From bc12f17e1e57bbc2e4f72cf41014c54fec8cfddf Mon Sep 17 00:00:00 2001
From: Mcat12 <newtoncat12@yahoo.com>
Date: Mon, 5 Nov 2018 11:54:52 -0500
Subject: [PATCH] Add isValidIpv4

Signed-off-by: Mcat12 <newtoncat12@yahoo.com>
---
 src/validate.js      | 23 +++++++++++++++++++++++
 src/validate.test.js | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+)

diff --git a/src/validate.js b/src/validate.js
index 096ccb1..6124190 100644
--- a/src/validate.js
+++ b/src/validate.js
@@ -50,3 +50,26 @@ export function isValidRegex(regex) {
   }
   return true;
 }
+
+/**
+ * Check if the string is a valid IPv4 address
+ *
+ * @param address {string} the address to check
+ * @returns {boolean} if the address is a valid IPv4 address
+ */
+export function isValidIpv4(address) {
+  const segments = address.split(".");
+
+  // Must have 4 segments
+  if (segments.length !== 4) {
+    return false;
+  }
+
+  // No segment can be longer than 3 characters or be empty
+  if (segments.some(segment => segment.length > 3 || segment.length === 0)) {
+    return false;
+  }
+
+  // All segments must be numbers (positive)
+  return segments.every(segment => isStrictPositiveNumber(segment));
+}
diff --git a/src/validate.test.js b/src/validate.test.js
index b16d1d3..12ca7e5 100644
--- a/src/validate.test.js
+++ b/src/validate.test.js
@@ -11,6 +11,7 @@
 import {
   isStrictPositiveNumber,
   isValidDomain,
+  isValidIpv4,
   isValidRegex
 } from "./validate";
 
@@ -149,4 +150,38 @@ describe("Testing the validation functions", () => {
       expect(isValidRegex("[0-")).toBe(false);
     });
   });
+
+  describe("isValidIpv4", () => {
+    it("passes 127.0.0.1", () => {
+      expect(isValidIpv4("127.0.0.1")).toBe(true);
+    });
+
+    it("passes 1.1.1.1", () => {
+      expect(isValidIpv4("1.1.1.1")).toBe(true);
+    });
+
+    it("passes 111.111.111.111", () => {
+      expect(isValidIpv4("111.111.111.111")).toBe(true);
+    });
+
+    it("fails 1111.1.1.1", () => {
+      expect(isValidIpv4("1111.1.1.1")).toBe(false);
+    });
+
+    it("fails 1.1.1.", () => {
+      expect(isValidIpv4("1.1.1.")).toBe(false);
+    });
+
+    it("fails empty string", () => {
+      expect(isValidIpv4("")).toBe(false);
+    });
+
+    it("fails 8.8", () => {
+      expect(isValidIpv4("8.8")).toBe(false);
+    });
+
+    it("fails 10. 10.1.1", () => {
+      expect(isValidIpv4("10. 10.1.1")).toBe(false);
+    });
+  });
 });