Add last/next crawl times to feeds, improve local time rendering

frontend/js/localTimeController.ts

@@ -1,20 +1,77 @@
+// This file is used to convert UTC timestamps from the server to human-readable local time in the browser.
+//
+// Usage: Add a time element with a `datetime` attribute and a `data-local-time` attribute to the HTML.
+//
+// `data-local-time` can be either 'relative' or 'date'.
+// 'relative' will show the time in a human-readable format, e.g. "2 hours from now".
+// 'date' will show the date in a human-readable format, e.g. "January 1, 2022".
+// Any other value will be ignored and time will be shown as-is from the server as a UTC timestamp.
+
+function pluralize(count: number, singular: string, plural: string): string {
+  return count === 1 ? singular : plural;
+}
+
+function formatRelativeTime(utcTime: Date): string {
+  const now = new Date();
+  const diffInSeconds = (utcTime.getTime() - now.getTime()) / 1000;
+
+  if (diffInSeconds < -86400) {
+    const days = Math.round(Math.abs(diffInSeconds) / 86400);
+    return `${days} ${pluralize(days, 'day', 'days')} ago`;
+  } else if (diffInSeconds < -3600) {
+    const hours = Math.round(Math.abs(diffInSeconds) / 3600);
+    return `${hours} ${pluralize(Math.abs(hours), 'hour', 'hours')} ago`;
+  } else if (diffInSeconds < -60) {
+    const minutes = Math.round(Math.abs(diffInSeconds) / 60);
+    return `${minutes} ${pluralize(minutes, 'minute', 'minutes')} ago`;
+  } else if (diffInSeconds < 0) {
+    const seconds = Math.abs(diffInSeconds);
+    return `${seconds} ${pluralize(seconds, 'second', 'seconds')} ago`;
+  } else if (diffInSeconds < 60) {
+    return `${diffInSeconds} ${pluralize(
+      diffInSeconds,
+      'second',
+      'seconds'
+    )} from now`;
+  } else if (diffInSeconds < 3600) {
+    const minutes = Math.round(diffInSeconds / 60);
+    return `${minutes} ${pluralize(minutes, 'minute', 'minutes')} from now`;
+  } else if (diffInSeconds < 86400) {
+    const hours = Math.round(diffInSeconds / 3600);
+    return `${hours} ${pluralize(hours, 'hour', 'hours')} from now`;
+  } else {
+    const days = Math.round(diffInSeconds / 86400);
+    return `${days} ${pluralize(days, 'day', 'days')} from now`;
+  }
+}
+
 function convertTimeElements(): void {
-  const timeElements = document.querySelectorAll('time.local-time');
+  const timeElements = document.querySelectorAll('time[data-local-time]');
   timeElements.forEach((element) => {
     const utcString = element.getAttribute('datetime');
     if (utcString !== null) {
       const utcTime = new Date(utcString);
-      element.textContent = utcTime.toLocaleDateString(
-        window.navigator.language,
-        {
-          year: 'numeric',
-          month: 'long',
-          day: 'numeric',
-        }
-      );
+      const localTimeType = element.getAttribute('data-local-time');
+      if (localTimeType === 'relative') {
+        element.textContent = formatRelativeTime(utcTime);
+      } else if (localTimeType === 'date') {
+        element.textContent = utcTime.toLocaleDateString(
+          window.navigator.language,
+          {
+            year: 'numeric',
+            month: 'long',
+            day: 'numeric',
+          }
+        );
+      } else {
+        console.error(
+          'Unrecognized data-local-time attribute value on time[data-local-time] element. Local time cannot be displayed.',
+          element
+        );
+      }
     } else {
       console.error(
-        'Missing datetime attribute on time.local-time element',
+        'Missing datetime attribute on time[data-local-time] element',
         element
       );
     }

src/handlers/entry.rs

@@ -11,6 +11,7 @@ use crate::error::Result;
 use crate::htmx::HXTarget;
 use crate::models::entry::Entry;
 use crate::partials::layout::Layout;
+use crate::partials::time::date_time;
 use crate::uuid::Base62Uuid;
 
 pub async fn get(
@@ -24,9 +25,6 @@ pub async fn get(
     let content_dir = std::path::Path::new(&config.content_dir);
     let content_path = content_dir.join(format!("{}.html", entry.entry_id));
     let title = entry.title.unwrap_or_else(|| "Untitled Entry".to_string());
-    let published_at = entry
-        .published_at
-        .to_rfc3339_opts(chrono::SecondsFormat::Millis, true);
     let content = fs::read_to_string(content_path).unwrap_or_else(|_| "No content".to_string());
     Ok(layout
         .with_subtitle(&title)
@@ -41,9 +39,7 @@ pub async fn get(
                 div {
                     span class="text-sm text-gray-600" {
                         strong { "Published: " }
-                        time datetime=(published_at) class="local-time" {
-                            (published_at)
-                        }
+                        (date_time(entry.published_at))
                     }
                 }
                 (PreEscaped(content))

src/main.rs

@@ -3,7 +3,6 @@ use std::{collections::HashMap, net::SocketAddr, path::Path, sync::Arc};
 use anyhow::Result;
 use axum::{
     error_handling::HandleErrorLayer,
-    response::Response,
     routing::{get, post},
     BoxError, Router,
 };

src/models/feed.rs

@@ -127,6 +127,12 @@ pub struct GetFeedsOptions {
 }
 
 impl Feed {
+    pub fn next_crawl_time(&self) -> Option<DateTime<Utc>> {
+        self.last_crawled_at.map(|last_crawled_at| {
+            last_crawled_at + chrono::Duration::minutes(self.crawl_interval_minutes as i64)
+        })
+    }
+
     pub async fn get(db: impl Executor<'_, Database = Postgres>, feed_id: Uuid) -> Result<Feed> {
         sqlx::query_as!(
             Feed,

src/partials/feed_link.rs

@@ -2,12 +2,14 @@ use maud::{html, Markup};
 
 use crate::models::feed::Feed;
 use crate::partials::link::{link, LinkProps};
+use crate::partials::time::relative_time;
 use crate::uuid::Base62Uuid;
 
 pub struct FeedLink<'a> {
     pub feed: &'a Feed,
     pub pending_crawl: bool,
     pub reset_htmx_target: bool,
+    pub show_next_crawl_time: bool,
 }
 
 impl FeedLink<'_> {
@@ -16,6 +18,7 @@ impl FeedLink<'_> {
             feed,
             pending_crawl: false,
             reset_htmx_target: false,
+            show_next_crawl_time: false,
         }
     }
 
@@ -29,6 +32,11 @@ impl FeedLink<'_> {
         self
     }
 
+    pub fn show_next_crawl_time(&mut self) -> &mut Self {
+        self.show_next_crawl_time = true;
+        self
+    }
+
     pub fn render(&self) -> Markup {
         let title = self.feed.title.clone().unwrap_or_else(|| {
             if self.pending_crawl {
@@ -39,7 +47,21 @@ impl FeedLink<'_> {
         });
         let feed_url = format!("/feed/{}", Base62Uuid::from(self.feed.feed_id));
         html! {
-            (link(LinkProps { destination: &feed_url, title: &title, reset_htmx_target: self.reset_htmx_target }))
+            div class="flex flex-row gap-4 items-baseline" {
+                (link(LinkProps { destination: &feed_url, title: &title, reset_htmx_target: self.reset_htmx_target }))
+                @if let Some(last_crawl) = self.feed.last_crawled_at {
+                    span class="text-sm text-gray-600" {
+                        span class="font-semibold" { "last crawl: " }
+                        (relative_time(last_crawl))
+                    }
+                }
+                @if let Some(next_crawl) = self.feed.next_crawl_time() {
+                    span class="text-sm text-gray-600" {
+                        span class="font-semibold" { "next crawl: " }
+                        (relative_time(next_crawl))
+                    }
+                }
+            }
         }
     }
 }

src/partials/mod.rs

@@ -13,4 +13,5 @@ pub mod login_form;
 pub mod opml_import_form;
 pub mod register_form;
 pub mod reset_password_form;
+pub mod time;
 pub mod user_name;

src/partials/opml_import_form.rs

@@ -1,4 +1,4 @@
-use maud::{html, Markup, PreEscaped};
+use maud::{html, Markup};
 
 pub fn opml_import_form() -> Markup {
     html! {

src/partials/time.rs

@@ -0,0 +1,59 @@
+use std::fmt;
+
+use chrono::{DateTime, Utc};
+use maud::{html, Markup};
+
+use crate::utils::FormattedUtcTimestamp;
+
+#[derive(Debug)]
+pub enum LocalTimeType {
+    Date,
+    Relative,
+}
+
+impl fmt::Display for LocalTimeType {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            LocalTimeType::Date => write!(f, "date"),
+            LocalTimeType::Relative => write!(f, "relative"),
+        }
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct TimeProps {
+    pub timestamp: DateTime<Utc>,
+    pub local_time_type: Option<LocalTimeType>,
+}
+
+pub fn time(
+    TimeProps {
+        timestamp,
+        local_time_type,
+    }: TimeProps,
+) -> Markup {
+    let time = FormattedUtcTimestamp::from(timestamp);
+    html! {
+        time
+            datetime=(time.rfc3339)
+            data-local-time=(local_time_type.unwrap_or(LocalTimeType::Date))
+            title=(time.human_readable)
+        {
+            (time.rfc3339)
+        }
+    }
+}
+
+pub fn date_time(timestamp: DateTime<Utc>) -> Markup {
+    time(TimeProps {
+        timestamp,
+        local_time_type: Some(LocalTimeType::Date),
+    })
+}
+
+pub fn relative_time(timestamp: DateTime<Utc>) -> Markup {
+    time(TimeProps {
+        timestamp,
+        local_time_type: Some(LocalTimeType::Relative),
+    })
+}

src/utils.rs

@@ -1,3 +1,4 @@
+use chrono::{DateTime, SecondsFormat, Utc};
 use url::Url;
 
 pub fn get_domain(url: &str) -> Option<String> {
@@ -12,3 +13,17 @@ pub fn get_domain(url: &str) -> Option<String> {
             }
         })
 }
+
+pub struct FormattedUtcTimestamp {
+    pub rfc3339: String,
+    pub human_readable: String,
+}
+
+impl From<DateTime<Utc>> for FormattedUtcTimestamp {
+    fn from(dt: DateTime<Utc>) -> Self {
+        FormattedUtcTimestamp {
+            rfc3339: dt.to_rfc3339_opts(SecondsFormat::Millis, true),
+            human_readable: dt.format("%Y-%m-%d %H:%M:%S %Z").to_string(),
+        }
+    }
+}