Implemented IsgdException. Closes #1

.github/workflows/gradle.yml

@@ -5,22 +5,28 @@ on: [push, pull_request, workflow_dispatch]
 jobs:
   build:
     runs-on: ubuntu-latest
+
     env:
       GRADLE_OPTS: "-Dorg.gradle.jvmargs=-XX:MaxMetaspaceSize=512m"
       SONAR_JDK: "11"
+
     strategy:
       matrix:
         java-version: [ 1.8, 11, 15 ]
+
     steps:
       - uses: actions/checkout@v2
         with:
           fetch-depth: 0
+
       - name: Set up JDK ${{ matrix.java-version }}
         uses: actions/setup-java@v1
         with:
           java-version: ${{ matrix.java-version }}
+
       - name: Grant execute permission for gradlew
         run: chmod +x gradlew
+
       - name: Cache SonarCloud packages
         if: matrix.java-version == env.SONAR_JDK
         uses: actions/cache@v1
@@ -28,6 +34,7 @@ jobs:
           path: ~/.sonar/cache
           key: ${{ runner.os }}-sonar
           restore-keys: ${{ runner.os }}-sonar
+
       - name: Cache Gradle packages
         uses: actions/cache@v2
         with:
@@ -37,14 +44,17 @@ jobs:
           key: ${{ runner.os }}-gradle-${{ matrix.java-version }}-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
           restore-keys: |
             ${{ runner.os }}-gradle-${{ matrix.java-version }}-
+
       - name: Test with Gradle
         run: ./gradlew build check --stacktrace
+
       - name: SonarCloud
         if: success() && matrix.java-version == env.SONAR_JDK
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
         run: ./gradlew sonarqube
+
       - name: Cleanup Gradle Cache
         run: |
           rm -f ~/.gradle/caches/modules-2/modules-2.lock

README.md

@@ -58,6 +58,24 @@ dependencies {
 ```
 Instructions for using with Maven, Ivy, etc. can be found on [Maven Central](https://search.maven.org/artifact/net.thauvin.erik/isgd-shorten/0.9.2/jar).
 
+### Errors
+
+An `IsgdException` is thrown when an API error occurs. The error message (text, XML or JSON) and HTTP status code can be retrieved as follows: 
+
+```kotlin
+try {
+    Isgd.shorten("http://is.gd/Pt2sET") // already shorten
+} catch (e: IsgdException)
+    println("Status Code: ${e.statusCode}")
+    println("${e.message})
+}
+```
+
+```
+Status Code: 400
+Error: Sorry, the URL you entered is on our internal blacklist. It may have been used abusively in the past, or it may link to another URL redirection service.
+```
+
 ### v.gd
 
 Additionally, link can be shortened using [v.gd](https://v.gd/) by setting the `isVgd` flag:

config/detekt/baseline.xml

@@ -3,5 +3,7 @@
   <ManuallySuppressedIssues/>
   <CurrentIssues>
     <ID>LongParameterList:Isgd.kt$Isgd.Companion$( url: String, shorturl: String = "", callback: String = "", logstats: Boolean = false, format: Format = Format.SIMPLE, isVgd: Boolean = false )</ID>
+    <ID>MagicNumber:Isgd.kt$Isgd.Companion$200</ID>
+    <ID>MagicNumber:Isgd.kt$Isgd.Companion$399</ID>
   </CurrentIssues>
 </SmellBaseline>

examples/src/main/java/com/example/IsgdSample.java

@@ -1,16 +1,21 @@
 package com.example;
 
 import net.thauvin.erik.isgd.Isgd;
+import net.thauvin.erik.isgd.IsgdException;
 
 public final class IsgdSample {
     public static void main(final String[] args) {
         if (args.length > 0) {
             for (final String arg : args) {
+                try {
                     if (arg.contains("is.gd")) {
                         System.out.println(arg + " <-- " + Isgd.lookup(arg));
                     } else {
                         System.out.println(arg + " --> " + Isgd.shorten(arg));
                     }
+                } catch (IsgdException e) {
+                    System.out.println(e.getMessage());
+                }
             }
         } else {
             System.err.println("Try specifying one or more URLs as arguments.");

examples/src/main/kotlin/com/example/IsgdExample.kt

@@ -1,15 +1,20 @@
 package com.example
 
 import net.thauvin.erik.isgd.Isgd
+import net.thauvin.erik.isgd.IsgdException
 import kotlin.system.exitProcess
 
 fun main(args: Array<String>) {
     if (args.isNotEmpty()) {
         args.forEach {
+            try {
                 if (it.contains("is.gd"))
                     println(it + " <-- " + Isgd.lookup(it))
                 else
                     println(it + " --> " + Isgd.shorten(it))
+            } catch (e: IsgdException) {
+                println(e.message)
+            }
         }
     } else {
         println("Try specifying one or more URLs as arguments.")

pom.xml

@@ -35,11 +35,22 @@
     <system>GitHub</system>
     <url>https://github.com/ethauvin/isgd-shorten/issues</url>
   </issueManagement>
+  <dependencyManagement>
+    <dependencies>
+      <dependency>
+        <groupId>org.jetbrains.kotlin</groupId>
+        <artifactId>kotlin-bom</artifactId>
+        <version>1.5.10</version>
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
+    </dependencies>
+  </dependencyManagement>
   <dependencies>
     <dependency>
       <groupId>org.jetbrains.kotlin</groupId>
       <artifactId>kotlin-stdlib-jdk8</artifactId>
-      <version>1.5.0</version>
+      <version>1.5.10</version>
       <scope>compile</scope>
     </dependency>
   </dependencies>

src/main/kotlin/net/thauvin/erik/isgd/Isgd.kt

@@ -38,7 +38,7 @@ import java.net.URLEncoder
 import java.nio.charset.StandardCharsets
 
 /**
- * See the [is.gd API](https://is.gd/apishorteningreference.php)
+ * See the [is.gd API](https://is.gd/apishorteningreference.php).
  */
 enum class Format(val type: String) {
     WEB("web"), SIMPLE("simple"), XML("xml"), JSON("json")
@@ -48,18 +48,25 @@ fun String.encode(): String {
     return URLEncoder.encode(this, StandardCharsets.UTF_8.name())
 }
 
+/**
+ * Implements the [is.gd API](https://is.gd/developers.php).
+ */
 class Isgd private constructor() {
     companion object {
         private fun callApi(url: String): String {
             val connection = URL(url).openConnection() as HttpURLConnection
             connection.setRequestProperty(
                 "User-Agent",
-                "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:75.0) Gecko/20100101 Firefox/75.0"
+                "Mozilla/5.0 (Linux x86_64; rv:89.0) Gecko/20100101 Firefox/89.0"
             )
+            if (connection.responseCode in 200..399) {
                 return connection.inputStream.bufferedReader().readText()
+            } else {
+                throw IsgdException(connection.responseCode, connection.errorStream.bufferedReader().readText())
+            }
         }
 
-        private fun host(isVgd: Boolean = false): String {
+        private fun getHost(isVgd: Boolean = false): String {
             return if (isVgd) "v.gd" else "is.gd"
         }
 
@@ -68,6 +75,7 @@ class Isgd private constructor() {
          */
         @JvmStatic
         @JvmOverloads
+        @Throws(IsgdException::class)
         fun lookup(
             shorturl: String,
             callback: String = "",
@@ -78,7 +86,7 @@ class Isgd private constructor() {
                 throw IllegalArgumentException("Please specify a valid short URL to lookup.")
             }
 
-            val sb = StringBuilder("https://${host(isVgd)}/forward.php?shorturl=${shorturl.encode()}")
+            val sb = StringBuilder("https://${getHost(isVgd)}/forward.php?shorturl=${shorturl.encode()}")
 
             if (callback.isNotEmpty()) {
                 sb.append("&callback=${callback.encode()}")
@@ -94,6 +102,7 @@ class Isgd private constructor() {
          */
         @JvmStatic
         @JvmOverloads
+        @Throws(IsgdException::class)
         fun shorten(
             url: String,
             shorturl: String = "",
@@ -106,7 +115,7 @@ class Isgd private constructor() {
                 throw IllegalArgumentException("Please enter a valid URL to shorten.")
             }
 
-            val sb = StringBuilder("https://${host(isVgd)}/create.php?url=${url.encode()}")
+            val sb = StringBuilder("https://${getHost(isVgd)}/create.php?url=${url.encode()}")
 
             if (shorturl.isNotEmpty()) {
                 sb.append("&shorturl=${shorturl.encode()}")

src/main/kotlin/net/thauvin/erik/isgd/IsgdException.kt

@@ -0,0 +1,45 @@
+/*
+ * IsgdException.kt
+ *
+ * Copyright (c) 2020-2021, Erik C. Thauvin (erik@thauvin.net)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above copyright notice, this
+ *   list of conditions and the following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above copyright notice,
+ *   this list of conditions and the following disclaimer in the documentation
+ *   and/or other materials provided with the distribution.
+ *
+ *   Neither the name of this project nor the names of its contributors may be
+ *   used to endorse or promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package net.thauvin.erik.isgd
+
+/**
+ * Thrown when an exceptional condition has occurred.
+ *
+ * @property statusCode The HTTP status code.
+ * @property message The error message.
+ */
+class IsgdException(val statusCode: Int, message: String) : Exception(message) {
+    companion object {
+        private const val serialVersionUID = 1L
+    }
+}

src/test/kotlin/net/thauvin/erik/isgd/IsgdTest.kt

@@ -34,6 +34,7 @@ package net.thauvin.erik.isgd
 
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFailsWith
 import kotlin.test.assertTrue
 
 class IsgdTest {
@@ -41,6 +42,21 @@ class IsgdTest {
     private val shortUrl = "https://is.gd/Pt2sET"
     private val shortVgdUrl = "https://v.gd/2z2ncj"
 
+    @Test
+    fun testException() {
+        assertFailsWith(
+            message = "URL is already shorten",
+            exceptionClass = IsgdException::class,
+            block = { Isgd.shorten(shortUrl) }
+        )
+
+        try {
+            Isgd.shorten(shortUrl)
+        } catch (e: IsgdException) {
+            assertTrue(e.statusCode == 400, "status code == 400")
+        }
+    }
+
     @Test
     fun testLookupDefault() {
         assertEquals(url, Isgd.lookup(shortUrl))