From: David ‘Bombe’ Roden <bombe@pterodactylus.net>
Date: Wed, 7 Aug 2019 05:37:10 +0000 (+0200)
Subject: ♻️ Add first stab at async freenet interface
X-Git-Tag: v81^2~134
X-Git-Url: https://git.pterodactylus.net/?a=commitdiff_plain;h=85f599866faef4142c1700702af4aa57ee9daaf8;p=Sone.git

♻️ Add first stab at async freenet interface
---

diff --git a/build.gradle b/build.gradle
index a0861a6..9505ab6 100644
--- a/build.gradle
+++ b/build.gradle
@@ -44,6 +44,8 @@ dependencies {
     provided group: 'org.bouncycastle', name: 'bcprov-jdk15on', version: '1.54'
 
     compile group: 'org.jetbrains.kotlin', name: 'kotlin-stdlib-jdk8'
+    compile group: 'org.jetbrains.kotlinx', name: 'kotlinx-coroutines-core', version: '1.3.0-RC'
+
     compile group: 'net.pterodactylus', name: 'utils', version: '0.12.4'
     compile group: 'com.google.inject', name: 'guice', version: '4.2.2'
     compile group: 'com.google.guava', name: 'guava', version: '27.0.1-android'
diff --git a/src/main/kotlin/net/pterodactylus/sone/freenet/AsyncFreenetInterface.kt b/src/main/kotlin/net/pterodactylus/sone/freenet/AsyncFreenetInterface.kt
new file mode 100644
index 0000000..8219d7e
--- /dev/null
+++ b/src/main/kotlin/net/pterodactylus/sone/freenet/AsyncFreenetInterface.kt
@@ -0,0 +1,27 @@
+package net.pterodactylus.sone.freenet
+
+import freenet.client.*
+import freenet.keys.*
+import kotlinx.coroutines.*
+import net.pterodactylus.sone.core.*
+
+class AsyncFreenetInterface(private val freenetClient: FreenetClient) {
+
+	suspend fun fetchUri(freenetUri: FreenetURI): Fetched {
+		var currentUri = freenetUri
+		var result: FetchResult? = null
+		while (result == null) {
+			try {
+				result = withContext(Dispatchers.Default) { freenetClient.fetch(currentUri) }
+			} catch (fetchException: FetchException) {
+				if (fetchException.mode == FetchException.FetchExceptionMode.PERMANENT_REDIRECT) {
+					currentUri = fetchException.newURI
+					continue
+				} else
+					throw fetchException
+			}
+		}
+		return Fetched(currentUri, result)
+	}
+
+}
diff --git a/src/test/kotlin/net/pterodactylus/sone/freenet/AsyncFreenetInterfaceTest.kt b/src/test/kotlin/net/pterodactylus/sone/freenet/AsyncFreenetInterfaceTest.kt
new file mode 100644
index 0000000..915a4b5
--- /dev/null
+++ b/src/test/kotlin/net/pterodactylus/sone/freenet/AsyncFreenetInterfaceTest.kt
@@ -0,0 +1,80 @@
+/**
+ * Sone - AsyncFreenetInterfaceTest.kt - Copyright © 2019 David ‘Bombe’ Roden
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.pterodactylus.sone.freenet
+
+import freenet.client.*
+import freenet.keys.*
+import freenet.support.io.*
+import kotlinx.coroutines.*
+import net.pterodactylus.sone.core.*
+import org.hamcrest.MatcherAssert.*
+import org.hamcrest.Matchers.*
+import java.util.concurrent.atomic.*
+import kotlin.test.*
+
+class AsyncFreenetInterfaceTest {
+
+	@Test
+	fun `returned deferred is completed by success`() = runBlocking {
+		val result = FetchResult(ClientMetadata(), NullBucket())
+		val freenetClient = object : FreenetClient {
+			override fun fetch(freenetKey: FreenetURI) = result
+		}
+		val freenetInterface = AsyncFreenetInterface(freenetClient)
+		val fetched = async { freenetInterface.fetchUri(FreenetURI("KSK@GPL.txt")) }
+
+		withTimeout(1000) {
+			assertThat(fetched.await(), equalTo(Fetched(FreenetURI("KSK@GPL.txt"), result)))
+		}
+	}
+
+	@Test
+	fun `permanent redircts are being followed`() = runBlocking {
+		val result = FetchResult(ClientMetadata(), NullBucket())
+		val freenetClient = object : FreenetClient {
+			val redirected = AtomicBoolean(false)
+			override fun fetch(freenetKey: FreenetURI) =
+					if (redirected.compareAndSet(false, true))
+						throw FetchException(FetchException.FetchExceptionMode.PERMANENT_REDIRECT, FreenetURI("KSK@GPLv3.txt"))
+					else result
+		}
+		val freenetInterface = AsyncFreenetInterface(freenetClient)
+		val fetched = async { freenetInterface.fetchUri(FreenetURI("KSK@GPL.txt")) }
+
+		withTimeout(1000) {
+			assertThat(fetched.await(), equalTo(Fetched(FreenetURI("KSK@GPLv3.txt"), result)))
+		}
+	}
+
+	@Test
+	fun `fetch errors are being re-thrown`() = runBlocking<Unit> {
+		val freenetClient = object : FreenetClient {
+			override fun fetch(freenetKey: FreenetURI) =
+					throw FetchException(FetchException.FetchExceptionMode.ALL_DATA_NOT_FOUND)
+		}
+		val freenetInterface = AsyncFreenetInterface(freenetClient)
+		val fetched = supervisorScope { async { freenetInterface.fetchUri(FreenetURI("KSK@GPL.txt")) } }
+
+		withTimeout(1000) {
+			assertFailsWith(FetchException::class) {
+				fetched.await()
+			}
+		}
+	}
+
+}