docx-rs/docx-core/src/xml_json/mod.rs

281 lines
8.7 KiB
Rust

// Licensed under either of
//
// Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
// MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
// at your option.
//
// Contribution
// Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.
// use serde::Serialize;
use serde::Serialize;
use std::fmt;
use std::io::prelude::*;
use std::io::Cursor;
use std::str::FromStr;
use xml::attribute::OwnedAttribute;
use xml::name::OwnedName;
use xml::namespace::{self, Namespace};
use xml::reader::{EventReader, XmlEvent};
/// An XML Document
#[derive(Debug, Clone)]
pub struct XmlDocument {
/// Data contained within the parsed XML Document
pub data: Vec<XmlData>,
}
// Print as JSON
impl fmt::Display for XmlDocument {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut s = String::new();
for d in self.data.iter() {
s = format!("{}{}", s, d);
}
s.fmt(f)
}
}
/// An XML Tag
///
/// For exammple:
///
/// ```XML
/// <foo bar="baz">
/// test text
/// <sub></sub>
/// </foo>
/// ```
#[derive(Debug, Clone, Serialize)]
pub struct XmlData {
/// Name of the tag (i.e. "foo")
pub name: String,
/// Key-value pairs of the attributes (i.e. ("bar", "baz"))
pub attributes: Vec<(String, String)>,
/// Data (i.e. "test text")
pub data: Option<String>,
/// Sub elements (i.e. an XML element of "sub")
pub children: Vec<XmlData>,
}
// Generate indentation
fn indent(size: usize) -> String {
const INDENT: &str = " ";
(0..size)
.map(|_| INDENT)
.fold(String::with_capacity(size * INDENT.len()), |r, s| r + s)
}
// Get the attributes as a string
fn attributes_to_string(attributes: &[(String, String)]) -> String {
attributes
.iter()
.fold(String::new(), |acc, &(ref k, ref v)| {
format!("{} {}=\"{}\"", acc, k, v)
})
}
// Format the XML data as a string
fn format(data: &XmlData, depth: usize) -> String {
let sub = if data.children.is_empty() {
String::new()
} else {
let mut sub = "\n".to_string();
for elmt in data.children.iter() {
sub = format!("{}{}", sub, format(elmt, depth + 1));
}
sub
};
let indt = indent(depth);
let fmt_data = if let Some(ref d) = data.data {
format!("\n{}{}", indent(depth + 1), d)
} else {
"".to_string()
};
format!(
"{}<{}{}>{}{}\n{}</{}>\n",
indt,
data.name,
attributes_to_string(&data.attributes),
fmt_data,
sub,
indt,
data.name
)
}
impl fmt::Display for XmlData {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", format(self, 0))
}
}
// Get the XML atributes as a string
fn map_owned_attributes(attrs: Vec<xml::attribute::OwnedAttribute>) -> Vec<(String, String)> {
attrs
.into_iter()
.map(|attr| {
let fmt_name = if attr.name.prefix.is_some() {
if !attr.name.local_name.is_empty() {
format!("{}:{}", attr.name.prefix.unwrap(), attr.name.local_name)
} else {
attr.name.prefix.unwrap()
}
} else {
attr.name.local_name.clone()
};
(fmt_name, attr.value)
})
.collect()
}
// Parse the data
fn parse(
mut data: Vec<XmlEvent>,
current: Option<XmlData>,
mut current_vec: Vec<XmlData>,
trim: bool,
current_namespace: Namespace,
) -> Result<(Vec<XmlData>, Vec<XmlEvent>), String> {
if let Some(elmt) = data.pop() {
match elmt {
XmlEvent::StartElement {
name,
attributes,
namespace,
} => {
let fmt_name = if name.prefix.is_some() {
if !name.local_name.is_empty() {
format!("{}:{}", name.prefix.unwrap(), name.local_name)
} else {
name.prefix.unwrap()
}
} else {
name.local_name
};
let attributes = if namespace == current_namespace {
attributes
} else {
let mut attributes = attributes;
let n = namespace.clone();
let ns = n
.into_iter()
.filter(|&(_k, v)| {
(v != namespace::NS_EMPTY_URI)
&& (v != namespace::NS_XMLNS_URI)
&& (v != namespace::NS_XML_URI)
})
.map(|(k, v)| OwnedAttribute {
name: OwnedName {
local_name: k.to_string(),
namespace: if v == namespace::NS_NO_PREFIX {
None
} else {
Some(v.to_string())
},
prefix: Some("xmlns".to_string()),
},
value: v.to_string(),
});
attributes.extend(ns);
attributes
};
let inner = XmlData {
name: fmt_name,
attributes: map_owned_attributes(attributes),
data: None,
children: Vec::new(),
};
let (inner, rest) = parse(data, Some(inner), Vec::new(), trim, namespace.clone())?;
if let Some(mut crnt) = current {
crnt.children.extend(inner);
parse(rest, Some(crnt), current_vec, trim, namespace)
} else {
current_vec.extend(inner);
parse(rest, None, current_vec, trim, namespace)
}
}
XmlEvent::Characters(chr) => {
let chr = if trim { chr.trim().to_string() } else { chr };
if let Some(mut crnt) = current {
crnt.data = Some(chr);
parse(data, Some(crnt), current_vec, trim, current_namespace)
} else {
Err("Invalid form of XML doc".to_string())
}
}
XmlEvent::EndElement { name } => {
let fmt_name = if name.prefix.is_some() {
if !name.local_name.is_empty() {
format!("{}:{}", name.prefix.unwrap(), name.local_name)
} else {
name.prefix.unwrap()
}
} else {
name.local_name.clone()
};
if let Some(crnt) = current {
if crnt.name == fmt_name {
current_vec.push(crnt);
Ok((current_vec, data))
} else {
Err(format!(
"Invalid end tag: expected {}, got {}",
crnt.name, name.local_name
))
}
} else {
Err(format!("Invalid end tag: {}", name.local_name))
}
}
_ => parse(data, current, current_vec, trim, current_namespace),
}
} else if let Some(_current) = current {
Err("Invalid end tag".to_string())
} else {
Ok((current_vec, Vec::new()))
}
}
impl XmlDocument {
pub fn from_reader<R>(source: R, trim: bool) -> Result<Self, ParseXmlError>
where
R: Read,
{
let parser = EventReader::new(source);
let mut events: Vec<XmlEvent> = parser.into_iter().map(|x| x.unwrap()).collect();
events.reverse();
parse(events, None, Vec::new(), trim, Namespace::empty())
.map(|(data, _)| XmlDocument { data })
.map_err(ParseXmlError)
}
}
/// Error when parsing XML
#[derive(Debug, Clone, PartialEq)]
pub struct ParseXmlError(String);
impl fmt::Display for ParseXmlError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "Coult not parse string to XML: {}", self.0)
}
}
// Generate an XML document from a string
impl FromStr for XmlDocument {
type Err = ParseXmlError;
fn from_str(s: &str) -> Result<XmlDocument, ParseXmlError> {
XmlDocument::from_reader(Cursor::new(s.to_string().into_bytes()), true)
}
}