Version 1.2: Add error handling

API.go

@@ -1,13 +1,23 @@
 package main
 
 import (
+	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"net"
 	"net/http"
+	"os"
+	"sort"
+	"strings"
 )
 
 func getLocalIP() string {
-	resp, _ := http.Get("https://api.ipify.org")
+	resp, err := http.Get("https://api.ipify.org")
+	if err != nil {
+		fmt.Println("FATAL: Cannot get local IP.")
+		os.Exit(2)
+		return ""
+	}
 	body, _ := ioutil.ReadAll(resp.Body)
 	return string(body[:])
 }
@@ -24,3 +34,37 @@ func resolveDNSHostname(hostname string) string {
 	address, _ := net.LookupHost(hostname)
 	return address[0]
 }
+
+func getIPInfo(ipaddress string) IPAddressInfo {
+	apiEndpoint := "http://ip-api.com/json/" + ipaddress
+	resp, err := http.Get(apiEndpoint)
+	if err != nil {
+		fmt.Println("FATAL: Cannot contact IP address information API.")
+		os.Exit(3)
+	}
+	body, _ := ioutil.ReadAll(resp.Body)
+	infoString := string(body)
+	var info IPAddressInfo
+	err = json.Unmarshal([]byte(infoString), &info)
+	if err != nil {
+		fmt.Println("FATAL: Cannot serialize recieved IP address data.")
+		os.Exit(4)
+	}
+	return info
+}
+
+func getBGPPrefixes(as string) {
+	apiEndpoint := "https://api.hackertarget.com/aslookup/?q=" + as
+	resp, err := http.Get(apiEndpoint)
+	if err != nil {
+		fmt.Println("FATAL: Cannot contact BGP Prefixes API.")
+		os.Exit(5)
+	}
+	body, _ := ioutil.ReadAll(resp.Body)
+	prefixesString := string(body)
+	var prefixes = strings.Split(prefixesString, "\n")[1:]
+	sort.Strings(prefixes)
+	for index := range prefixes {
+		fmt.Println(prefixes[index])
+	}
+}