Struct zenoh::Selector

pub struct Selector {
    pub path_expr: PathExpr,
    pub predicate: String,
    pub filter: Option<String>,
    pub properties: Properties,
    pub fragment: Option<String>,
}

A zenoh Selector is the conjunction of a path expression identifying a set of paths and some optional parts allowing to refine the set of paths and associated values.

Structure of a selector:

/s1/s2/.../sn?x>1&y<2&...&z=4(p1=v1;p2=v2;...;pn=vn)[a;b;x;y;...;z]
|           | |             | |                   |  |           |
|-- expr ---| |--- filter --| |---- properties ---|  |--fragment-|

where:

• expr: is a PathExpr.
• filter: a list of predicates separated by '&' allowing to perform filtering on the values associated with the matching keys. Each predicate has the form “field-operator-value” value where:
  • field is the name of a field in the value (is applicable and is existing. otherwise the predicate is false)
  • operator is one of a comparison operators: < , > , <= , >= , = , !=
  • value is the the value to compare the field’s value with
• fragment: a list of fields names allowing to return a sub-part of each value. This feature only applies to structured values using a “self-describing” encoding, such as JSON or XML. It allows to select only some fields within the structure. A new structure with only the selected fields will be used in place of the original value.

NOTE: the filters and fragments are not yet supported in current zenoh version.

Fields

path_expr: PathExpr

the path expression part of this Selector (before ? character).

predicate: String

the predicate part of this Selector, as used in zenoh-net. I.e. all characters starting from ?.

filter: Option<String>

the filter part of this Selector, if any (all characters after ? and before ( or [)

properties: Properties

the properties part of this Selector (all characters between ( ) and after ?)

fragment: Option<String>

the fragment part of this Selector, if any (all characters between [ ] and after ?)

Implementations

impl Selector

pub fn with_prefix(&self, prefix: &Path) -> Selector

Returns the concatenation of prefix with this Selector.

pub fn strip_prefix(&self, prefix: &Path) -> Option<Self>

If this Selector starts with prefix returns a copy of this Selector with the prefix removed.
Otherwise, returns None.

pub fn is_relative(&self) -> bool

Returns true is this Selector is relative (i.e. not starting with '/').

pub fn matches(&self, path: &Path) -> bool

Returns true if path matches this Selector’s path expression.

pub fn has_time_range(&self) -> bool

Returns true if the Selector specifies a time-range in its properties (i.e. using "starttime" or "stoptime")

Trait Implementations

impl Clone for Selector

fn clone(&self) -> Selector

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Selector

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Selector

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq<Selector> for Selector

fn eq(&self, other: &Selector) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Selector) -> bool

This method tests for !=.

impl StructuralPartialEq for Selector

impl TryFrom<&'_ Query> for Selector

type Error = ZError

The type returned in the event of a conversion error.

fn try_from(q: &Query) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<&'_ str> for Selector

type Error = ZError

The type returned in the event of a conversion error.

fn try_from(s: &str) -> ZResult<Selector>

Performs the conversion.

impl TryFrom<String> for Selector

type Error = ZError

The type returned in the event of a conversion error.

fn try_from(s: String) -> Result<Self, Self::Error>

Performs the conversion.