boltr 0.2.0

Pure-Rust Bolt v5.x wire protocol library
Documentation 
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

//! Error types for the Bolt protocol.

use std::collections::HashMap;

use crate::types::BoltValue;

/// Errors that can occur during Bolt protocol operations.
#[derive(Debug, thiserror::Error)]
pub enum BoltError {
    #[error("protocol error: {0}")]
    Protocol(String),

    #[error("authentication error: {0}")]
    Authentication(String),

    #[error("session error: {0}")]
    Session(String),

    #[error("transaction error: {0}")]
    Transaction(String),

    #[error("query error {code}: {message}")]
    Query { code: String, message: String },

    #[error("resource exhausted: {0}")]
    ResourceExhausted(String),

    #[error("I/O error: {0}")]
    Io(#[from] std::io::Error),

    /// Permission denied: authenticated but lacks required role/permission.
    #[error("forbidden: {0}")]
    Forbidden(String),

    #[error("backend error: {0}")]
    Backend(String),

    #[cfg(feature = "ws")]
    #[error("WebSocket error: {0}")]
    WebSocket(String),
}

impl BoltError {
    /// Wraps any displayable error as a backend error.
    ///
    /// ```
    /// use boltr::error::BoltError;
    ///
    /// let err = BoltError::backend("table not found");
    /// assert_eq!(err.to_string(), "backend error: table not found");
    /// ```
    pub fn backend(e: impl std::fmt::Display) -> Self {
        Self::Backend(e.to_string())
    }

    /// Converts this error into a Bolt FAILURE metadata dictionary.
    ///
    /// Returns a map with `"code"` and `"message"` keys matching the
    /// Neo4j status code format.
    ///
    /// ```
    /// use boltr::error::BoltError;
    /// use boltr::types::BoltValue;
    ///
    /// let err = BoltError::Authentication("bad password".to_string());
    /// let meta = err.to_failure_metadata();
    ///
    /// assert_eq!(
    ///     meta.get("code"),
    ///     Some(&BoltValue::String("Neo.ClientError.Security.Unauthorized".to_string()))
    /// );
    /// assert_eq!(
    ///     meta.get("message"),
    ///     Some(&BoltValue::String("bad password".to_string()))
    /// );
    /// ```
    pub fn to_failure_metadata(&self) -> HashMap<String, BoltValue> {
        let (code, message) = match self {
            Self::Protocol(m) => ("Neo.ClientError.Request.Invalid", m.clone()),
            Self::Authentication(m) => ("Neo.ClientError.Security.Unauthorized", m.clone()),
            Self::Session(m) => ("Neo.ClientError.Request.Invalid", m.clone()),
            Self::Transaction(m) => (
                "Neo.ClientError.Transaction.TransactionStartFailed",
                m.clone(),
            ),
            Self::Query { code, message } => (code.as_str(), message.clone()),
            Self::ResourceExhausted(m) => (
                "Neo.TransientError.General.MemoryPoolOutOfMemoryError",
                m.clone(),
            ),
            Self::Io(e) => (
                "Neo.TransientError.General.DatabaseUnavailable",
                e.to_string(),
            ),
            Self::Forbidden(m) => ("Neo.ClientError.Security.Forbidden", m.clone()),
            Self::Backend(m) => ("Neo.DatabaseError.General.UnknownError", m.clone()),
            #[cfg(feature = "ws")]
            Self::WebSocket(m) => ("Neo.TransientError.General.DatabaseUnavailable", m.clone()),
        };
        HashMap::from([
            ("code".to_string(), BoltValue::String(code.to_string())),
            ("message".to_string(), BoltValue::String(message)),
        ])
    }
}

#[cfg(feature = "ws")]
impl From<tokio_tungstenite::tungstenite::Error> for BoltError {
    fn from(e: tokio_tungstenite::tungstenite::Error) -> Self {
        Self::WebSocket(e.to_string())
    }
}