helpers.rs

  1// Copyright (c) 2017 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
  2//
  3// This Source Code Form is subject to the terms of the Mozilla Public
  4// License, v. 2.0. If a copy of the MPL was not distributed with this
  5// file, You can obtain one at http://mozilla.org/MPL/2.0/.
  6
  7use crate::util::error::Error;
  8use jid::Jid;
  9use std::str::FromStr;
 10
 11/// Codec for plain text content.
 12pub struct PlainText;
 13
 14impl PlainText {
 15    pub fn decode(s: &str) -> Result<Option<String>, Error> {
 16        Ok(match s {
 17            "" => None,
 18            text => Some(text.to_owned()),
 19        })
 20    }
 21
 22    pub fn encode(string: &Option<String>) -> Option<String> {
 23        string.as_ref().map(ToOwned::to_owned)
 24    }
 25}
 26
 27/// Codec for trimmed plain text content.
 28pub struct TrimmedPlainText;
 29
 30impl TrimmedPlainText {
 31    pub fn decode(s: &str) -> Result<String, Error> {
 32        Ok(match s.trim() {
 33            "" => return Err(Error::ParseError("URI missing in uri.")),
 34            text => text.to_owned(),
 35        })
 36    }
 37
 38    pub fn encode(string: &str) -> Option<String> {
 39        Some(string.to_owned())
 40    }
 41}
 42
 43/// Codec wrapping base64 encode/decode.
 44pub struct Base64;
 45
 46impl Base64 {
 47    pub fn decode(s: &str) -> Result<Vec<u8>, Error> {
 48        Ok(base64::decode(s)?)
 49    }
 50
 51    pub fn encode(b: &[u8]) -> Option<String> {
 52        Some(base64::encode(b))
 53    }
 54}
 55
 56/// Codec wrapping base64 encode/decode, while ignoring whitespace characters.
 57pub struct WhitespaceAwareBase64;
 58
 59impl WhitespaceAwareBase64 {
 60    pub fn decode(s: &str) -> Result<Vec<u8>, Error> {
 61        let s: String = s.chars().filter(|ch| *ch != ' ' && *ch != '\n' && *ch != '\t').collect();
 62        Ok(base64::decode(&s)?)
 63    }
 64
 65    pub fn encode(b: &[u8]) -> Option<String> {
 66        Some(base64::encode(b))
 67    }
 68}
 69
 70/// Codec for colon-separated bytes of uppercase hexadecimal.
 71pub struct ColonSeparatedHex;
 72
 73impl ColonSeparatedHex {
 74    pub fn decode(s: &str) -> Result<Vec<u8>, Error> {
 75        let mut bytes = vec![];
 76        for i in 0..(1 + s.len()) / 3 {
 77            let byte = u8::from_str_radix(&s[3 * i..3 * i + 2], 16)?;
 78            if 3 * i + 2 < s.len() {
 79                assert_eq!(&s[3 * i + 2..3 * i + 3], ":");
 80            }
 81            bytes.push(byte);
 82        }
 83        Ok(bytes)
 84    }
 85
 86    pub fn encode(b: &[u8]) -> Option<String> {
 87        let mut bytes = vec![];
 88        for byte in b {
 89            bytes.push(format!("{:02X}", byte));
 90        }
 91        Some(bytes.join(":"))
 92    }
 93}
 94
 95/// Codec for a JID.
 96pub struct JidCodec;
 97
 98impl JidCodec {
 99    pub fn decode(s: &str) -> Result<Jid, Error> {
100        Ok(Jid::from_str(s)?)
101    }
102
103    pub fn encode(jid: &Jid) -> Option<String> {
104        Some(jid.to_string())
105    }
106}