v1.x.y
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The easiest HTTP networking library for Kotlin/Android.
Support basic HTTP GET/POST/PUT/DELETE/HEAD/PATCH in a fluent style interface
Support both asynchronous and blocking requests
Download file
Upload file (multipart/form-data)
Cancel in-flight request
Request timeout
Configuration manager by using
FuelManagerDebug log / cUrl log
Support response deserialization into plain old object (both Kotlin & Java)
Automatically invoke handler on Android Main Thread when using Android Module
Special test mode for easier testing
Support for reactive programming via RxJava 2.x and Project Reactor 3.x
Google Components LiveData support
Built-in object serialization module (kotlinx-serialization, Gson, Jackson, Moshi, Forge) :sparkles:
Support Kotlin's Coroutines module
API Routing
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​​Kotlin - 1.2.71
Coroutine - 0.23.3
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​​Kotlin - 1.3.0-rc-146
Coroutine - 0.30.1-eap13
​Result - The modelling for success/failure of operations in Kotlin
​Android SDK - Android SDK
Min SDK: 19
​Live Data - Android Architecture Components - LiveData
​RxJava - RxJava – Reactive Extensions for the JVM
​Coroutines - Kotlin Coroutines - Library support for Kotlin coroutines
​Kotlinx Serialization - Kotlinx Serialization - Kotlin cross-platform / multi-format serialization
​Gson - Gson - A Java serialization/deserialization library to convert Java Objects into JSON and back
​Jackson - Jackson - The JSON library for Java
​Moshi - Moshi - A modern JSON library for Android and Java
​Forge - Forge - Functional style JSON parsing written in Kotlin
​Project Reactor - Project Reactor - Implementation of Reactive Streams standard
repositories {jcenter()}​dependencies {compile 'com.github.kittinunf.fuel:fuel:<latest-version>' //for JVMcompile 'com.github.kittinunf.fuel:fuel-android:<latest-version>' //for Androidcompile 'com.github.kittinunf.fuel:fuel-livedata:<latest-version>' //for LiveData supportcompile 'com.github.kittinunf.fuel:fuel-rxjava:<latest-version>' //for RxJava supportcompile 'com.github.kittinunf.fuel:fuel-coroutines:<latest-version>' //for Kotlin Coroutines supportcompile 'com.github.kittinunf.fuel:fuel-gson:<latest-version>' //for Gson supportcompile 'com.github.kittinunf.fuel:fuel-jackson:<latest-version>' //for Jackson supportcompile 'com.github.kittinunf.fuel:fuel-moshi:<latest-version>' //for Moshi supportcompile 'com.github.kittinunf.fuel:fuel-forge:<latest-version>' //for Forge supportcompile 'com.github.kittinunf.fuel:fuel-reactor:<latest-version>' //for Reactor support}
There are two samples, one is in Kotlin and another one in Java.
Kotlin
```kotlin
//an extension over string (support GET, PUT, POST, DELETE with httpGet(), httpPut(), httpPost(), httpDelete())
"https://httpbin.org/get".httpGet().responseString { request, response, result ->
//do something with response
when (result) {
is Result.Failure -> {
val ex = result.getException()}
is Result.Success -> {
val data = result.get()}
}
}
//if we set baseURL beforehand, simply use relativePath FuelManager.instance.basePath = "https://httpbin.org" "/get".httpGet().responseString { request, response, result -> //make a GET to https://httpbin.org/get and do something with response val (data, error) = result if (error == null) { //do something when success } else { //error handling } }
//if you prefer this a little longer way, you can always do //get Fuel.get("https://httpbin.org/get").responseString { request, response, result -> //do something with response result.fold({ d -> //do something with data }, { err -> //do something with error }) }
* Java```java//getFuel.get("https://httpbin.org/get", params).responseString(new Handler<String>() {@Overridepublic void failure(Request request, Response response, FuelError error) {//do something when it is failure}​@Overridepublic void success(Request request, Response response, String data) {//do something when it is successful}});
You can also wait for the response. It returns the same parameters as the async version, but it blocks the thread. It supports all the features of the async version.
Kotlin
val (request, response, result) = "https://httpbin.org/get".httpGet().responseString() // result is Result<String, FuelError>Java
```java try { Triple data = Fuel.get("https://www.google.com").responseString(); Request request = data.getFirst(); Response response = data.getSecond(); Result text = data.getThird(); } catch (Exception networkError) {
}
## Detail Usage​### GET​```kotlinFuel.get("https://httpbin.org/get").response { request, response, result ->println(request)println(response)val (bytes, error) = resultif (bytes != null) {println(bytes)}}
​Result is a functional style data structure that represents data that contains result of Success or Failure but not both. It represents the result of an action that can be success (with result) or error.
Working with result is easy. You could fold, destructure as because it is just a data class or do a simple
whenchecking whether it is Success or Failure.
fun response(handler: (Request, Response, Result<ByteArray, FuelError>) -> Unit)
fun responseString(handler: (Request, Response, Result<String, FuelError>) -> Unit)
requires the android extension​
fun responseJson(handler: (Request, Response, Result<Json, FuelError>) -> Unit)​val jsonObject = json.obj() //JSONObjectval jsonArray = json.array() //JSONArray
fun <T> responseObject(deserializer: ResponseDeserializable<T>, handler: (Request, Response, Result<T, FuelError>) -> Unit)
Fuel.post("https://httpbin.org/post").response { request, response, result ->}​// JSON body from string (automatically sets application/json as Content-Type)Fuel.post("https://httpbin.org/post").jsonBody("{ \"foo\" : \"bar\" }").response { request, response, result -> }​// Body from a generic stringFuel.post("https://httpbin.org/post").header(Headers.CONTENT_TYPE, "text/plain").body("my body is plain").response { request, response, result -> }​// Body from a fileFuel.post("https://httpbin.org/post").header(Headers.CONTENT_TYPE, "text/plain").body(File("lipsum.txt")).response { request, response, result -> }​// Body from a generic streamval stream = ByteArrayInputStream("source-string-from-string".toByteArray())Fuel.post("https://httpbin.org/post").header(Headers.CONTENT_TYPE, "text/plain").body(stream).response { request, response, result -> }
Fuel.put("https://httpbin.org/put").response { request, response, result -> }​// Supports all the body methods, like POST requests
Fuel.delete("https://httpbin.org/delete").response { request, response, result -> }​// Supports all the body methods, like POST requests
Fuel.head("https://httpbin.org/get").response { request, response, result -> /* request body is empty */ }
The default
clientisHttpClientwhich is a thin wrapper overjava.net.HttpUrlConnection.java.net.HttpUrlConnectiondoes not support a [PATCH](https://download.java.net/jdk7/archive/b123/docs/api/java/net/HttpURLConnection.html#setRequestMethod(java.lang.String)) method.HttpClientconvertsPATCHrequests to aPOSTrequest and adds aX-HTTP-Method-Override: PATCHheader. While this is a semi-standard industry practice not all APIs are configured to accept this header by default.
Fuel.patch("https://httpbin.org/patch").response { request, response, result -> }​// Supports all the body methods, like POST requests
Connect is not supported by the Java JVM via the regular HTTP clients, and is therefore not supported.
There are no convenience methods for making an OPTIONS request, but you can still make one directly:
Fuel.request(Method.OPTIONS, "https://httpbin.org/anything").response { request, response, result -> }
There are no convenience methods for making an TRACE request, but you can still make one directly:
Fuel.request(Method.TRACE, "https://httpbin.org/anything").response { request, response, result -> }
Use
toString()method to inspect requests
val request = Fuel.get("https://httpbin.org/get", parameters = listOf("key" to "value"))println(request)​// --> GET (https://httpbin.org/get?key=value)// Body : (empty)// Headers : (2)// Accept-Encoding : compress;q=0.5, gzip;q=1.0// Device : Android
Use
toString()method to inspect responses
val (_, response, _) = Fuel.get("https://httpbin.org/get", parameters = listOf("key" to "value")).response()println(response)// <-- 200 (https://httpbin.org/get?key=value)// Body : (empty)
Also support cUrl string to Log request, make it very easy to cUrl on command line
val request = Fuel.post("https://httpbin.org/post", parameters = listOf("foo" to "foo", "bar" to "bar", "key" to "value"))println(request.cUrlString())
curl -i -X POST -d "foo=foo&bar=bar&key=value" -H "Accept-Encoding:compress;q=0.5, gzip;q=1.0" -H "Device:Android" -H "Content-Type:application/x-www-form-urlencoded" "https://httpbin.org/post"
URL encoded style for GET & DELETE request
Fuel.get("https://httpbin.org/get", listOf("foo" to "foo", "bar" to "bar")).response { request, response, result -> }// resolve to https://httpbin.org/get?foo=foo&bar=bar​Fuel.delete("https://httpbin.org/delete", listOf("foo" to "foo", "bar" to "bar")).response { request, response, result -> }// resolve to https://httpbin.org/delete?foo=foo&bar=bar
Array support for GET requests
Fuel.get("https://httpbin.org/get", listOf("foo" to "foo", "dwarf" to arrayOf("grumpy","happy","sleepy","dopey"))).response { request, response, result -> }// resolve to https://httpbin.org/get?foo=foo&dwarf[]=grumpy&dwarf[]=happy&dwarf[]=sleepy&dwarf[]=dopey
Support x-www-form-urlencoded for PUT & POST
Fuel.post("https://httpbin.org/post", listOf("foo" to "foo", "bar" to "bar")).response { request, response, result -> }// Body : "foo=foo&bar=bar"​Fuel.put("https://httpbin.org/put", listOf("foo" to "foo", "bar" to "bar")).response { request, response, result -> }// Body : "foo=foo&bar=bar"
Default timeout for a request is 15000 milliseconds. Default read timeout for a request is 15000 milliseconds.
Kotlin
```kotlin
val timeout = 5000 // 5000 milliseconds = 5 seconds.
val timeoutRead = 60000 // 60000 milliseconds = 1 minute.
Fuel.get("https://httpbin.org/get") .timeout(timeout) .timeoutRead(timeoutRead) .responseString { request, response, result -> }
* Java```javaint timeout = 5000 // 5000 milliseconds = 5 seconds.int timeoutRead = 60000 // 60000 milliseconds = 1 minute.Fuel.get("https://httpbin.org/get", params).timeout(timeout).timeoutRead(timeoutRead).responseString(new Handler<String>() {@Overridepublic void failure(Request request, Response response, FuelError error) {//do something when it is failure}​@Overridepublic void success(Request request, Response response, String data) {//do something when it is successful}});
Fuel.download("https://httpbin.org/bytes/32768").destination { response, url -> File.createTempFile("temp", ".tmp") }.response { req, res, result -> }​Fuel.download("https://httpbin.org/bytes/32768").destination { response, url -> File.createTempFile("temp", ".tmp") }.progress { readBytes, totalBytes ->val progress = readBytes.toFloat() / totalBytes.toFloat() * 100println("Bytes downloaded $readBytes / $totalBytes ($progress %)")}.response { req, res, result -> }
Fuel.upload("/post").source { request, url -> File.createTempFile("temp", ".tmp") }.responseString { request, response, result -> }​// By default upload use Method.POST, unless it is specified as something elseFuel.upload("/put", Method.PUT).source { request, url -> File.createTempFile("temp", ".tmp") }.responseString { request, response, result -> }​// Upload with multiple filesFuel.upload("/post").sources { request, url ->listOf(File.createTempFile("temp1", ".tmp"),File.createTempFile("temp2", ".tmp"))}.name { "temp" }.responseString { request, response, result -> }
Fuel.upload("/post").dataParts { request, url ->listOf(//DataPart takes a file, and you can specify the name and/or typeDataPart(File.createTempFile("temp1", ".tmp"), "image/jpeg"),DataPart(File.createTempFile("temp2", ".tmp"), "file2"),DataPart(File.createTempFile("temp3", ".tmp"), "third-file", "image/jpeg"))}.responseString { request, response, result -> /* ... */ }
val formData = listOf("Email" to "[email protected]", "Name" to "Joe Smith" )Fuel.upload("/post", param = formData)// Upload normally requires a file, but we can give it an empty list of `DataPart`.dataParts { request, url -> listOf<DataPart>() }.responseString { request, response, result -> /* ... */ }
Fuel.upload("/post").blob { request, url -> Blob("filename.png", someObject.length) { someObject.getInputStream() } }
Support Basic Authentication right off the box
val username = "username"val password = "abcd1234"​Fuel.get("https://httpbin.org/basic-auth/$user/$password").basicAuthentication(username, password).response { request, response, result -> }Support Bearer Authentication
val token = "mytoken"​Fuel.get("https://httpbin.org/bearer").bearerAuthentication(token).response { request, response, result -> }Support Any authentication by header
Fuel.get("https://httpbin.org/anything").header(Headers.AUTHORIZATION, "Custom secret").response { request, response, result -> }
By default, the valid range for HTTP status code will be (200..299).
If one wants to cancel on-going request, one could call
cancelon the request objectval request = Fuel.get("https://httpbin.org/get").response { request, response, result ->// if request is cancelled successfully, response callback will not be called.// Interrupt callback (if provided) will be called instead}​//laterrequest.cancel() //this will cancel on-going requestAlso, interrupt request can be further processed with interrupt callback
val request = Fuel.get("https://httpbin.org/get").interrupt { request -> println("${request.url} was interrupted and cancelled") }.response { request, response, result ->// if request is cancelled successfully, response callback will not be called.// Interrupt callback (if provided) will be called instead}​request.cancel()
Fuel provides built-in support for response deserialization. Here is how one might want to use Fuel together with Gson​
```kotlin //User Model data class User(val firstName: String = "", val lastName: String = "") {
//User Deserializer class Deserializer : ResponseDeserializable { override fun deserialize(content: String) = Gson().fromJson(content, User::class.java) }
}
//Use httpGet extension "https://www.example.com/user/1".httpGet().responseObject(User.Deserializer()) { req, res, result -> //result is of type Result val (user, err) = result
println(user.firstName)println(user.lastName)
}
### Gson Deserialization​* Fuel also provides a built in support for Gson Deserialization. This is possible by including the [Gson](https://github.com/kittinunf/Fuel/tree/master/fuel-gson) module in your dependency block.​```kotlindata class HttpBinUserAgentModel(var userAgent: String = "")Fuel.get("/user-agent").responseObject<HttpBinUserAgentModel> { _, _, result -> }
requires the kotlinx-serialization extension requires kotlinx.serialization​
@Serializabledata class HttpBinUserAgentModel(var userAgent: String = "")​Fuel.get("/user-agent").responseObject<HttpBinUserAgentModel> { _, _, result -> }
This is by default strict and will reject unknown keys, for that you can pass a custom JSOn instance
JSON(nonstrict = true)
@Serializabledata class HttpBinUserAgentModel(var userAgent: String = "")​Fuel.get("/user-agent").responseObject<HttpBinUserAgentModel>(json = JSON(nonstrict = true)) { _, _, result -> }
kotlinx.serialization can not always guess the correct serialzer to use, when generics are involved for example
@Serializabledata class HttpBinUserAgentModel(var userAgent: String = "")​Fuel.get("/list/user-agent").responseObject<HttpBinUserAgentModel>(loader = HttpBinUserAgentModel.serilaizer().list) { _, _, result -> }
It can be used with coroutines by using kotlinxDeserilaizerOf() it takes the same json and loader as parameters
@Serializabledata class HttpBinUserAgentModel(var userAgent: String = "")​Fuel.get("/user-agent").awaitResponseObject<HttpBinUserAgentModel>(kotlinxDeserializerOf()) { _, _, result -> }
There are 4 methods to support response deserialization depending on your needs (also depending on JSON parsing library of your choice), and you are required to implement only one of them.
fun deserialize(bytes: ByteArray): T?​fun deserialize(inputStream: InputStream): T?​fun deserialize(reader: Reader): T?​fun deserialize(content: String): T?Another example may be parsing a website that is not UTF-8. By default, Fuel serializes text as UTF-8, we need to define our deserializer as such
object Windows1255StringDeserializer : ResponseDeserializable<String> {override fun deserialize(bytes: ByteArray): String {return String(bytes, "windows-1255")}}
Use singleton
FuelManager.instanceto manage global configurations.basePathis used to manage common root path. Great usage is for your static API endpoint.FuelManager.instance.basePath = "https://httpbin.org"​// LaterFuel.get("/get").response { request, response, result ->//make request to https://httpbin.org/get because Fuel.{get|post|put|delete} use FuelManager.instance to make HTTP request}baseHeadersis to manage common HTTP header pairs in format ofMap<String, String>.The base headers are only applied if the request does not have those headers set.
FuelManager.instance.baseHeaders = mapOf("Device" to "Android")
Headerscan be added to a request via various methods includingfun header(name: String, value: Any): Request:request.header("foo", "a")fun header(pairs: Map<String, Any>): Request:request.header(mapOf("foo" to "a"))fun header(vararg pairs: Pair<String, Any>): Request:request.header("foo" to "a")operator fun set(header: String, value: Collection<Any>): Request:request["foo"] = listOf("a", "b")operator fun set(header: String, value: Any): Request:request["foo"] = "a"
By default, all subsequent calls overwrite earlier calls, but you may use the
appendHeadervariant to append values to existing values.In earlier versions a
mapOfoverwrote, andvarargs pairdid not, but this was confusing.
Some of the HTTP headers are defined under
Headers.Companionand can be used instead of literal strings.Fuel.post("/my-post-path").header(Headers.ACCEPT, "text/html, */*; q=0.1").header(Headers.CONTENT_TYPE, "image/png").header(Headers.COOKIE to "basic=very").appendHeader(Headers.COOKIE to "value_1=foo", Headers.COOKIE to "value_2=bar", Headers.ACCEPT to "application/json").appendHeader("MyFoo" to "bar", "MyFoo" to "baz").response { /*...*/ }​// => request with:// Headers:// Accept: "text/html, */*; q=0.1, application/json"// Content-Type: "image/png"// Cookie: "basic=very; value_1=foo; value_2=bar"// MyFoo: "bar, baz"baseParamsis used to manage commonkey=valuequery param, which will be automatically included in all of your subsequent requests in format ofParameters(Anyis converted toStringbytoString()method)FuelManager.instance.baseParams = listOf("api_key" to "1234567890")​// LaterFuel.get("/get").response { request, response, result ->//make request to https://httpbin.org/get?api_key=1234567890}clientis a raw HTTP client driver. Generally, it is responsible to makeRequestintoResponse. Default isHttpClientwhich is a thin wrapper overjava.net.HttpUrlConnection. You could use any httpClient of your choice by conforming toclientprotocol, and set back toFuelManager.instanceto kick off the effect.keyStoreis configurable by user. By default it isnull.socketFactorycan be supplied by user. IfkeyStoreis not null,socketFactorywill be derived from it.hostnameVerifieris configurable by user. By default, it usesHttpsURLConnection.getDefaultHostnameVerifier().requestInterceptorsresponseInterceptorsis a side-effect to add toRequestand/orResponseobjects.For example, one might wanna print cUrlString style for every request that hits server in DEBUG mode.
val manager = FuelManager()if (BUILD_DEBUG) {manager.addRequestInterceptor(cUrlLoggingRequestInterceptor())}val (request, response, result) = manager.request(Method.GET, "https://httpbin.org/get").response() //it will print curl -i -H "Accept-Encoding:compress;q=0.5, gzip;q=1.0" "https://httpbin.org/get"Another example is that you might wanna add data into your Database, you can achieve that with providing
responseInterceptorssuch asinline fun <reified T> DbResponseInterceptor() ={ next: (Request, Response) -> Response ->{ req: Request, res: Response ->val db = DB.getInstance()val instance = Parser.getInstance().parse(res.data, T::class)db.transaction {it.copyToDB(instance)}next(req, res)}}​manager.addResponseInterceptor(DBResponseInterceptor<Dog>)manager.request(Method.GET, "https://www.example.com/api/dog/1").response() // Db interceptor will be called to intercept data and save into Database of your choice
Testing asynchronized calls can be somehow hard without special care. That's why Fuel has a special test mode with make all the requests blocking, for tests.
Fuel.testMode {timeout = 15000 // Optional feature, set all requests' timeout to this value.}
In order to disable test mode, just call Fuel.regularMode()
Fuel supports RxJava right off the box.
"https://www.example.com/photos/1".httpGet().toRxObject(Photo.Deserializer()).subscribe { /* do something */ }There are 6 extensions over
Requestthat provide RxJava 2.xSingle<Result<T, FuelError>>as return type.fun Request.toRxResponse(): Single<Pair<Response, Result<ByteArray, FuelError>>>fun Request.toRxResponseString(charset: Charset): Single<Pair<Response, Result<String, FuelError>>>fun <T : Any> Request.toRxResponseObject(deserializable: Deserializable<T>): Single<Pair<Response, Result<T, FuelError>>>​fun Request.toRxData(): Single<Result<ByteArray, FuelError>>fun Request.toRxString(charset: Charset): Single<Result<String, FuelError>>fun <T : Any> Request.toRxObject(deserializable: Deserializable<T>): Single<Result<T, FuelError>>
Fuel supports LiveData​
Fuel.get("www.example.com/get").liveDataResponse().observe(this) { /* do something */ }
In order to organize better your network stack FuelRouting interface allows you to easily setup a Router design pattern.
sealed class WeatherApi: FuelRouting {​override val basePath = "https://www.metaweather.com"​class weatherFor(val location: String): WeatherApi() {}​override val method: Methodget() {when(this) {is weatherFor -> return Method.GET}}​override val path: Stringget() {return when(this) {is weatherFor -> "/api/location/search/"}}​override val params: Parameters?get() {return when(this) {is weatherFor -> listOf("query" to this.location)}}​override val headers: Map<String, String>?get() {return null}​}​​// UsageFuel.request(WeatherApi.weatherFor("london")).responseJson { request, response, result ->result.fold(success = { json ->Log.d("qdp success", json.array().toString())}, failure = { error ->Log.e("qdp error", error.toString())})}
Coroutines module provides extension functions to wrap a response inside a coroutine and handle its result. The coroutines-based API provides equivalent methods to the standard API (e.g: responseString() in coroutines is awaitStringResponse()).
runBlocking {val (request, response, result) = Fuel.get("https://httpbin.org/ip").awaitStringResponse()​result.fold({ data -> println(data) /* "{"origin":"127.0.0.1"}" */ },{ error -> println("An error of type ${error.exception} happened: ${error.message}") })}
There are functions to handle Result object directly too.
runBlocking {Fuel.get("https://httpbin.org/ip").awaitStringResult().fold({ data -> println(data) /* "{"origin":"127.0.0.1"}" */ },{ error -> println("An error of type ${error.exception} happened: ${error.message}") })}
It also provides useful methods to retrieve the ByteArray,String or Object directly. The difference with these implementations is that they throw exception instead of returning it wrapped a FuelError instance.
runBlocking {try {println(Fuel.get("https://httpbin.org/ip").awaitString()) // "{"origin":"127.0.0.1"}"} catch(exception: Exception) {println("A network request exception was thrown: ${exception.message}")}}
Handling objects other than String (awaitStringResponse()) or ByteArray (awaitByteArrayResponse()) can be done using awaitObject, awaitObjectResult or awaitObjectResponse.
data class Ip(val origin: String)​object IpDeserializer : ResponseDeserializable<Ip> {override fun deserialize(content: String) =jacksonObjectMapper().readValue<Ip>(content)}
runBlocking {Fuel.get("https://httpbin.org/ip").awaitObjectResult(IpDeserializer).fold({ data -> println(data.origin) /* 127.0.0.1 */ },{ error -> println("An error of type ${error.exception} happened: ${error.message}") })}
runBlocking {try {val data = Fuel.get("https://httpbin.org/ip").awaitObject(IpDeserializer)println(data.origin) // 127.0.0.1} catch (exception: Exception) {when (exception){is HttpException -> println("A network request exception was thrown: ${exception.message}")is JsonMappingException -> println("A serialization/deserialization exception was thrown: ${exception.message}")else -> println("An exception [${exception.javaClass.simpleName}\"] was thrown")}}}
The Reactor module API provides functions starting with the prefix mono to handle instances of Response, Result<T, FuelError> and values directly (String, ByteArray, Any). All functions expose exceptions as FuelError instance.
Data handling example
Fuel.get("https://icanhazdadjoke.com").header(Headers.ACCEPT to "text/plain").monoString().subscribe(::println)
Error handling example
data class Guest(val name: String)​object GuestMapper : ResponseDeserializable<Guest> {override fun deserialize(content: String) =jacksonObjectMapper().readValue<Guest>(content)}​Fuel.get("/guestName").monoResultObject(GuestMapper).map(Result<Guest, FuelError>::get).map { (name) -> "Welcome to the party, $name!" }.onErrorReturn("I'm sorry, your name is not on the list.").subscribe(::println)
Response handling example
FuelManager.instance.basePath = "https://httpbin.org"​Fuel.get("/status/404").monoResponse().filter(Response::isSuccessful).switchIfEmpty(Fuel.get("/status/200").monoResponse()).map(Response::statusCode).subscribe(::println)
If you like Fuel, you might also like other libraries of mine;
​Result - The modelling for success/failure of operations in Kotlin
​Fuse - A simple generic LRU memory/disk cache for Android written in Kotlin
​Forge - Functional style JSON parsing written in Kotlin
​ReactiveAndroid - Reactive events and properties with RxJava for Android SDK
Fuel is brought to you by contributors.
Fuel is released under the MIT license.
