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| 1 | +//! Manual zerompk wire format for [`SqlExpr`]. |
| 2 | +//! |
| 3 | +//! Each variant encodes as an array `[tag_u8, field1, field2, ...]`. Tags |
| 4 | +//! are stable and MUST NOT be renumbered — they are on-wire values in |
| 5 | +//! physical-plan envelopes. `Value`, `BinaryOp`, and `CastType` implement |
| 6 | +//! zerompk natively so they nest transparently. |
| 7 | +//! |
| 8 | +//! Tags: Column=0, Literal=1, BinaryOp=2, Negate=3, Function=4, Cast=5, |
| 9 | +//! Case=6, Coalesce=7, NullIf=8, IsNull=9, OldColumn=10. |
| 10 | +
|
| 11 | +use nodedb_types::Value; |
| 12 | + |
| 13 | +use super::types::{BinaryOp, CastType, SqlExpr}; |
| 14 | + |
| 15 | +impl zerompk::ToMessagePack for SqlExpr { |
| 16 | + fn write<W: zerompk::Write>(&self, writer: &mut W) -> zerompk::Result<()> { |
| 17 | + match self { |
| 18 | + SqlExpr::Column(s) => { |
| 19 | + writer.write_array_len(2)?; |
| 20 | + writer.write_u8(0)?; |
| 21 | + writer.write_string(s) |
| 22 | + } |
| 23 | + SqlExpr::Literal(v) => { |
| 24 | + writer.write_array_len(2)?; |
| 25 | + writer.write_u8(1)?; |
| 26 | + v.write(writer) |
| 27 | + } |
| 28 | + SqlExpr::BinaryOp { left, op, right } => { |
| 29 | + writer.write_array_len(4)?; |
| 30 | + writer.write_u8(2)?; |
| 31 | + left.write(writer)?; |
| 32 | + op.write(writer)?; |
| 33 | + right.write(writer) |
| 34 | + } |
| 35 | + SqlExpr::Negate(inner) => { |
| 36 | + writer.write_array_len(2)?; |
| 37 | + writer.write_u8(3)?; |
| 38 | + inner.write(writer) |
| 39 | + } |
| 40 | + SqlExpr::Function { name, args } => { |
| 41 | + writer.write_array_len(3)?; |
| 42 | + writer.write_u8(4)?; |
| 43 | + writer.write_string(name)?; |
| 44 | + args.write(writer) |
| 45 | + } |
| 46 | + SqlExpr::Cast { expr, to_type } => { |
| 47 | + writer.write_array_len(3)?; |
| 48 | + writer.write_u8(5)?; |
| 49 | + expr.write(writer)?; |
| 50 | + to_type.write(writer) |
| 51 | + } |
| 52 | + SqlExpr::Case { |
| 53 | + operand, |
| 54 | + when_thens, |
| 55 | + else_expr, |
| 56 | + } => { |
| 57 | + writer.write_array_len(4)?; |
| 58 | + writer.write_u8(6)?; |
| 59 | + operand.write(writer)?; |
| 60 | + writer.write_array_len(when_thens.len())?; |
| 61 | + for (cond, val) in when_thens { |
| 62 | + writer.write_array_len(2)?; |
| 63 | + cond.write(writer)?; |
| 64 | + val.write(writer)?; |
| 65 | + } |
| 66 | + else_expr.write(writer) |
| 67 | + } |
| 68 | + SqlExpr::Coalesce(exprs) => { |
| 69 | + writer.write_array_len(2)?; |
| 70 | + writer.write_u8(7)?; |
| 71 | + exprs.write(writer) |
| 72 | + } |
| 73 | + SqlExpr::NullIf(e1, e2) => { |
| 74 | + writer.write_array_len(3)?; |
| 75 | + writer.write_u8(8)?; |
| 76 | + e1.write(writer)?; |
| 77 | + e2.write(writer) |
| 78 | + } |
| 79 | + SqlExpr::IsNull { expr, negated } => { |
| 80 | + writer.write_array_len(3)?; |
| 81 | + writer.write_u8(9)?; |
| 82 | + expr.write(writer)?; |
| 83 | + writer.write_boolean(*negated) |
| 84 | + } |
| 85 | + SqlExpr::OldColumn(s) => { |
| 86 | + writer.write_array_len(2)?; |
| 87 | + writer.write_u8(10)?; |
| 88 | + writer.write_string(s) |
| 89 | + } |
| 90 | + } |
| 91 | + } |
| 92 | +} |
| 93 | + |
| 94 | +impl<'a> zerompk::FromMessagePack<'a> for SqlExpr { |
| 95 | + fn read<R: zerompk::Read<'a>>(reader: &mut R) -> zerompk::Result<Self> { |
| 96 | + let len = reader.read_array_len()?; |
| 97 | + if len == 0 { |
| 98 | + return Err(zerompk::Error::ArrayLengthMismatch { |
| 99 | + expected: 1, |
| 100 | + actual: 0, |
| 101 | + }); |
| 102 | + } |
| 103 | + let tag = reader.read_u8()?; |
| 104 | + match tag { |
| 105 | + 0 => Ok(SqlExpr::Column(reader.read_string()?.into_owned())), |
| 106 | + 1 => { |
| 107 | + let v = Value::read(reader)?; |
| 108 | + Ok(SqlExpr::Literal(v)) |
| 109 | + } |
| 110 | + 2 => { |
| 111 | + let left = SqlExpr::read(reader)?; |
| 112 | + let op = BinaryOp::read(reader)?; |
| 113 | + let right = SqlExpr::read(reader)?; |
| 114 | + Ok(SqlExpr::BinaryOp { |
| 115 | + left: Box::new(left), |
| 116 | + op, |
| 117 | + right: Box::new(right), |
| 118 | + }) |
| 119 | + } |
| 120 | + 3 => { |
| 121 | + let inner = SqlExpr::read(reader)?; |
| 122 | + Ok(SqlExpr::Negate(Box::new(inner))) |
| 123 | + } |
| 124 | + 4 => { |
| 125 | + let name = reader.read_string()?.into_owned(); |
| 126 | + let args = Vec::<SqlExpr>::read(reader)?; |
| 127 | + Ok(SqlExpr::Function { name, args }) |
| 128 | + } |
| 129 | + 5 => { |
| 130 | + let expr = SqlExpr::read(reader)?; |
| 131 | + let to_type = CastType::read(reader)?; |
| 132 | + Ok(SqlExpr::Cast { |
| 133 | + expr: Box::new(expr), |
| 134 | + to_type, |
| 135 | + }) |
| 136 | + } |
| 137 | + 6 => { |
| 138 | + let operand = Option::<Box<SqlExpr>>::read(reader)?; |
| 139 | + let wt_len = reader.read_array_len()?; |
| 140 | + let mut when_thens = Vec::with_capacity(wt_len); |
| 141 | + for _ in 0..wt_len { |
| 142 | + let pair_len = reader.read_array_len()?; |
| 143 | + if pair_len != 2 { |
| 144 | + return Err(zerompk::Error::ArrayLengthMismatch { |
| 145 | + expected: 2, |
| 146 | + actual: pair_len, |
| 147 | + }); |
| 148 | + } |
| 149 | + let cond = SqlExpr::read(reader)?; |
| 150 | + let val = SqlExpr::read(reader)?; |
| 151 | + when_thens.push((cond, val)); |
| 152 | + } |
| 153 | + let else_expr = Option::<Box<SqlExpr>>::read(reader)?; |
| 154 | + Ok(SqlExpr::Case { |
| 155 | + operand, |
| 156 | + when_thens, |
| 157 | + else_expr, |
| 158 | + }) |
| 159 | + } |
| 160 | + 7 => { |
| 161 | + let exprs = Vec::<SqlExpr>::read(reader)?; |
| 162 | + Ok(SqlExpr::Coalesce(exprs)) |
| 163 | + } |
| 164 | + 8 => { |
| 165 | + let e1 = SqlExpr::read(reader)?; |
| 166 | + let e2 = SqlExpr::read(reader)?; |
| 167 | + Ok(SqlExpr::NullIf(Box::new(e1), Box::new(e2))) |
| 168 | + } |
| 169 | + 9 => { |
| 170 | + let expr = SqlExpr::read(reader)?; |
| 171 | + let negated = reader.read_boolean()?; |
| 172 | + Ok(SqlExpr::IsNull { |
| 173 | + expr: Box::new(expr), |
| 174 | + negated, |
| 175 | + }) |
| 176 | + } |
| 177 | + 10 => Ok(SqlExpr::OldColumn(reader.read_string()?.into_owned())), |
| 178 | + _ => Err(zerompk::Error::InvalidMarker(tag)), |
| 179 | + } |
| 180 | + } |
| 181 | +} |
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