT" | "TINYINT UNSIGNED" => {
                        map_serialize::<_, _, i64>(&mut map, key, raw_value)?
                    }
                    // Deserialize as a string by default
                    _ => map_serialize::<_, _, Cow<'_, str>>(&mut map, key, raw_value)?,
                },
                _ => map.serialize_entry(key, &())?, // Serialize null
            }
        }
        map.end()
    }
}

fn map_serialize<'r, M: SerializeMap, DB: Database, T: Decode<'r, DB> + Serialize>(
    map: &mut M,
    key: &str,
    raw_value: <DB as HasValueRef<'r>>::ValueRef,
) -> Result<(), M::Error> {
    let value = T::decode(raw_value).map_err(ser::Error::custom)?;
    map.serialize_entry(key, &value)
}

pub(super) macro impl_sqlx_connector($pool:ty) {
    async fn execute(&self, query: &str, params: Option<&Map>) -> Result<Option<u64>, Error> {
        let (sql, values) = helper::prepare_sql_query(query, params, '?');
        let mut query = sqlx::query(&sql);
        for value in values {
            query = query.bind(value.to_string());
        }

        let query_result = query.execute(self).await?;
        Ok(Some(query_result.rows_affected()))
    }

    async fn query(&self, query: &str, params: Option<&Map>) -> Result<Vec<Record>, Error> {
        let (sql, values) = helper::prepare_sql_query(query, params, '?');
        let mut query = sqlx::query(&sql);
        for value in values {
            query = query.bind(value.to_string());
        }

        let mut rows = query.fetch(self);
        let mut records = Vec::new();
        while let Some(row) = rows.try_next().await? {
            let value = apache_avro::to_value(&SerializeRow(row))?;
            if let AvroValue::Record(record) = value {
                records.push(record);
            }
        }
        Ok(records)
    }

    async fn query_as<T: DeserializeOwned>(
        &self,
        query: &str,
        params: Option<&Map>,
    ) -> Result<Vec<T>, Error> {
        let (sql, values) = helper::prepare_sql_query(query, params, '?');
        let mut query = sqlx::query(&sql);
        for value in values {
            query = query.bind(value.to_string());
        }

        let mut rows = query.fetch(self);
        let mut data = Vec::new();
        while let Some(row) = rows.try_next().await? {
            let json_value = serde_json::to_value(&SerializeRow(row))?;
            let value = serde_json::from_value(json_value)?;
            data.push(value);
        }
        Ok(data)
    }

    async fn query_one(&self, query: &str, params: Option<&Map>) -> Result<Option<Record>, Error> {
        let (sql, values) = helper::prepare_sql_query(query, params, '?');
        let mut query = sqlx::query(&sql);
        for value in values {
            query = query.bind(value.to_string());
        }

        let data = if let Some(row) = query.fetch_optional(self).await? {
            let value = apache_avro::to_value(&SerializeRow(row))?;
            if let AvroValue::Record(record) = value {
                Some(record)
            } else {
                None
            }
        } else {
            None
        };
        Ok(data)
    }

    async fn query_one_as<T: DeserializeOwned>(
        &self,
        query: &str,
        params: Option<&Map>,
    ) -> Result<Option<T>, Error> {
        let (sql, values) = helper::prepare_sql_query(query, params, '?');
        let mut query = sqlx::query(&sql);
        for value in values {
            query = query.bind(value.to_string());
        }

        if let Some(row) = query.fetch_optional(self).await? {
            let json_value = serde_json::to_value(&SerializeRow(row))?;
            serde_json::from_value(json_value).map_err(Error::from)
        } else {
            Ok(None)
        }
    }
}