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

// Copyright 2018-2022 Cargill Incorporated
// Copyright 2018 Bitwise IO, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Protobuf-encoded protocol structs.

use protobuf::Message;

#[derive(Debug)]
pub enum ProtoConversionError {
    DeserializationError(String),
    SerializationError(String),
    InvalidTypeError(String),
}

impl std::error::Error for ProtoConversionError {}

impl std::fmt::Display for ProtoConversionError {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        match *self {
            ProtoConversionError::DeserializationError(ref s) => {
                write!(f, "unable to deserialize during protobuf conversion: {}", s)
            }
            ProtoConversionError::SerializationError(ref s) => {
                write!(f, "unable to serialize during protobuf conversion: {}", s)
            }
            ProtoConversionError::InvalidTypeError(ref s) => write!(
                f,
                "invalid type encountered during protobuf conversion: {}",
                s
            ),
        }
    }
}

pub trait FromProto<P>: Sized {
    fn from_proto(other: P) -> Result<Self, ProtoConversionError>;
}

pub trait FromNative<N>: Sized {
    fn from_native(other: N) -> Result<Self, ProtoConversionError>;
}

/// Convert from bytes into a native struct, via the given protocol.
pub trait FromBytes<ViaProtocol>: Sized {
    fn from_bytes(bytes: &[u8]) -> Result<Self, ProtoConversionError>;
}

impl<P, N> FromBytes<P> for N
where
    P: protobuf::Message,
    N: FromProto<P>,
{
    fn from_bytes(bytes: &[u8]) -> Result<Self, ProtoConversionError> {
        let p: P = Message::parse_from_bytes(bytes)
            .map_err(|err| ProtoConversionError::DeserializationError(err.to_string()))?;
        N::from_proto(p)
    }
}

/// Convert to bytes from a native struct, via the given protocol.
pub trait IntoBytes<ViaProtocol>: Sized {
    fn into_bytes(self) -> Result<Vec<u8>, ProtoConversionError>;
}

impl<P, N> IntoBytes<P> for N
where
    P: protobuf::Message + FromNative<N>,
{
    fn into_bytes(self) -> Result<Vec<u8>, ProtoConversionError> {
        let p = P::from_native(self)?;
        p.write_to_bytes()
            .map_err(|err| ProtoConversionError::SerializationError(err.to_string()))
    }
}

pub trait IntoNative<T>: Sized {
    fn into_native(self) -> Result<T, ProtoConversionError>;
}

impl<N, P> IntoNative<N> for P
where
    N: FromProto<P>,
{
    fn into_native(self) -> Result<N, ProtoConversionError> {
        FromProto::from_proto(self)
    }
}

pub trait IntoProto<T>: Sized {
    fn into_proto(self) -> Result<T, ProtoConversionError>;
}

impl<N, P> IntoProto<P> for N
where
    P: FromNative<N>,
{
    fn into_proto(self) -> Result<P, ProtoConversionError> {
        FromNative::from_native(self)
    }
}

pub mod prelude {
    //! Allows for the convenient requirement of the proto conversion traits and errors.
    //!
    //! ```
    //! use splinter::protos::prelude::*;
    //! ```

    pub use super::FromBytes;
    pub use super::FromNative;
    pub use super::FromProto;
    pub use super::IntoBytes;
    pub use super::IntoNative;
    pub use super::IntoProto;
    pub use super::ProtoConversionError;
}

include!(concat!(env!("OUT_DIR"), "/protos/mod.rs"));