Add IPv6 support

src/ipinfo.rs

@@ -103,7 +103,7 @@ impl Default for BatchReqOpts {
 }
 
 impl IpInfo {
-    /// Construct a new IpInfo structure.
+    /// Construct a new IpInfo structure with the default URL "https://ipinfo.io".
     ///
     /// # Examples
     ///
@@ -113,13 +113,28 @@ impl IpInfo {
     /// let ipinfo = IpInfo::new(Default::default()).expect("should construct");
     /// ```
     pub fn new(config: IpInfoConfig) -> Result<Self, IpError> {
+        Self::base_request(config, "https://ipinfo.io")
+    }
+
+    /// Construct a new IpInfo structure with the URL "https://v6.ipinfo.io/".
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use ipinfo::IpInfo;
+    ///
+    /// let ipinfo = IpInfo::new(Default::default()).expect("should construct");
+    /// ```
+    pub fn new_v6(config: IpInfoConfig) -> Result<Self, IpError> {
+        Self::base_request(config, "https://v6.ipinfo.io/")
+    }
+
+    fn base_request(config: IpInfoConfig, url: &str) -> Result<Self, IpError> {
         let client =
             reqwest::Client::builder().timeout(config.timeout).build()?;
 
-        let url = "https://ipinfo.io".to_owned();
-
         let mut ipinfo_obj = Self {
-            url,
+            url: url.to_owned(),
             client,
             token: config.token,
             cache: LruCache::new(