Initial commit

dorset-binformation.go

@@ -0,0 +1,134 @@
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+
+	"golang.org/x/net/html"
+)
+
+func getHTML(url string) (*html.Node, error) {
+	resp, err := http.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	b, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	doc, err := html.Parse(strings.NewReader(string(b)))
+	if err != nil {
+		return nil, err
+	}
+
+	return doc, nil
+}
+
+func dateToEpoch(date string) int64 {
+	layout := "Monday    2 January 2006"
+	t, err := time.Parse(layout, date)
+	if err != nil {
+		fmt.Println(err)
+	}
+	return t.Unix()
+}
+func findDates(n *html.Node, dates map[string]int64) error {
+
+	if n.Type == html.TextNode {
+		// Search for "Your next" in the text nodes
+		if strings.Contains(n.Data, "No results could be retrieved for this enquiry") {
+			return errors.New(n.Data)
+		}
+		if strings.Contains(n.Data, "Your next recycling collection day is") {
+			dates["recycling"] = dateToEpoch(n.NextSibling.FirstChild.Data)
+		}
+		if strings.Contains(n.Data, "Your next rubbish collection is") {
+			dates["rubbish"] = dateToEpoch(n.NextSibling.FirstChild.Data)
+		}
+		if strings.Contains(n.Data, "Your next food waste collection day is") {
+			dates["food"] = dateToEpoch(n.NextSibling.FirstChild.Data)
+		}
+		if strings.Contains(n.Data, "Your next garden waste collection is") {
+			dates["garden"] = dateToEpoch(n.NextSibling.FirstChild.Data)
+		}
+	}
+
+	for c := n.FirstChild; c != nil; c = c.NextSibling {
+		err := findDates(c, dates)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+func handleRequest(w http.ResponseWriter, r *http.Request, logger *log.Logger) {
+	// Splitting the path by '/'
+	pathParts := strings.Split(r.URL.Path, "/")
+
+	// Extracting the variable from the path
+	uprn := pathParts[len(pathParts)-1]
+
+	// Responding with the clients IP and extracted variable
+	logger.Printf("%s: %s", r.RemoteAddr, uprn)
+
+	// use an http get to retrieve Dorset Council html
+	doc, err := getHTML("https://gi.dorsetcouncil.gov.uk/mapping/mylocal/viewresults/" + uprn)
+
+	dates := make(map[string]int64)
+
+	// if there is an error, log it and return a 500
+	if err != nil {
+		logger.Println("Error retrieving data: ", err)
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	// If we got an error from the council (in text) pass it on
+	err = findDates(doc, dates)
+	if err != nil {
+		logger.Println("Error retrieving data: ", err)
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	// Convert the map into a JSON string
+	jsonData, err := json.Marshal(dates)
+	if err != nil {
+		logger.Println(err)
+	}
+
+	// return jsonData to the client
+	w.Header().Set("Content-Type", "application/json")
+	w.Write(jsonData)
+}
+
+func main() {
+	logger := log.New(os.Stderr, "", 0)
+
+	listenPort := ""
+
+	flag.StringVar(&listenPort, "port", ":8998", "Port to listen on")
+	flag.Parse()
+
+	// Registering the handler for requests to "/"
+	http.HandleFunc("/uprn/", func(w http.ResponseWriter, r *http.Request) {
+		handleRequest(w, r, logger)
+	})
+
+	// Starting the HTTP server on port 8998
+	logger.Println("Listening on " + listenPort)
+	err := http.ListenAndServe(listenPort, nil)
+	if err != nil {
+		logger.Println("Error starting server: ", err)
+	}
+}