Add new sorting: UpdateDate that sorts by meta.updated. (#1452)

* Add new sorting: UpdateDate that sorts by `meta.updated`.

* Use `max(created, updated)` for sort-by-update-date

This prevents created but never updated articles from appearing at the end/not
appearing at all.

components/front_matter/src/lib.rs

@@ -48,6 +48,8 @@ impl RawFrontMatter<'_> {
 pub enum SortBy {
     /// Most recent to oldest
     Date,
+    /// Most recent to oldest
+    UpdateDate,
     /// Sort by title
     Title,
     /// Lower weight comes first

components/front_matter/src/page.rs

@@ -20,6 +20,12 @@ pub struct PageFrontMatter {
     /// Updated date
     #[serde(default, deserialize_with = "from_toml_datetime")]
     pub updated: Option<String>,
+    /// Chrono converted update datatime
+    #[serde(default, skip_deserializing)]
+    pub updated_datetime: Option<NaiveDateTime>,
+    /// The converted update datetime into a (year, month, day) tuple
+    #[serde(default, skip_deserializing)]
+    pub updated_datetime_tuple: Option<(i32, u32, u32)>,
     /// Date if we want to order pages (ie blog post)
     #[serde(default, deserialize_with = "from_toml_datetime")]
     pub date: Option<String>,
@@ -107,6 +113,10 @@ impl PageFrontMatter {
     pub fn date_to_datetime(&mut self) {
         self.datetime = self.date.as_ref().map(|s| s.as_ref()).and_then(parse_datetime);
         self.datetime_tuple = self.datetime.map(|dt| (dt.year(), dt.month(), dt.day()));
+
+        self.updated_datetime = self.updated.as_ref().map(|s| s.as_ref()).and_then(parse_datetime);
+        self.updated_datetime_tuple =
+            self.updated_datetime.map(|dt| (dt.year(), dt.month(), dt.day()));
     }
 
     pub fn weight(&self) -> usize {
@@ -120,6 +130,8 @@ impl Default for PageFrontMatter {
             title: None,
             description: None,
             updated: None,
+            updated_datetime: None,
+            updated_datetime_tuple: None,
             date: None,
             datetime: None,
             datetime_tuple: None,

components/library/src/content/page.rs

@@ -60,6 +60,10 @@ pub struct Page {
     /// When <!-- more --> is found in the text, will take the content up to that part
     /// as summary
     pub summary: Option<String>,
+    /// The earlier updated page, for pages sorted by updated date
+    pub earlier_updated: Option<DefaultKey>,
+    /// The later updated page, for pages sorted by updated date
+    pub later_updated: Option<DefaultKey>,
     /// The earlier page, for pages sorted by date
     pub earlier: Option<DefaultKey>,
     /// The later page, for pages sorted by date

components/library/src/content/ser.rs

@@ -90,6 +90,8 @@ pub struct SerializingPage<'a> {
     lang: &'a str,
     lighter: Option<Box<SerializingPage<'a>>>,
     heavier: Option<Box<SerializingPage<'a>>>,
+    earlier_updated: Option<Box<SerializingPage<'a>>>,
+    later_updated: Option<Box<SerializingPage<'a>>>,
     earlier: Option<Box<SerializingPage<'a>>>,
     later: Option<Box<SerializingPage<'a>>>,
     title_prev: Option<Box<SerializingPage<'a>>>,
@@ -115,6 +117,12 @@ impl<'a> SerializingPage<'a> {
         let heavier = page
             .heavier
             .map(|k| Box::new(Self::from_page_basic(pages.get(k).unwrap(), Some(library))));
+        let earlier_updated = page
+            .earlier_updated
+            .map(|k| Box::new(Self::from_page_basic(pages.get(k).unwrap(), Some(library))));
+        let later_updated = page
+            .later_updated
+            .map(|k| Box::new(Self::from_page_basic(pages.get(k).unwrap(), Some(library))));
         let earlier = page
             .earlier
             .map(|k| Box::new(Self::from_page_basic(pages.get(k).unwrap(), Some(library))));
@@ -161,6 +169,8 @@ impl<'a> SerializingPage<'a> {
             lang: &page.lang,
             lighter,
             heavier,
+            earlier_updated,
+            later_updated,
             earlier,
             later,
             title_prev,
@@ -225,6 +235,8 @@ impl<'a> SerializingPage<'a> {
             lang: &page.lang,
             lighter: None,
             heavier: None,
+            earlier_updated: None,
+            later_updated: None,
             earlier: None,
             later: None,
             title_prev: None,

components/library/src/library.rs

@@ -3,13 +3,12 @@ use std::path::{Path, PathBuf};
 
 use slotmap::{DefaultKey, DenseSlotMap};
 
-use front_matter::SortBy;
-
 use crate::content::{Page, Section};
 use crate::sorting::{
     find_siblings, sort_pages_by_date, sort_pages_by_title, sort_pages_by_weight,
 };
 use config::Config;
+use front_matter::{PageFrontMatter, SortBy};
 
 // Like vec! but for HashSet
 macro_rules! set {
@@ -265,52 +264,47 @@ impl Library {
     /// Sort all sections pages according to sorting method given
     /// Pages that cannot be sorted are set to the section.ignored_pages instead
     pub fn sort_sections_pages(&mut self) {
+        fn get_data<'a, T>(
+            section: &'a Section,
+            pages: &'a DenseSlotMap<DefaultKey, Page>,
+            field: impl Fn(&'a PageFrontMatter) -> Option<T>,
+        ) -> Vec<(&'a DefaultKey, Option<T>, &'a str)> {
+            section
+                .pages
+                .iter()
+                .map(|k| {
+                    if let Some(page) = pages.get(*k) {
+                        (k, field(&page.meta), page.permalink.as_ref())
+                    } else {
+                        unreachable!("Sorting got an unknown page")
+                    }
+                })
+                .collect()
+        }
+
         let mut updates = HashMap::new();
         for (key, section) in &self.sections {
             let (sorted_pages, cannot_be_sorted_pages) = match section.meta.sort_by {
                 SortBy::None => continue,
                 SortBy::Date => {
-                    let data = section
+                    let data = get_data(section, &self.pages, |meta| meta.datetime);
-                        .pages
+
-                        .iter()
+                    sort_pages_by_date(data)
-                        .map(|k| {
+                }
-                            if let Some(page) = self.pages.get(*k) {
+                SortBy::UpdateDate => {
-                                (k, page.meta.datetime, page.permalink.as_ref())
+                    let data = get_data(section, &self.pages, |meta| {
-                            } else {
+                        std::cmp::max(meta.datetime, meta.updated_datetime)
-                                unreachable!("Sorting got an unknown page")
+                    });
-                            }
-                        })
-                        .collect();
 
                     sort_pages_by_date(data)
                 }
                 SortBy::Title => {
-                    let data = section
+                    let data = get_data(section, &self.pages, |meta| meta.title.as_deref());
-                        .pages
-                        .iter()
-                        .map(|k| {
-                            if let Some(page) = self.pages.get(*k) {
-                                (k, page.meta.title.as_deref(), page.permalink.as_ref())
-                            } else {
-                                unreachable!("Sorting got an unknown page")
-                            }
-                        })
-                        .collect();
 
                     sort_pages_by_title(data)
                 }
                 SortBy::Weight => {
-                    let data = section
+                    let data = get_data(section, &self.pages, |meta| meta.weight);
-                        .pages
-                        .iter()
-                        .map(|k| {
-                            if let Some(page) = self.pages.get(*k) {
-                                (k, page.meta.weight, page.permalink.as_ref())
-                            } else {
-                                unreachable!("Sorting got an unknown page")
-                            }
-                        })
-                        .collect();
 
                     sort_pages_by_weight(data)
                 }
@@ -329,6 +323,10 @@ impl Library {
                             page.earlier = val2;
                             page.later = val1;
                         }
+                        SortBy::UpdateDate => {
+                            page.earlier_updated = val2;
+                            page.later_updated = val1;
+                        }
                         SortBy::Title => {
                             page.title_prev = val1;
                             page.title_next = val2;