redis_module/
error.rs

1use crate::RedisError;
2use std::error;
3use std::fmt;
4use std::fmt::Display;
5
6#[derive(Debug)]
7pub enum Error {
8    Generic(GenericError),
9    FromUtf8(std::string::FromUtf8Error),
10    ParseInt(std::num::ParseIntError),
11}
12
13impl Error {
14    #[must_use]
15    pub fn generic(message: &str) -> Self {
16        Self::Generic(GenericError::new(message))
17    }
18}
19
20impl From<RedisError> for Error {
21    fn from(err: RedisError) -> Self {
22        Self::generic(err.to_string().as_str())
23    }
24}
25
26impl From<std::string::FromUtf8Error> for Error {
27    fn from(err: std::string::FromUtf8Error) -> Self {
28        Self::FromUtf8(err)
29    }
30}
31
32impl From<std::num::ParseIntError> for Error {
33    fn from(err: std::num::ParseIntError) -> Self {
34        Self::ParseInt(err)
35    }
36}
37
38impl Display for Error {
39    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
40        match *self {
41            // Both underlying errors already impl `Display`, so we defer to
42            // their implementations.
43            Self::Generic(ref err) => write!(f, "{err}"),
44            Self::FromUtf8(ref err) => write!(f, "{err}"),
45            Self::ParseInt(ref err) => write!(f, "{err}"),
46        }
47    }
48}
49
50impl error::Error for Error {
51    fn cause(&self) -> Option<&dyn error::Error> {
52        match *self {
53            // N.B. Both of these implicitly cast `err` from their concrete
54            // types (either `&io::Error` or `&num::ParseIntError`)
55            // to a trait object `&Error`. This works because both error types
56            // implement `Error`.
57            Self::Generic(ref err) => Some(err),
58            Self::FromUtf8(ref err) => Some(err),
59            Self::ParseInt(ref err) => Some(err),
60        }
61    }
62}
63
64#[derive(Debug)]
65pub struct GenericError {
66    message: String,
67}
68
69impl GenericError {
70    #[must_use]
71    pub fn new(message: &str) -> Self {
72        Self {
73            message: String::from(message),
74        }
75    }
76}
77
78impl Display for GenericError {
79    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
80        write!(f, "Store error: {}", self.message)
81    }
82}
83
84impl error::Error for GenericError {
85    fn description(&self) -> &str {
86        self.message.as_str()
87    }
88
89    fn cause(&self) -> Option<&dyn error::Error> {
90        None
91    }
92}
redis_module/error.rs

redis_module/
error.rs
