Add a table helper type to make it easier to display data. Migrate the flows view to the new system.

src/rust/lqtop/src/widgets/mod.rs

@@ -1,4 +1,5 @@
 mod stats_ringbuffer;
+mod table_helper;
 mod cpu;
 pub use cpu::cpu_display;
 mod network_sparkline;

src/rust/lqtop/src/widgets/table_helper.rs

@@ -0,0 +1,67 @@
+use ratatui::{style::{Color, Style}, text::Text, widgets::{Block, Borders, Cell, Row, Table}};
+
+/// A helper for building Ratatui tables
+pub struct TableHelper<const N_COLS: usize> {
+    headers: [String; N_COLS],
+    rows: Vec<[String; N_COLS]>,
+}
+
+impl <const N: usize> TableHelper<N> {
+    pub fn new<S: ToString>(raw_headers: [S; N]) -> Self {
+        const ARRAY_REPEAT_VALUE: String = String::new();
+        let mut headers = [ARRAY_REPEAT_VALUE; N];
+        for i in 0..N {
+            headers[i] = raw_headers[i].to_string();
+        }
+        
+        let headers = headers.try_into().unwrap();
+        Self {
+            headers,
+            rows: Vec::new(),
+        }
+    }
+
+    pub fn add_row(&mut self, row: [String; N]) {
+        self.rows.push(row);
+    }
+
+    pub fn to_table(&self) -> Table {
+        let header_cells: Vec<_> = self.headers.
+            iter()
+            .map(|h| Cell::from(Text::from(h.clone())))
+            .collect();
+
+        let rows: Vec<_> = self.rows
+            .iter()
+            .map(|row| {
+                let cells = row.iter()
+                    .map(|cell| Cell::from(Text::from(cell.clone())))
+                    .collect::<Vec<Cell>>();
+                Row::new(cells)
+            })
+            .collect();
+
+        let mut widths = [0u16; N];
+        for (i, heading) in self.headers.iter().enumerate() {
+            widths[i] = (heading.len() + 2) as u16;
+        }
+        for row in self.rows.iter() {
+            for (j, cell) in row.iter().enumerate() {
+                if cell.len() + 2 > widths[j] as usize {
+                    widths[j] = (cell.len() + 2) as u16;
+                }
+            }
+        }
+
+        Table::new(rows, widths)
+            .header(Row::new(header_cells).style(Style::default().fg(Color::White).bg(Color::Blue)))
+    }
+
+    pub fn to_block(&self) -> Table {
+        let block = Block::default()
+            //.title("Top Downloaders")
+            .borders(Borders::NONE)
+            .style(Style::default().fg(Color::Green));
+        self.to_table().block(block)
+    }
+}

src/rust/lqtop/src/widgets/top_flows.rs

@@ -1,7 +1,7 @@
-use super::TopWidget;
+use super::{table_helper::TableHelper, TopWidget};
 use lqos_bus::{BusResponse, FlowbeeSummaryData};
 use lqos_utils::packet_scale::scale_bits;
-use ratatui::{prelude::*, widgets::*};
+use ratatui::prelude::*;
 
 pub struct TopFlows {
     bus_link: tokio::sync::mpsc::Sender<crate::bus::BusMessage>,
@@ -37,52 +37,29 @@ impl TopWidget for TopFlows {
     }
 
     fn render_to_frame(&mut self, frame: &mut Frame) {
-        let block = Block::default()
-            //.title("Top Downloaders")
-            .borders(Borders::NONE)
-            .style(Style::default().fg(Color::Green));
-
-        let mut rows = Vec::new();
-
+        let mut t = TableHelper::new([
+            "Src IP",
+            "Dst IP",
+            "Type",
+            "Upload",
+            "Download",
+            "Retransmits",
+            "RTT (ms)",
+            "ASN",
+        ]);
         for flow in self.flows.iter() {
-            rows.push(
-                Row::new(vec![
-                    Cell::from(Text::from(flow.local_ip.to_string())),
-                    Cell::from(Text::from(flow.remote_ip.to_string())),
-                    Cell::from(Text::from(flow.analysis.to_string())),
-                    Cell::from(Text::from(scale_bits(flow.bytes_sent[0]))),
-                    Cell::from(Text::from(scale_bits(flow.bytes_sent[1]))),
-                    Cell::from(Text::from(format!(
-                        "{}/{}",
-                        flow.tcp_retransmits[0], flow.tcp_retransmits[1]
-                    ))),
-                    Cell::from(Text::from(format!(
-                        "{:.1}/{:.1}",
-                        flow.rtt_nanos[0] as f64 / 1000000.,
-                        flow.tcp_retransmits[1] as f64 / 1000000.
-                    ))),
-                    Cell::from(Text::from(flow.remote_asn_name.to_string())),
-                ])
-                .style(style::Style::default().fg(Color::White)),
-            );
+            t.add_row([
+                flow.local_ip.to_string(),
+                flow.remote_ip.to_string(),
+                flow.analysis.to_string(),
+                scale_bits(flow.bytes_sent[0]),
+                scale_bits(flow.bytes_sent[1]),
+                format!("{}/{}", flow.tcp_retransmits[0], flow.tcp_retransmits[1]),
+                format!("{:.1}/{:.1}", flow.rtt_nanos[0] as f64 / 1000000., flow.tcp_retransmits[1] as f64 / 1000000.),
+                flow.remote_asn_name.to_string(),
+            ]);
         }
-
-        let header = Row::new(vec![
-            Cell::from(Text::from("Src IP")),
-            Cell::from(Text::from("Dst IP")),
-            Cell::from(Text::from("Type")),
-            Cell::from(Text::from("Upload")),
-            Cell::from(Text::from("Download")),
-            Cell::from(Text::from("Retransmits")),
-            Cell::from(Text::from("RTT (ms)")),
-            Cell::from(Text::from("ASN")),
-        ])
-        .style(style::Style::default().fg(Color::Yellow).bg(Color::Blue));
-
-        let table = Table::new(rows, [15, 15, 20, 14, 14, 10, 15, 20])
-            .block(block)
-            .header(header);
-
+        let table = t.to_block();
         frame.render_widget(table, self.size);
     }
 }