Data commit

Task/Web-scraping/Go/web-scraping.go

@@ -0,0 +1,56 @@
+package main
+
+import (
+    "bytes"
+    "encoding/xml"
+    "fmt"
+    "io"
+    "net/http"
+    "regexp"
+    "time"
+)
+
+func main() {
+    resp, err := http.Get("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
+    if err != nil {
+        fmt.Println(err) // connection or request fail
+        return
+    }
+    defer resp.Body.Close()
+    var us string
+    var ux int
+    utc := []byte("UTC")
+    for p := xml.NewDecoder(resp.Body); ; {
+        t, err := p.RawToken()
+        switch err {
+        case nil:
+        case io.EOF:
+            fmt.Println("UTC not found")
+            return
+        default:
+            fmt.Println(err) // read or parse fail
+            return
+        }
+        if ub, ok := t.(xml.CharData); ok {
+            if ux = bytes.Index(ub, utc); ux != -1 {
+                // success: found a line with the string "UTC"
+                us = string([]byte(ub))
+                break
+            }
+        }
+    }
+    // first thing to try: parsing the expected date format
+    if t, err := time.Parse("Jan. 2, 15:04:05 UTC", us[:ux+3]); err == nil {
+        fmt.Println("parsed UTC:", t.Format("January 2, 15:04:05"))
+        return
+    }
+    // fallback: search for anything looking like a time and print that
+    tx := regexp.MustCompile("[0-2]?[0-9]:[0-5][0-9]:[0-6][0-9]")
+    if justTime := tx.FindString(us); justTime > "" {
+        fmt.Println("found UTC:", justTime)
+        return
+    }
+    // last resort: just print the whole element containing "UTC" and hope
+    // there is a human readable time in there somewhere.
+    fmt.Println(us)
+}