zola/components/utils/src/de.rs
Kevin Ottens 4754cb5792 Yaml frontmatter (#990)
* Accept dates presented as strings

Still, if we find a string we involve the TOML parser to make sure the
content of said string would be a correct TOML date. In a pure TOML
world this isn't exactly relevant, but this will come in handy when
using a YAML deserializer.

Signed-off-by: Kevin Ottens <ervin@ipsquad.net>

* Add serde_yaml and test-case dependencies

This will be necessary for the YAML frontmatter handling and
corresponding unit tests.

Signed-off-by: Kevin Ottens <ervin@ipsquad.net>

* Add YAML front matter handling

Signed-off-by: Kevin Ottens <ervin@ipsquad.net>

* Switch RawFrontMatter enum to wrap &str instead of String

Signed-off-by: Kevin Ottens <ervin@ipsquad.net>

* Update the documentation to mention YAML frontmatter

This is just a light update on purpose. There would be no point in
pushing YAML too much, this is mainly here to help people with a backlog
of posts to transition.

Signed-off-by: Kevin Ottens <ervin@ipsquad.net>
2020-12-14 20:43:31 +01:00

83 lines
2.4 KiB
Rust

use serde::{Deserialize, Deserializer};
use serde_derive::Deserialize;
use tera::{Map, Value};
/// Used as an attribute when we want to convert from TOML to a string date
/// If a TOML datetime isn't present, it will accept a string and push it through
/// TOML's date time parser to ensure only valid dates are accepted.
/// Inspired by this proposal: https://github.com/alexcrichton/toml-rs/issues/269
pub fn from_toml_datetime<'de, D>(deserializer: D) -> Result<Option<String>, D::Error>
where
D: Deserializer<'de>,
{
use serde::de::Error;
use std::str::FromStr;
#[derive(Deserialize)]
#[serde(untagged)]
enum MaybeDatetime {
Datetime(toml::value::Datetime),
String(String),
}
match MaybeDatetime::deserialize(deserializer)? {
MaybeDatetime::Datetime(d) => Ok(Some(d.to_string())),
MaybeDatetime::String(s) => match toml::value::Datetime::from_str(&s) {
Ok(d) => Ok(Some(d.to_string())),
Err(e) => Err(D::Error::custom(e)),
},
}
}
/// Returns key/value for a converted date from TOML.
/// If the table itself is the TOML struct, only return its value without the key
fn convert_toml_date(table: Map<String, Value>) -> Value {
let mut new = Map::new();
for (k, v) in table {
if k == "$__toml_private_datetime" {
return v;
}
match v {
Value::Object(o) => {
new.insert(k, convert_toml_date(o));
}
_ => {
new.insert(k, v);
}
}
}
Value::Object(new)
}
/// TOML datetimes will be serialized as a struct but we want the
/// stringified version for json, otherwise they are going to be weird
pub fn fix_toml_dates(table: Map<String, Value>) -> Value {
let mut new = Map::new();
for (key, value) in table {
match value {
Value::Object(o) => {
new.insert(key, convert_toml_date(o));
}
Value::Array(arr) => {
let mut new_arr = Vec::with_capacity(arr.len());
for v in arr {
match v {
Value::Object(o) => new_arr.push(fix_toml_dates(o)),
_ => new_arr.push(v),
};
}
new.insert(key, Value::Array(new_arr));
}
_ => {
new.insert(key, value);
}
}
}
Value::Object(new)
}