pancake_db_core/primitives/
strings.rs

1use pancake_db_idl::dml::field_value::Value;
2use pancake_db_idl::dtype::DataType;
3
4use crate::compression::Codec;
5use crate::compression::ZSTD;
6use crate::compression::zstd_codec::ZstdCodec;
7use crate::errors::{CoreError, CoreResult};
8use crate::primitives::Primitive;
9
10impl Primitive for String {
11  type A = u8;
12  const DTYPE: DataType = DataType::String;
13
14  const IS_ATOMIC: bool = false;
15
16  fn to_value(&self) -> Value {
17    Value::StringVal(self.clone())
18  }
19
20  fn try_from_value(v: &Value) -> CoreResult<String> {
21    match v {
22      Value::StringVal(res) => Ok(res.clone()),
23      _ => Err(CoreError::invalid("unable to extract string from value"))
24    }
25  }
26
27  fn to_atoms(&self) -> Vec<u8> {
28    self.as_bytes().to_vec()
29  }
30
31  fn try_from_atoms(atoms: &[u8]) -> CoreResult<Self> {
32    Ok(String::from_utf8(atoms.to_vec())?)
33  }
34
35  fn new_codec(codec: &str) -> Option<Box<dyn Codec<P=Self>>> {
36    if codec == ZSTD {
37      Some(Box::new(ZstdCodec::<String>::default()))
38    } else {
39      None
40    }
41  }
42}
43
44#[cfg(test)]
45mod tests {
46  use pancake_db_idl::dml::FieldValue;
47
48  use super::*;
49
50  #[test]
51  fn test_serde() -> CoreResult<()> {
52    let strs = vec!["orange", "banana", "grapefruit", "ÿ\\'\""];
53    let fvs = strs.iter()
54      .map(|s| FieldValue {
55        value: Some(Value::StringVal(s.to_string())),
56      })
57      .collect::<Vec<FieldValue>>();
58
59    let value_codec = String::new_value_codec(ZSTD).unwrap();
60
61    let bytes = value_codec.compress(&fvs, 0)?;
62    let recovered_values = value_codec.decompress(&bytes, 0)?;
63    assert_eq!(
64      fvs,
65      recovered_values,
66    );
67    Ok(())
68  }
69}
pancake_db_core/primitives/strings.rs

pancake_db_core/primitives/
strings.rs
