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// Copyright 2019 Google LLC // // 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 // // https://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. // //! Mechanisms and constants for encoding and decoding [IETF-RFC6690 CoAP link-formats]. //! //! [IETF-RFC6690 CoAP link-formats]: https://tools.ietf.org/html/rfc6690 use super::*; use crate::uri::AnyUriRef; use std::borrow::Cow; use std::fmt::{Display, Write}; use std::iter::FusedIterator; /// Relation Type. /// /// From [IETF-RFC8288], [Section 3.3]: /// /// > The relation type of a link conveyed in the Link header field is /// > conveyed in the "rel" parameter's value. The rel parameter MUST be /// > present but MUST NOT appear more than once in a given link-value; /// > occurrences after the first MUST be ignored by parsers. /// > /// > The rel parameter can, however, contain multiple link relation types. /// > When this occurs, it establishes multiple links that share the same /// > context, target, and target attributes. /// > /// > The ABNF for the rel parameter values is: /// > /// > ```abnf /// > relation-type *( 1*SP relation-type ) /// > ``` /// > /// > where: /// > /// > ```abnf /// > relation-type = reg-rel-type / ext-rel-type /// > reg-rel-type = LOALPHA *( LOALPHA / DIGIT / "." / "-" ) /// > ext-rel-type = URI ; Section 3 of [RFC3986] /// > ``` /// > /// > Note that extension relation types are REQUIRED to be absolute URIs /// > in Link header fields and MUST be quoted when they contain characters /// > not allowed in tokens, such as a semicolon (";") or comma (",") (as /// > these characters are used as delimiters in the header field itself). /// /// Optional in [IETF-RFC6690] link format resources. /// /// [IETF-RFC8288]: https://tools.ietf.org/html/rfc8288 /// [Section 3.3]: https://tools.ietf.org/html/rfc8288#section-3.3 /// [IETF-RFC6690]: https://tools.ietf.org/html/rfc6690 pub const LINK_ATTR_REL: &'static str = "rel"; /// Anchor attribute. /// /// Provides an override of the document context URI when parsing relative URIs /// in the links. The value itself may be a relative URI, which is evaluated against the document /// context URI. /// /// * <a href="https://tools.ietf.org/html/rfc8288#section-3.2">RFC8288, Section 3.2</a> pub const LINK_ATTR_ANCHOR: &'static str = "anchor"; /// A hint indicating what the language of the result of dereferencing the link should be. /// /// * <a href="https://tools.ietf.org/html/rfc8288#section-3.4.1">RFC8288, Section 3.4.1</a> pub const LINK_ATTR_HREFLANG: &'static str = "hreflang"; /// Media Attribute. Used to indicate intended destination medium or media for style information. /// /// * <a href="https://tools.ietf.org/html/rfc8288#section-3.4.1">RFC8288, Section 3.4.1</a> pub const LINK_ATTR_MEDIA: &'static str = "media"; /// Human-readable label describing the resource. /// /// * <a href="https://tools.ietf.org/html/rfc8288#section-3.4.1">RFC8288, Section 3.4.1</a> pub const LINK_ATTR_TITLE: &'static str = "title"; /// Human-readable label describing the resource, along with language information. /// /// Is is typically formatted as `"utf-8'<LANG_CODE&>'<TITLE_TEXT>"`. For example: /// /// * `"utf-8'en'£ rates"`</code> /// /// Note that since <a href="https://tools.ietf.org/html/rfc6690">RFC6690</a> requires the link /// format serialization to always be in UTF-8 format, the value of this attribute MUST ALWAYS /// start with either the string <code>utf-8</code> or <code>UTF-8</code> and MUST NOT be /// percent-encoded. /// /// * <a href="https://tools.ietf.org/html/rfc8288#section-3.4.1">RFC8288, Section 3.4.1</a> /// * <a href="https://tools.ietf.org/html/rfc8187">RFC8187</a> pub const LINK_ATTR_TITLE_STAR: &'static str = "title*"; /// MIME content type attribute. /// /// This attribute should be avoided in favor of [`LINK_ATTR_CONTENT_FORMAT`]. /// /// * <a href="https://tools.ietf.org/html/rfc8288#section-3.4.1">RFC8288, Section 3.4.1</a> #[doc(hidden)] pub const LINK_ATTR_TYPE: &'static str = "type"; /// Resource Type Attribute. /// /// The Resource Type `rt` attribute is an opaque string used to assign /// an application-specific semantic type to a resource. One can think of this as a noun /// describing the resource. /// /// * <a href="https://tools.ietf.org/html/rfc6690#section-3.1">RFC6690, Section 3.1</a> pub const LINK_ATTR_RESOURCE_TYPE: &'static str = "rt"; /// Interface Description Attribute. /// /// The Interface Description `if` attribute is an opaque string /// used to provide a name or URI indicating a specific interface definition used to interact /// with the target resource. One can think of this as describing verbs usable on a resource. /// /// * <a href="https://tools.ietf.org/html/rfc6690#section-3.2">RFC6690, Section 3.2</a> /// pub const LINK_ATTR_INTERFACE_DESCRIPTION: &'static str = "if"; /// The estimated maximum size of the fetched resource. /// /// The maximum size estimate attribute `sz` /// gives an indication of the maximum size of the resource representation returned by performing /// a GET on the target URI. For links to CoAP resources, this attribute is not expected to be /// included for small resources that can comfortably be carried in a single Maximum Transmission /// Unit (MTU) but SHOULD be included for resources larger than that. The maximum size estimate /// attribute MUST NOT appear more than once in a link. /// /// * <a href="https://tools.ietf.org/html/rfc6690#section-3.3">RFC6690, Section 3.3</a> pub const LINK_ATTR_MAXIMUM_SIZE_ESTIMATE: &'static str = "sz"; /// The value of this resource expressed as a human-readable string. Must be less than 63 bytes. pub const LINK_ATTR_VALUE: &'static str = "v"; /// Content-Format Code(s). /// /// Space-separated list of content type integers appropriate for being /// specified in an Accept option. /// /// * <a href="https://tools.ietf.org/html/rfc7252#section-7.2.1">RFC7252, Section 7.2.1</a> pub const LINK_ATTR_CONTENT_FORMAT: &'static str = "ct"; /// Identifies this resource as observable if present. /// /// * <a href="https://tools.ietf.org/html/rfc7641#section-6">RFC7641, Section 6</a> pub const LINK_ATTR_OBSERVABLE: &'static str = "obs"; /// Name of the endpoint, max 63 bytes. /// /// * <a href="https://goo.gl/6e2s7C#section-5.3">draft-ietf-core-resource-directory-14</a> pub const LINK_ATTR_ENDPOINT_NAME: &'static str = "ep"; /// Lifetime of the registration in seconds. Valid values are between 60-4294967295, inclusive. /// /// * <a href="https://goo.gl/6e2s7C#section-5.3">draft-ietf-core-resource-directory-14</a> pub const LINK_ATTR_REGISTRATION_LIFETIME: &'static str = "lt"; /// Sector to which this endpoint belongs. Must be less than 63 bytes. /// /// * <a href="https://goo.gl/6e2s7C#section-5.3">draft-ietf-core-resource-directory-14</a> pub const LINK_ATTR_SECTOR: &'static str = "d"; /// The scheme, address and point and path at which this server is available. /// /// MUST be a valid URI. /// /// * <a href="https://goo.gl/6e2s7C#section-5.3">draft-ietf-core-resource-directory-14</a> pub const LINK_ATTR_REGISTRATION_BASE_URI: &'static str = "base"; /// Name of a group in this RD. Must be less than 63 bytes. /// /// * <a href="https://goo.gl/6e2s7C#section-6.1">draft-ietf-core-resource-directory-14</a> pub const LINK_ATTR_GROUP_NAME: &'static str = "gp"; /// Semantic name of the endpoint. Must be less than 63 bytes. /// /// * <a href="https://goo.gl/6e2s7C#section-10.3.1">draft-ietf-core-resource-directory-14</a> pub const LINK_ATTR_ENDPOINT_TYPE: &'static str = "et"; /// Error type for parsing a link format. #[derive(Copy, Clone, Debug, Eq, PartialEq)] pub enum ErrorLinkFormat { /// An error was encountered while parsing the link format. ParseError, } impl From<ErrorLinkFormat> for crate::Error { fn from(_: ErrorLinkFormat) -> Self { Error::ParseFailure } } const QUOTE_ESCAPE_CHAR: char = '\\'; const ATTR_SEPARATOR_CHAR: char = ';'; const LINK_SEPARATOR_CHAR: char = ','; /// Parsing iterator which parses a string formatted as an [IETF-RFC6690 CoAP link-format]. /// /// As successful parsing is performed, this iterator emits a tuple inside of a `Result::Ok`. /// The tuple contains a string slice for the link and a [`LinkAttributeParser`] to provide /// access to the link attributes for that link. /// /// Parsing errors are emitted as a `Result::Err` and are of the error type [`ErrorLinkFormat`]. /// /// [IETF-RFC6690 CoAP link-format]: https://tools.ietf.org/html/rfc6690 #[derive(Copy, Clone, Debug, Eq, PartialEq)] pub struct LinkFormatParser<'a> { pub(super) inner: &'a str, } impl<'a> LinkFormatParser<'a> { /// Creates a new instance of `LinkFormatParser` for the given string slice. pub fn new(inner: &'a str) -> LinkFormatParser<'a> { LinkFormatParser { inner } } } impl<'a> Iterator for LinkFormatParser<'a> { /// (uri-ref, link-attribute-iterator) type Item = Result<(&'a str, LinkAttributeParser<'a>), ErrorLinkFormat>; #[inline] fn next(&mut self) -> Option<Self::Item> { if self.inner.is_empty() { return None; } let mut iter = self.inner.chars(); // Proceed through whitespace until we get a '<'. loop { match iter.next() { Some(c) if c.is_ascii_whitespace() => continue, Some('<') => break, Some(_) => { self.inner = ""; return Some(Err(ErrorLinkFormat::ParseError)); } None => { self.inner = ""; return None; } } } let link_ref = iter.as_str(); // Proceed through characters until we get a '>'. while let Some(c) = iter.next() { if c == '>' { break; } } let link_len = iter.as_str().as_ptr() as usize - link_ref.as_ptr() as usize; let link_ref = (&link_ref[..link_len]).trim_end_matches('>'); let mut attr_keys = iter.as_str(); // Skip to the end of the attributes. We leave the // actual attribute parsing to `LinkAttributeParser`. loop { match iter.next() { Some(LINK_SEPARATOR_CHAR) | None => { break; } Some(c) if c == '"' => { // Handle quotes. loop { match iter.next() { Some('"') | None => break, Some(QUOTE_ESCAPE_CHAR) => { // Slashes always escape the next character, // since we are scanning and not parsing we // just skip it. iter.next(); } _ => (), } } } _ => (), } } let attr_len = iter.as_str().as_ptr() as usize - attr_keys.as_ptr() as usize; attr_keys = (&attr_keys[..attr_len]).trim_end_matches(LINK_SEPARATOR_CHAR); self.inner = iter.as_str(); return Some(Ok(( link_ref, LinkAttributeParser { inner: attr_keys.trim_matches(ATTR_SEPARATOR_CHAR), }, ))); } } /// Parsing iterator which parses link attributes for [IETF-RFC6690 CoAP link-format] processing. /// /// This iterator is emitted by [`LinkFormatParser`] while parsing a CoAP link-format. It emits /// a tuple for each attribute, with the first item being a string slice for the attribute key /// and the second item being an [`Unquote`] iterator for obtaining the value. A `String` or /// `Cow<str>` version of the value can be easily obtained by calling `to_string()` or `to_cow()` /// on the [`Unquote`] instance. /// /// This iterator is permissive and makes a best-effort to parse the link attributes and does not /// emit errors while parsing. /// /// [IETF-RFC6690 CoAP link-format]: https://tools.ietf.org/html/rfc6690 #[derive(Copy, Clone, Debug, Eq, PartialEq)] pub struct LinkAttributeParser<'a> { pub(super) inner: &'a str, } impl<'a> Iterator for LinkAttributeParser<'a> { /// (key_ref: &str, value-ref: Unquote) type Item = (&'a str, Unquote<'a>); #[inline] fn next(&mut self) -> Option<Self::Item> { if self.inner.is_empty() { return None; } let mut iter = self.inner.chars(); // Skip to the end of the attribute. loop { match iter.next() { Some(ATTR_SEPARATOR_CHAR) | None => { break; } Some(c) if c == '"' => { // Handle quotes. loop { match iter.next() { Some('"') | None => { break; } Some(QUOTE_ESCAPE_CHAR) => { iter.next(); } _ => (), } } } _ => (), } } let attr_len = iter.as_str().as_ptr() as usize - self.inner.as_ptr() as usize; let attr_str = &self.inner[..attr_len]; self.inner = iter.as_str(); let attr_str = attr_str.trim_end_matches(ATTR_SEPARATOR_CHAR); let (key, value) = if let Some(i) = attr_str.find('=') { let (key, value) = attr_str.split_at(i); (key, &value[1..]) } else { (attr_str, "") }; return Some((key.trim(), Unquote::new(value.trim()))); } } /// Character iterator which decodes a [IETF-RFC2616] [`quoted-string`]. /// Used by [`LinkAttributeParser`]. /// /// From [IETF-RFC2616] Section 2.2: /// /// > A string of text is parsed as a single word if it is quoted using /// > double-quote marks. /// > /// > ```abnf /// > quoted-string = ( <"> *(qdtext | quoted-pair ) <"> ) /// > qdtext = <any TEXT except <">> /// > ``` /// > /// > The backslash character ('\\') MAY be used as a single-character /// > quoting mechanism only within quoted-string and comment constructs. /// > /// > ```abnf /// > quoted-pair = "\" CHAR /// > ``` /// /// [IETF-RFC2616]: https://tools.ietf.org/html/rfc2616 /// [`quoted-string`]: https://tools.ietf.org/html/rfc2616#section-2.2 #[derive(Clone, Debug)] pub struct Unquote<'a> { inner: std::str::Chars<'a>, state: UnquoteState, } #[derive(Copy, Clone, Debug, Eq, PartialEq)] enum UnquoteState { NotStarted, NotQuoted, Quoted, } impl<'a> Eq for Unquote<'a> {} impl<'a> PartialEq for Unquote<'a> { fn eq(&self, other: &Self) -> bool { let self_s = self.inner.as_str(); let other_s = other.inner.as_str(); self.state == other.state && self_s.as_ptr() == other_s.as_ptr() && self_s.len() == other_s.len() } } impl<'a> From<Unquote<'a>> for Cow<'a, str> { fn from(iter: Unquote<'a>) -> Self { iter.to_cow() } } impl<'a> FusedIterator for Unquote<'a> {} impl<'a> Display for Unquote<'a> { fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result { self.clone().try_for_each(|c| f.write_char(c)) } } impl<'a> Unquote<'a> { /// Creates a new instance of the `Unquote` iterator from `quoted_str`. pub fn new(quoted_str: &'a str) -> Unquote<'a> { Unquote { inner: quoted_str.chars(), state: UnquoteState::NotStarted, } } /// Converts a fresh, unused instance of `Unquote` into the underlying raw string slice. /// /// Calling this method will panic if `next()` has been called. pub fn into_raw_str(self) -> &'a str { assert_eq!(self.state, UnquoteState::NotStarted); self.inner.as_str() } /// Returns the unquoted version of this string as a copy-on-write string. pub fn to_cow(&self) -> Cow<'a, str> { let str_ref = self.inner.as_str(); if self.is_quoted() { if str_ref.find('\\').is_some() { Cow::from(self.to_string()) } else { // String is quoted but has no escapes. Cow::from(&str_ref[1..str_ref.len() - 1]) } } else { Cow::from(str_ref) } } /// Returns true if the underlying string is quoted, false otherwise. pub fn is_quoted(&self) -> bool { match self.state { UnquoteState::NotStarted => self.inner.as_str().starts_with('"'), UnquoteState::NotQuoted => false, UnquoteState::Quoted => true, } } } impl<'a> Iterator for Unquote<'a> { type Item = char; #[inline] fn next(&mut self) -> Option<Self::Item> { loop { return match self.state { UnquoteState::NotStarted => match self.inner.next() { Some('"') => { self.state = UnquoteState::Quoted; // Go back to the start of the loop so we can hit // our "UnquoteState::Quoted" section below. continue; } c => { self.state = UnquoteState::NotQuoted; c } }, UnquoteState::NotQuoted => self.inner.next(), UnquoteState::Quoted => match self.inner.next() { Some('"') => { // We are finished. // Make ourselves empty so we can call ourselves "Fused" self.inner = "".chars(); None } Some(QUOTE_ESCAPE_CHAR) => self.inner.next(), c => c, }, }; } } } /// Helper for writing [IETF-RFC6690 CoAP link-formats] to anything implementing /// [`core::fmt::Write`]. /// /// ## Example /// /// ``` /// use async_coap::prelude::*; /// use async_coap::LinkFormatWrite; /// use async_coap::LINK_ATTR_INTERFACE_DESCRIPTION; /// /// // String implements core::fmt::Write /// let mut buffer = String::new(); /// /// let mut write = LinkFormatWrite::new(&mut buffer); /// /// write.link(uri_ref!("/sensor/light")) /// .attr_quoted(LINK_ATTR_INTERFACE_DESCRIPTION,"sensor") /// .finish() /// .expect("Error writing link"); /// /// assert_eq!(&buffer, r#"</sensor/light>;if="sensor""#); /// ``` /// /// [IETF-RFC6690 CoAP link-formats]: https://tools.ietf.org/html/rfc6690 #[derive(Debug)] pub struct LinkFormatWrite<'a, T: ?Sized> { write: &'a mut T, is_first: bool, add_newlines: bool, error: Option<core::fmt::Error>, } impl<'a, T: Write + ?Sized> LinkFormatWrite<'a, T> { /// Creates a new instance of `LinkFormatWriter` for a given instance that implements /// [`core::fmt::Write`]. pub fn new(write: &'a mut T) -> LinkFormatWrite<'a, T> { LinkFormatWrite { write, is_first: true, add_newlines: false, error: None, } } /// Sets whether newlines should be added or not between links, possibly improving /// human readability an the expense of a few extra bytes. pub fn set_add_newlines(&mut self, add_newlines: bool) { self.add_newlines = add_newlines; } /// Adds a link to the link format and returns [`LinkAttributeWrite`]. /// /// The returned [`LinkAttributeWrite`] instance can then be used to associate /// attributes to the link. pub fn link<'b, U: AnyUriRef + ?Sized>( &'b mut self, link: &U, ) -> LinkAttributeWrite<'a, 'b, T> { if self.is_first { self.is_first = false; } else if self.error.is_none() { self.error = self.write.write_char(LINK_SEPARATOR_CHAR).err(); if self.add_newlines { self.error = self.write.write_str("\n\r").err(); } } if self.error.is_none() { self.error = self.write.write_char('<').err(); } if self.error.is_none() { self.error = write!(self.write, "{}", link.display()).err(); } if self.error.is_none() { self.error = self.write.write_char('>').err(); } LinkAttributeWrite(self) } /// Consumes this [`LinkFormatWrite`] instance, returning any error that /// might have occurred during writing. pub fn finish(self) -> Result<(), core::fmt::Error> { if let Some(e) = self.error { Err(e) } else { Ok(()) } } } /// Helper for writing link format attributes; created by calling [`LinkFormatWrite::link`]. #[derive(Debug)] pub struct LinkAttributeWrite<'a, 'b, T: ?Sized>(&'b mut LinkFormatWrite<'a, T>); impl<'a, 'b, T: Write + ?Sized> LinkAttributeWrite<'a, 'b, T> { /// Prints just the key and an equals sign, prefixed with ';' fn internal_attr_key_eq(&mut self, key: &'static str) { debug_assert!(key .find(|c: char| c.is_ascii_whitespace() || c == '=') .is_none()); if self.0.error.is_none() { self.0.error = self.0.write.write_char(ATTR_SEPARATOR_CHAR).err(); } if self.0.error.is_none() { self.0.error = self.0.write.write_str(key).err(); } if self.0.error.is_none() { self.0.error = self.0.write.write_char('=').err(); } } /// Adds an attribute to the link, only quoting the value if it contains /// non-ascii-alphanumeric characters. pub fn attr(mut self, key: &'static str, value: &str) -> Self { if value.find(|c: char| !c.is_ascii_alphanumeric()).is_some() { return self.attr_quoted(key, value); } self.internal_attr_key_eq(key); if self.0.error.is_none() { self.0.error = self.0.write.write_str(value).err(); } self } /// Adds an attribute to the link that has u32 value. pub fn attr_u32(mut self, key: &'static str, value: u32) -> Self { self.internal_attr_key_eq(key); if self.0.error.is_none() { self.0.error = write!(self.0.write, "{}", value).err(); } self } /// Adds an attribute to the link that has u16 value. pub fn attr_u16(self, key: &'static str, value: u16) -> Self { self.attr_u32(key, value as u32) } /// Adds an attribute to the link, unconditionally quoting the value. pub fn attr_quoted(mut self, key: &'static str, value: &str) -> Self { self.internal_attr_key_eq(key); if self.0.error.is_none() { self.0.error = self.0.write.write_char('"').err(); } for c in value.chars() { if (c == '"' || c == '\\') && self.0.error.is_none() { self.0.error = self.0.write.write_char(QUOTE_ESCAPE_CHAR).err(); } if self.0.error.is_none() { self.0.error = self.0.write.write_char(c).err(); } } if self.0.error.is_none() { self.0.error = self.0.write.write_char('"').err(); } self } /// Consumes this [`LinkAttributeWrite`] instance, returning any error that /// might have occurred during writing. pub fn finish(self) -> Result<(), core::fmt::Error> { if let Some(e) = self.0.error { Err(e) } else { Ok(()) } } } #[cfg(test)] mod test { use super::*; #[test] fn link_format_write_1() { let mut buffer = String::new(); let mut write = LinkFormatWrite::new(&mut buffer); write .link(uri_ref!("/sensor/light")) .attr_quoted(LINK_ATTR_INTERFACE_DESCRIPTION, "sensor") .finish() .expect("Write link failed"); assert_eq!(write.finish(), Ok(())); assert_eq!(&buffer, r#"</sensor/light>;if="sensor""#); } #[test] fn link_format_write_2() { let mut buffer = String::new(); let mut write = LinkFormatWrite::new(&mut buffer); write .link(uri_ref!("/sensor/light")) .attr_quoted(LINK_ATTR_INTERFACE_DESCRIPTION, "sensor") .attr(LINK_ATTR_TITLE, "My Light") .finish() .expect("Write link failed"); write .link(uri_ref!("/sensor/temp")) .attr_quoted(LINK_ATTR_INTERFACE_DESCRIPTION, "sensor") .attr(LINK_ATTR_TITLE, "My Thermostat") .attr_u32(LINK_ATTR_VALUE, 20) .finish() .expect("Write link failed"); assert_eq!(write.finish(), Ok(())); assert_eq!(&buffer, r#"</sensor/light>;if="sensor";title="My Light",</sensor/temp>;if="sensor";title="My Thermostat";v=20"#); } #[test] fn unquote_1() { let unquote = Unquote::new(r#""sensor""#); assert_eq!(&unquote.to_string(), "sensor"); } #[test] fn unquote_2() { let unquote = Unquote::new("sensor"); assert_eq!(&unquote.to_string(), "sensor"); } #[test] fn unquote_3() { let unquote = Unquote::new(r#""the \"foo\" bar""#); assert_eq!(&unquote.to_string(), r#"the "foo" bar"#); } #[test] fn unquote_4() { let unquote = Unquote::new(r#""\"the foo bar\"""#); assert_eq!(&unquote.to_string(), r#""the foo bar""#); } #[test] fn unquote_5() { let unquote = Unquote::new(r#""the \\\"foo\\\" bar""#); assert_eq!(&unquote.to_string(), r#"the \"foo\" bar"#); } #[test] fn link_format_parser_1() { let link_format = r#"</sensors>;ct=40"#; let mut parser = LinkFormatParser::new(link_format); match parser.next() { Some(Ok((link, mut attr_iter))) => { eprintln!("attr_iter: {:?}", attr_iter); assert_eq!(link, "/sensors"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("ct", r#"40"#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } assert_eq!(parser.next(), None); } #[test] fn link_format_parser_2() { let link_format = r#" </sensors/temp>;if="sensor", </sensors/light>;if="sensor""#; let mut parser = LinkFormatParser::new(link_format); match parser.next() { Some(Ok((link, mut attr_iter))) => { eprintln!("attr_iter: {:?}", attr_iter); assert_eq!(link, "/sensors/temp"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("if", r#""sensor""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } match parser.next() { Some(Ok((link, mut attr_iter))) => { eprintln!("attr_iter: {:?}", attr_iter); assert_eq!(link, "/sensors/light"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("if", r#""sensor""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } assert_eq!(parser.next(), None); } #[test] fn link_format_parser_3() { let link_format = r#"</sensors>;ct=40;title="Sensor Index", </sensors/temp>;rt="temperature-c";if="sensor", </sensors/light>;rt="light-lux";if="sensor", <http://www.example.com/sensors/t123>;anchor="/sensors/temp" ;rel="describedby", </t>;anchor="/sensors/temp";rel="alternate""#; let mut parser = LinkFormatParser::new(link_format); match parser.next() { Some(Ok((link, mut attr_iter))) => { assert_eq!(link, "/sensors"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("ct", r#"40"#)) ); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("title", r#""Sensor Index""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } match parser.next() { Some(Ok((link, mut attr_iter))) => { assert_eq!(link, "/sensors/temp"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("rt", r#""temperature-c""#)) ); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("if", r#""sensor""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } match parser.next() { Some(Ok((link, mut attr_iter))) => { assert_eq!(link, "/sensors/light"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("rt", r#""light-lux""#)) ); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("if", r#""sensor""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } match parser.next() { Some(Ok((link, mut attr_iter))) => { assert_eq!(link, "http://www.example.com/sensors/t123"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("anchor", r#""/sensors/temp""#)) ); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("rel", r#""describedby""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } match parser.next() { Some(Ok((link, mut attr_iter))) => { assert_eq!(link, "/t"); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("anchor", r#""/sensors/temp""#)) ); assert_eq!( attr_iter.next().map(|attr| (attr.0, attr.1.into_raw_str())), Some(("rel", r#""alternate""#)) ); assert_eq!(attr_iter.next(), None); } x => { panic!("{:?}", x); } } assert_eq!(parser.next(), None); } }