implement request factory (#176)

* implement request factory

* add unit tests

Author: wenxi-zeng

core/src/main/java/com/segment/analytics/kotlin/core/Configuration.kt

@@ -36,7 +36,8 @@ data class Configuration(
     val defaultSettings: Settings = Settings(),
     var autoAddSegmentDestination: Boolean = true,
     var apiHost: String = DEFAULT_API_HOST,
-    var cdnHost: String = DEFAULT_CDN_HOST
+    var cdnHost: String = DEFAULT_CDN_HOST,
+    var requestFactory: RequestFactory = RequestFactory()
 ) {
     fun isValid(): Boolean {
         return writeKey.isNotBlank() && application != null

core/src/main/java/com/segment/analytics/kotlin/core/HTTPClient.kt

@@ -10,25 +10,18 @@ import java.net.HttpURLConnection
 import java.net.MalformedURLException
 import java.net.URL
 import java.util.zip.GZIPOutputStream
-class HTTPClient(private val writeKey: String) {
+class HTTPClient(
+    private val writeKey: String,
+    private val requestFactory: RequestFactory = RequestFactory()
+) {
 
     fun settings(cdnHost: String): Connection {
-        val connection: HttpURLConnection =
-            openConnection("https://$cdnHost/projects/$writeKey/settings")
-        connection.setRequestProperty("Content-Type", "application/json; charset=utf-8")
-        val responseCode = connection.responseCode
-        if (responseCode != HttpURLConnection.HTTP_OK) {
-            connection.disconnect()
-            throw IOException("HTTP " + responseCode + ": " + connection.responseMessage)
-        }
+        val connection: HttpURLConnection = requestFactory.settings(cdnHost, writeKey)
         return connection.createGetConnection()
     }
 
     fun upload(apiHost: String): Connection {
-        val connection: HttpURLConnection = openConnection("https://$apiHost/b")
-        connection.setRequestProperty("Content-Type", "text/plain")
-        connection.doOutput = true
-        connection.setChunkedStreamingMode(0)
+        val connection: HttpURLConnection = requestFactory.upload(apiHost)
         return connection.createPostConnection()
     }
 
@@ -129,4 +122,46 @@ internal class HTTPException(
     fun is4xx(): Boolean {
         return responseCode in 400..499
     }
+}
+
+open class RequestFactory {
+    open fun settings(cdnHost: String, writeKey: String): HttpURLConnection {
+        val connection: HttpURLConnection = openConnection("https://$cdnHost/projects/$writeKey/settings")
+        connection.setRequestProperty("Content-Type", "application/json; charset=utf-8")
+        val responseCode = connection.responseCode
+        if (responseCode != HttpURLConnection.HTTP_OK) {
+            connection.disconnect()
+            throw IOException("HTTP " + responseCode + ": " + connection.responseMessage)
+        }
+        return connection
+    }
+
+    open fun upload(apiHost: String): HttpURLConnection {
+        val connection: HttpURLConnection = openConnection("https://$apiHost/b")
+        connection.setRequestProperty("Content-Type", "text/plain")
+        connection.doOutput = true
+        connection.setChunkedStreamingMode(0)
+        return connection
+    }
+
+    /**
+     * Configures defaults for connections opened with [.upload], and [ ][.projectSettings].
+     */
+    open fun openConnection(url: String): HttpURLConnection {
+        val requestedURL: URL = try {
+            URL(url)
+        } catch (e: MalformedURLException) {
+            throw IOException("Attempted to use malformed url: $url", e)
+        }
+        val connection = requestedURL.openConnection() as HttpURLConnection
+        connection.connectTimeout = 15_000 // 15s
+        connection.readTimeout = 20_1000 // 20s
+
+        connection.setRequestProperty(
+            "User-Agent",
+            "analytics-kotlin/$LIBRARY_VERSION"
+        )
+        connection.doInput = true
+        return connection
+    }
 }

core/src/main/java/com/segment/analytics/kotlin/core/Settings.kt

@@ -106,7 +106,7 @@ internal fun Analytics.fetchSettings(
     writeKey: String,
     cdnHost: String
 ): Settings? = try {
-    val connection = HTTPClient(writeKey).settings(cdnHost)
+    val connection = HTTPClient(writeKey, this.configuration.requestFactory).settings(cdnHost)
     val settingsString =
         connection.inputStream?.bufferedReader()?.use(BufferedReader::readText) ?: ""
     log("Fetched Settings: $settingsString")

core/src/main/java/com/segment/analytics/kotlin/core/compat/ConfigurationBuilder.kt

@@ -1,6 +1,7 @@
 package com.segment.analytics.kotlin.core.compat
 
 import com.segment.analytics.kotlin.core.Configuration
+import com.segment.analytics.kotlin.core.RequestFactory
 
 /**
  * This class serves as a helper class for Java compatibility, which makes the
@@ -32,5 +33,7 @@ class ConfigurationBuilder (writeKey: String) {
 
     fun setCdnHost(cdnHost: String) = apply { configuration.cdnHost = cdnHost}
 
+    fun setRequestFactory(requestFactory: RequestFactory) = apply { configuration.requestFactory = requestFactory }
+
     fun build() = configuration
 }

core/src/main/java/com/segment/analytics/kotlin/core/platform/EventPipeline.kt

@@ -31,7 +31,7 @@ internal class EventPipeline(
 
     private var uploadChannel: Channel<String>
 
-    private val httpClient: HTTPClient = HTTPClient(apiKey)
+    private val httpClient: HTTPClient = HTTPClient(apiKey, analytics.configuration.requestFactory)
 
     private val storage get() = analytics.storage
 

core/src/test/kotlin/com/segment/analytics/kotlin/core/HTTPClientTests.kt

@@ -3,16 +3,21 @@ package com.segment.analytics.kotlin.core
 import com.segment.analytics.kotlin.core.Constants.LIBRARY_VERSION
 import io.mockk.clearConstructorMockk
 import io.mockk.every
+import io.mockk.mockk
 import io.mockk.spyk
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Assertions.assertTrue
 import org.junit.jupiter.api.Assertions.fail
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.TestInstance
+import java.io.ByteArrayOutputStream
 import java.io.IOException
 import java.io.InputStream
+import java.io.OutputStream
 import java.net.HttpURLConnection
+import java.net.MalformedURLException
 import java.net.URL
+import java.net.http.HttpClient
 
 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
 class HTTPClientTests {
@@ -80,4 +85,53 @@ class HTTPClientTests {
         }
     }
 
+    @Test
+    fun `custom requestFactory takes effect`() {
+        val httpClient = HTTPClient("123", object : RequestFactory() {
+            override fun settings(cdnHost: String, writeKey: String): HttpURLConnection {
+                return openConnection("https://cdn.test.com")
+            }
+
+            override fun upload(apiHost: String): HttpURLConnection {
+                return openConnection("https://api.test.com").apply { doOutput = true }
+            }
+
+            override fun openConnection(url: String): HttpURLConnection {
+                val requestedURL: URL = try {
+                    URL(url)
+                } catch (e: MalformedURLException) {
+                    throw IOException("Attempted to use malformed url: $url", e)
+                }
+
+                return object : HttpURLConnection(requestedURL) {
+                    override fun connect() {
+
+                    }
+
+                    override fun disconnect() {
+                    }
+
+                    override fun usingProxy() = false
+
+                    override fun getOutputStream(): OutputStream {
+                        return ByteArrayOutputStream()
+                    }
+                }
+            }
+        })
+
+        httpClient.settings("cdn-settings.segment.com/v1").connection.let {
+            assertEquals(
+                "https://cdn.test.com",
+                it.url.toString()
+            )
+        }
+
+        httpClient.upload("api.segment.io/v1").connection.let {
+            assertEquals(
+                "https://api.test.com",
+                it.url.toString()
+            )
+        }
+    }
 }

core/src/test/kotlin/com/segment/analytics/kotlin/core/compat/ConfigurationBuilderTest.kt

@@ -123,6 +123,7 @@ internal class ConfigurationBuilderTest {
             .setAutoAddSegmentDestination(expected.autoAddSegmentDestination)
             .setApiHost(expected.apiHost)
             .setCdnHost(expected.cdnHost)
+            .setRequestFactory(expected.requestFactory)
             .build()
 
         assertEquals(expected, config)

samples/java-android-app/build.gradle

@@ -3,13 +3,12 @@ plugins {
 }
 
 android {
-    compileSdkVersion 31
-    buildToolsVersion "31.0.0"
+    compileSdkVersion 33
 
     defaultConfig {
         applicationId "com.segment.analytics.javaandroidapp"
         minSdkVersion 16
-        targetSdkVersion 31
+        targetSdkVersion 33
         versionCode 1
         versionName "1.0"
 

samples/kotlin-android-app-destinations/build.gradle

@@ -5,14 +5,13 @@ plugins {
 }
 
 android {
-    compileSdkVersion 31
-    buildToolsVersion "31.0.0"
+    compileSdkVersion 33
 
     defaultConfig {
         multiDexEnabled true
         applicationId "com.segment.analytics.kotlin.destinations"
         minSdkVersion 21
-        targetSdkVersion 31
+        targetSdkVersion 33
         versionCode 3
         versionName "2.0"
 

samples/kotlin-android-app/build.gradle

@@ -6,14 +6,13 @@ plugins {
 }
 
 android {
-    compileSdkVersion 31
-    buildToolsVersion "31.0.0"
+    compileSdkVersion 33
 
     defaultConfig {
         multiDexEnabled true
         applicationId "com.segment.analytics.next"
         minSdkVersion 19
-        targetSdkVersion 31
+        targetSdkVersion 33
         versionCode 3
         versionName "2.0"