new: added sync indicator in follow mode

Cargo.toml

@@ -4,7 +4,7 @@ categories = ["command-line-utilities"]
 description = "Utility for viewing json-formatted log files."
 keywords = ["cli", "human", "log"]
 name = "hl"
-version = "0.20.0-beta.11"
+version = "0.20.0-beta.11.1"
 edition = "2021"
 build = "build.rs"
 

benches/theme.rs

@@ -97,6 +97,7 @@ fn benchmark(c: &mut Criterion) {
         }
         .into(),
         levels: HashMap::new(),
+        indicators: themecfg::IndicatorPack::default(),
     });
     let fields = vec![
         (b"key1", b"value1"),

etc/defaults/config.yaml

@@ -10,7 +10,16 @@ fields:
   # Configuration of the predefined set of fields.
   predefined:
     time:
-      names: [ts, TS, time, TIME, Time, _SOURCE_REALTIME_TIMESTAMP, __REALTIME_TIMESTAMP]
+      names:
+        [
+          ts,
+          TS,
+          time,
+          TIME,
+          Time,
+          _SOURCE_REALTIME_TIMESTAMP,
+          __REALTIME_TIMESTAMP,
+        ]
     logger:
       names: [logger, LOGGER, Logger]
     level:

etc/defaults/themes/universal.yaml

@@ -47,3 +47,12 @@ levels:
     level:
       foreground: bright-red
       modes: [reverse]
+indicators:
+  sync:
+    synced:
+      text: ' '
+    failed:
+      text: '!'
+      inner:
+        style:
+          foreground: 'yellow'

src/app.rs

@@ -427,6 +427,7 @@ impl App {
 
                 let mut window = BTreeMap::<Key,Line>::new();
                 let mut last_ts: Option<Timestamp> = None;
+                let mut prev_ts: Option<Timestamp> = None;
                 let mut mem_usage = 0;
                 let mem_limit = n * usize::from(self.options.buffer_size);
 
@@ -437,7 +438,14 @@ impl App {
                             break;
                         }
                         if let Some(entry) = window.pop_first() {
+                            let sync_indicator = if prev_ts.map(|ts| ts <= entry.0.0).unwrap_or(true) {
+                                &self.options.theme.indicators.sync.synced
+                            } else {
+                                &self.options.theme.indicators.sync.failed
+                            };
+                            prev_ts = Some(entry.0.0);
                             mem_usage -= entry.1.1.end - entry.1.1.start;
+                            output.write_all(sync_indicator.value.as_bytes())?;
                             output.write_all(&entry.1.0[entry.1.1.clone()])?;
                         }
                     }

src/theme.rs

@@ -31,13 +31,15 @@ pub trait StylingPush<B: Push<u8>> {
 pub struct Theme {
     packs: EnumMap<Level, StylePack>,
     default: StylePack,
+    pub indicators: IndicatorPack,
 }
 
 impl Theme {
     pub fn none() -> Self {
         Self {
             packs: EnumMap::default(),
             default: StylePack::default(),
+            indicators: IndicatorPack::default(),
         }
     }
 
@@ -81,7 +83,11 @@ impl<S: Borrow<themecfg::Theme>> From<S> for Theme {
         for (level, pack) in &s.levels {
             packs[*level] = StylePack::load(&s.elements.clone().merged(pack.clone()));
         }
-        Self { default, packs }
+        Self {
+            default,
+            packs,
+            indicators: IndicatorPack::from(&s.indicators),
+        }
     }
 }
 
@@ -96,6 +102,17 @@ impl Style {
         buf.extend_from_slice(self.0.data())
     }
 
+    #[inline(always)]
+    pub fn with<B: Push<u8>, F: FnOnce(&mut B)>(&self, buf: &mut B, f: F) {
+        if self.0.data().is_empty() {
+            f(buf)
+        } else {
+            buf.extend_from_slice(self.0.data());
+            f(buf);
+            buf.extend_from_slice(Self::reset().0.data());
+        }
+    }
+
     pub fn reset() -> Self {
         Sequence::reset().into()
     }
@@ -262,6 +279,67 @@ impl StylePack {
 
 // ---
 
+#[derive(Default)]
+pub struct IndicatorPack {
+    pub sync: SyncIndicatorPack,
+}
+
+impl From<&themecfg::IndicatorPack> for IndicatorPack {
+    fn from(indicator: &themecfg::IndicatorPack) -> Self {
+        Self {
+            sync: SyncIndicatorPack::from(&indicator.sync),
+        }
+    }
+}
+
+// ---
+
+#[derive(Default)]
+pub struct SyncIndicatorPack {
+    pub synced: Indicator,
+    pub failed: Indicator,
+}
+
+impl From<&themecfg::SyncIndicatorPack> for SyncIndicatorPack {
+    fn from(indicator: &themecfg::SyncIndicatorPack) -> Self {
+        Self {
+            synced: Indicator::from(&indicator.synced),
+            failed: Indicator::from(&indicator.failed),
+        }
+    }
+}
+
+// ---
+
+#[derive(Default)]
+pub struct Indicator {
+    pub value: String,
+}
+
+impl From<&themecfg::Indicator> for Indicator {
+    fn from(indicator: &themecfg::Indicator) -> Self {
+        let mut buf = Vec::new();
+        let os = Style::from(&indicator.outer.style);
+        let is = Style::from(&indicator.inner.style);
+        os.apply(&mut buf);
+        os.with(&mut buf, |buf| {
+            buf.extend(indicator.outer.prefix.as_bytes());
+            is.with(buf, |buf| {
+                buf.extend(indicator.inner.prefix.as_bytes());
+                buf.extend(indicator.text.as_bytes());
+                buf.extend(indicator.outer.prefix.as_bytes());
+            });
+            buf.extend(indicator.outer.suffix.as_bytes());
+        });
+
+        Self {
+            value: String::from_utf8(buf).unwrap(),
+        }
+    }
+}
+
+// ---
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/themecfg.rs

@@ -25,6 +25,7 @@ use crate::{error::*, level::Level};
 pub struct Theme {
     pub elements: StylePack,
     pub levels: HashMap<Level, StylePack>,
+    pub indicators: IndicatorPack,
 }
 
 impl Theme {
@@ -308,6 +309,71 @@ impl fmt::Display for RGB {
 
 // ---
 
+#[derive(Clone, Debug, Default, Deserialize)]
+#[serde(rename_all = "kebab-case")]
+#[serde(default)]
+pub struct IndicatorPack {
+    pub sync: SyncIndicatorPack,
+}
+
+// ---
+
+#[derive(Clone, Debug, Deserialize)]
+#[serde(rename_all = "kebab-case")]
+pub struct SyncIndicatorPack {
+    pub synced: Indicator,
+    pub failed: Indicator,
+}
+
+impl Default for SyncIndicatorPack {
+    fn default() -> Self {
+        Self {
+            synced: Indicator {
+                outer: IndicatorStyle::default(),
+                inner: IndicatorStyle::default(),
+                text: " ".into(),
+            },
+            failed: Indicator {
+                outer: IndicatorStyle::default(),
+                inner: IndicatorStyle {
+                    prefix: String::default(),
+                    suffix: String::default(),
+                    style: Style {
+                        modes: Vec::default(),
+                        background: None,
+                        foreground: Some(Color::Plain(PlainColor::Yellow)),
+                    },
+                },
+                text: "!".into(),
+            },
+        }
+    }
+}
+
+// ---
+
+#[derive(Clone, Debug, Default, Deserialize)]
+#[serde(rename_all = "kebab-case")]
+#[serde(default)]
+pub struct Indicator {
+    pub outer: IndicatorStyle,
+    pub inner: IndicatorStyle,
+    pub text: String,
+}
+
+// ---
+
+#[derive(Clone, Debug, Default, Deserialize)]
+#[serde(rename_all = "kebab-case")]
+#[serde(default)]
+pub struct IndicatorStyle {
+    pub prefix: String,
+    pub suffix: String,
+    pub style: Style,
+}
+
+// ---
+
 #[derive(RustEmbed)]
 #[folder = "etc/defaults/themes/"]
 struct Assets;