A progress bar will be shown while the remote resource is being read

daze.go

@@ -29,6 +29,7 @@ import (
 
 	"github.com/mohanson/daze/lib/doa"
 	"github.com/mohanson/daze/lib/lru"
+	"github.com/mohanson/daze/lib/pretty"
 )
 
 // ============================================================================
@@ -1052,6 +1053,24 @@ func (r *RandomReader) Read(p []byte) (int, error) {
 	return len(p), nil
 }
 
+// The PrettyReader struct represents a custom reader that keeps track of read bytes and prints progress.
+type PrettyReader struct {
+	E uint64    // Total number of bytes read so far
+	F uint64    // Total capacity of the input stream
+	R io.Reader // The underlying reader that this object wraps around
+}
+
+// The Read method reads data from the wrapped reader and prints progress updates.
+func (r *PrettyReader) Read(p []byte) (int, error) {
+	if r.E == 0 {
+		pretty.PrintProgress(0)
+	}
+	n, err := r.R.Read(p)
+	r.E += uint64(n)
+	pretty.PrintProgress(float64(r.E) / float64(r.F))
+	return n, err
+}
+
 // Salt converts the stupid password passed in by the user to 32-sized byte array.
 func Salt(s string) []byte {
 	h := sha256.Sum256([]byte(s))
@@ -1075,8 +1094,14 @@ func Salt(s string) []byte {
 // LoadApnic loads remote resource. APNIC is the Regional Internet Registry administering IP addresses for the Asia
 // Pacific.
 func LoadApnic() map[string][]*net.IPNet {
-	log.Println("main: load apnic data from http://ftp.apnic.net/apnic/stats/apnic/delegated-apnic-latest")
-	f := doa.Try(OpenFile("http://ftp.apnic.net/apnic/stats/apnic/delegated-apnic-latest"))
+	url := "http://ftp.apnic.net/apnic/stats/apnic/delegated-apnic-latest"
+	log.Println("main: load apnic data from", url)
+	rep := doa.Try(http.Get(url))
+	f := &ReadWriteCloser{
+		Reader: &PrettyReader{0, uint64(rep.ContentLength), rep.Body},
+		Writer: nil,
+		Closer: rep.Body,
+	}
 	defer f.Close()
 	r := map[string][]*net.IPNet{}
 	s := bufio.NewScanner(f)

lib/pretty/README.md

@@ -0,0 +1,29 @@
+# Pretty
+
+Utilities to prettify console output.
+
+**Progress**
+
+```
+$ go run cmd/progress/main.go
+
+2025/03/12 09:53:42 pretty: [=========================>                   ]  59%
+```
+
+
+
+**Table**
+
+```
+$ go run cmd/table/main.go
+
+2025/03/12 09:51:57 pretty: City name Area Population Annual Rainfall
+2025/03/12 09:51:57 pretty: -----------------------------------------
+2025/03/12 09:51:57 pretty:  Adelaide 1295    1158259           600.5
+2025/03/12 09:51:57 pretty:  Brisbane 5905    1857594          1146.4
+2025/03/12 09:51:57 pretty:    Darwin  112     120900          1714.7
+2025/03/12 09:51:57 pretty:    Hobart 1357     205556           619.5
+2025/03/12 09:51:57 pretty: Melbourne 1566    3806092           646.9
+2025/03/12 09:51:57 pretty:     Perth 5386    1554769           869.4
+2025/03/12 09:51:57 pretty:    Sydney 2058    4336374          1214.8
+```

lib/pretty/cmd/progress/main.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"time"
+
+	"github.com/mohanson/daze/lib/pretty"
+)
+
+func main() {
+	pretty.PrintProgress(0)
+	for i := range 100 {
+		time.Sleep(time.Millisecond * 16)
+		pretty.PrintProgress(float64(i+1) / 100)
+	}
+	pretty.PrintProgress(1)
+}

lib/pretty/cmd/table/main.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"github.com/mohanson/daze/lib/pretty"
+)
+
+func main() {
+	pretty.PrintTable([][]string{
+		{"City name", "Area", "Population", "Annual Rainfall"},
+		{"Adelaide", "1295", "1158259", "600.5"},
+		{"Brisbane", "5905", "1857594", "1146.4"},
+		{"Darwin", "112", "120900", "1714.7"},
+		{"Hobart", "1357", "205556", "619.5"},
+		{"Melbourne", "1566", "3806092", "646.9"},
+		{"Perth", "5386", "1554769", "869.4"},
+		{"Sydney", "2058", "4336374", "1214.8"},
+	})
+}

lib/pretty/pretty.go

@@ -0,0 +1,64 @@
+package pretty
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strings"
+
+	"github.com/mohanson/daze/lib/doa"
+)
+
+// PrintProgress draw a progress bar in the terminal. The percent takes values ​​from 0 to 1.
+func PrintProgress(percent float64) {
+	doa.Doa(0 <= percent && percent <= 1)
+	out, _ := os.Stdout.Stat()
+	// Identify if we are displaying to a terminal or through a pipe or redirect.
+	if out.Mode()&os.ModeCharDevice == os.ModeCharDevice {
+		// Save or restore cursor position.
+		if percent == 0 {
+			log.Writer().Write([]byte{0x1b, 0x37})
+		}
+		if percent != 0 {
+			log.Writer().Write([]byte{0x1b, 0x38})
+		}
+	}
+	cap := int(percent * 44)
+	buf := []byte("[                                             ] 000%")
+	for i := 1; i < cap+1; i++ {
+		buf[i] = '='
+	}
+	buf[1+cap] = '>'
+	num := fmt.Sprintf("%3d", int(percent*100))
+	buf[48] = num[0]
+	buf[49] = num[1]
+	buf[50] = num[2]
+	log.Println("pretty:", string(buf))
+}
+
+// PrintTable easily draw tables in terminal/console applications from a list of lists of strings.
+func PrintTable(data [][]string) {
+	size := make([]int, len(data[0]))
+	for _, r := range data {
+		for j, c := range r {
+			size[j] = max(size[j], len(c))
+		}
+	}
+	line := make([]string, len(data[0]))
+	for j, c := range data[0] {
+		l := size[j]
+		line[j] = strings.Repeat(" ", l-len(c)) + c
+	}
+	log.Println("pretty:", strings.Join(line, " "))
+	for i, c := range size {
+		line[i] = strings.Repeat("-", c)
+	}
+	log.Println("pretty:", strings.Join(line, "-"))
+	for _, r := range data[1:] {
+		for j, c := range r {
+			l := size[j]
+			line[j] = strings.Repeat(" ", l-len(c)) + c
+		}
+		log.Println("pretty:", strings.Join(line, " "))
+	}
+}