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
131
132
133
134
135
136
137
138

//
// Copyright (c) 2017, 2020 ADLINK Technology Inc.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License 2.0 which is available at
// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
//
// Contributors:
//   ADLINK zenoh team, <zenoh@adlink-labs.tech>
//
use crate::net::utils::resource_name;
use crate::net::ResKey;
use crate::Path;
use std::convert::{From, TryFrom};
use std::fmt;
use zenoh_util::core::{ZError, ZErrorKind, ZResult};
use zenoh_util::zerror;

/// A zenoh Path Expression used to express a selection of [`Path`]s.
///
/// Similarly to a [`Path`], a Path is a set of strings separated by '/' , as in a filesystem path.
/// But unlike a [`Path`] it can contain `'*'` characters:
///  - a single `'*'` character matches any set of characters in a path, except `'/'`.
///  - while `"**"` matches any set of characters in a path, including `'/'`.
///
/// A Path Expression can be absolute (i.e. starting with a `'/'`) or relative to a [`Workspace`](super::Workspace).
#[derive(Clone, Debug, PartialEq, Eq, Hash)]
pub struct PathExpr {
    pub(crate) p: String,
}

impl PathExpr {
    fn is_valid(path: &str) -> bool {
        !path.is_empty() && !path.contains(|c| c == '?' || c == '#' || c == '[' || c == ']')
    }

    /// Creates a new PathExpr from a String, checking its validity.  
    /// Returns `Err(`[`ZError`]`)` if not valid.
    pub fn new(p: String) -> ZResult<PathExpr> {
        if !Self::is_valid(&p) {
            zerror!(ZErrorKind::InvalidPathExpr { path: p })
        } else {
            Ok(PathExpr {
                p: Path::remove_useless_slashes(&p),
            })
        }
    }

    /// Returns the Path as a &str.
    pub fn as_str(&self) -> &str {
        self.p.as_str()
    }

    /// Returns true is this PathExpr is relative (i.e. not starting with `'/'`).
    pub fn is_relative(&self) -> bool {
        !self.p.starts_with('/')
    }

    /// Returns true is this PathExpr is a [`Path`] (i.e. not containing any `'*'`).
    pub fn is_a_path(&self) -> bool {
        !self.p.contains('*')
    }

    /// Returns the concatenation of `prefix` with this PathExpr.
    pub fn with_prefix(&self, prefix: &Path) -> Self {
        if self.is_relative() {
            Self {
                p: format!("{}/{}", prefix.p, self.p),
            }
        } else {
            Self {
                p: format!("{}{}", prefix.p, self.p),
            }
        }
    }

    /// If this PathExpr starts with `prefix` returns a copy of this PathExpr with the prefix removed.  
    /// Otherwise, returns `None`.
    pub fn strip_prefix(&self, prefix: &Path) -> Option<Self> {
        self.p
            .strip_prefix(&prefix.p)
            .map(|p| PathExpr { p: p.to_string() })
    }

    /// Returns true if `path` matches this PathExpr.
    pub fn matches(&self, path: &Path) -> bool {
        resource_name::intersect(&self.p, &path.p)
    }
}

impl fmt::Display for PathExpr {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}", self.p)
    }
}

impl TryFrom<String> for PathExpr {
    type Error = ZError;
    fn try_from(p: String) -> Result<Self, Self::Error> {
        PathExpr::new(p)
    }
}

impl TryFrom<&str> for PathExpr {
    type Error = ZError;
    fn try_from(p: &str) -> ZResult<PathExpr> {
        Self::try_from(p.to_string())
    }
}

impl From<&Path> for PathExpr {
    fn from(path: &Path) -> Self {
        // No need to check validity as PathExpr is valid
        PathExpr { p: path.p.clone() }
    }
}

impl From<Path> for PathExpr {
    fn from(path: Path) -> Self {
        // No need to check validity as PathExpr is valid
        PathExpr { p: path.p }
    }
}

impl From<PathExpr> for ResKey {
    fn from(path: PathExpr) -> Self {
        ResKey::from(path.p.as_str())
    }
}

impl From<&PathExpr> for ResKey {
    fn from(path: &PathExpr) -> Self {
        ResKey::from(path.p.as_str())
    }
}