fix: randomize fallback hosts (#319)

Author: aallam

client/src/commonMain/kotlin/com/algolia/search/transport/internal/Host.kt

@@ -10,20 +10,22 @@ internal val ApplicationID.searchHosts
     get() = listOf(
         RetryableHost("$this-dsn.algolia.net", CallType.Read),
         RetryableHost("$this.algolia.net", CallType.Write),
+    ) + mutableListOf(
         RetryableHost("$this-1.algolianet.com"),
         RetryableHost("$this-2.algolianet.com"),
         RetryableHost("$this-3.algolianet.com")
-    )
+    ).apply { shuffle() }
 
 internal val insightHosts = listOf(RetryableHost("insights.algolia.io"))
 internal val Region.Analytics.hosts get() = listOf(RetryableHost("analytics.$this.algolia.com"))
 internal val Region.Personalization.hosts get() = listOf(RetryableHost("personalization.$this.algolia.com"))
 internal val placesHosts = listOf(
     RetryableHost("places-dsn.algolia.net"),
+) + mutableListOf(
     RetryableHost("places-1.algolianet.com"),
     RetryableHost("places-2.algolianet.com"),
     RetryableHost("places-3.algolianet.com")
-)
+).apply { shuffle() }
 
 @PublishedApi
 internal fun RetryableHost.reset() {

client/src/commonTest/kotlin/Helper.kt

@@ -38,6 +38,10 @@ internal infix fun <T> Collection<T>?.shouldNotContain(element: T) {
     (this?.contains(element) ?: false).shouldBeFalse()
 }
 
+internal infix fun <T> Collection<T>?.shouldContainAll(collection: Collection<T>) {
+    (this?.containsAll(collection) ?: false).shouldBeTrue()
+}
+
 internal fun <T> Collection<T>.shouldBeEmpty() {
     this.isEmpty().shouldBeTrue()
 }
@@ -77,3 +81,4 @@ internal inline fun <reified T : Throwable> shouldFailWith(noinline block: suspe
         }
     }
 }
+

client/src/commonTest/kotlin/configuration/TestConfiguration.kt

@@ -20,6 +20,7 @@ import io.ktor.client.features.logging.LogLevel
 import shouldBeNull
 import shouldEqual
 import kotlin.test.Test
+import shouldContainAll
 
 internal class TestConfiguration {
 
@@ -39,7 +40,7 @@ internal class TestConfiguration {
             writeTimeout shouldEqual DEFAULT_WRITE_TIMEOUT
             readTimeout shouldEqual DEFAULT_READ_TIMEOUT
             logLevel shouldEqual LogLevel.NONE
-            hosts shouldEqual applicationID.searchHosts
+            hosts shouldContainAll applicationID.searchHosts
             defaultHeaders.shouldBeNull()
             engine.shouldBeNull()
             httpClientConfig.shouldBeNull()

client/src/commonTest/kotlin/transport/TestCallableHosts.kt

@@ -8,6 +8,7 @@ import com.algolia.search.transport.internal.Transport
 import runBlocking
 import shouldEqual
 import kotlin.test.Test
+import shouldContainAll
 
 internal class TestCallableHosts {
 
@@ -24,7 +25,7 @@ internal class TestCallableHosts {
         runBlocking {
             val hosts = transport.callableHosts(CallType.Read)
 
-            hosts shouldEqual listOf(
+            hosts shouldContainAll listOf(
                 hostRead,
                 hostFallback1,
                 hostFallback2,
@@ -38,7 +39,7 @@ internal class TestCallableHosts {
         runBlocking {
             val hosts = transport.callableHosts(CallType.Write)
 
-            hosts shouldEqual listOf(
+            hosts shouldContainAll listOf(
                 hostWrite,
                 hostFallback1,
                 hostFallback2,
@@ -67,7 +68,7 @@ internal class TestCallableHosts {
 
             val hosts = transport.callableHosts(CallType.Read)
 
-            hosts shouldEqual listOf(hostfallback3)
+            hosts shouldEqual listOf(transport.hosts.last())
         }
     }
 
@@ -78,7 +79,7 @@ internal class TestCallableHosts {
 
             val hosts = transport.callableHosts(CallType.Write)
 
-            hosts shouldEqual listOf(
+            hosts shouldContainAll  listOf(
                 hostWrite,
                 hostFallback1,
                 hostFallback2,

client/src/commonTest/kotlin/transport/TestRetryableHost.kt

@@ -9,6 +9,7 @@ import com.algolia.search.transport.internal.reset
 import com.algolia.search.transport.internal.searchHosts
 import shouldEqual
 import kotlin.test.Test
+import shouldContainAll
 
 internal class TestRetryableHost {
 
@@ -17,7 +18,7 @@ internal class TestRetryableHost {
 
     @Test
     fun searchHosts() {
-        applicationID.searchHosts shouldEqual listOf(
+        applicationID.searchHosts shouldContainAll listOf(
             RetryableHost("$applicationID-dsn.algolia.net", CallType.Read),
             RetryableHost("$applicationID.algolia.net", CallType.Write),
             RetryableHost("$applicationID-1.algolianet.com"),