Igdbclient

Igdbclient is a Kotlin Multiplatform library for fetching information about games from the IGDB.com Video Game Database.

• Can be used with Ktor or Okhttp as an HTTP client
• Implementation of the IGDB v4 API protocol using POST requests and Protobuf as the data encoding format
• Support for Twitch Oauth 2 authentication
• Multi-queries and count-requests
• Configurable automatic retry on HTTP 429 Too Many Requests error
• Helpers for building image URLs using a specified pixel density
• Support for Webhook API
• Android, iOS, Desktop and JavaScript targets

Releases

The latest release is available on Maven Central.

repositories {
    mavenCentral()
}

Dependency when using Кtor client (supported on all targets):

dependencies {
    implementation("ru.pixnews.igdbclient:igdbclient-ktor:0.5")
}

In Kotlin Multiplatform projects, this dependency can be added to the commonMain sourceSet:

commonMain {
    dependencies {
        implementation("ru.pixnews.igdbclient:igdbclient-ktor:0.5")
    }
}

Dependency when using Okhttp (JVM and Android):

dependencies {
    implementation("ru.pixnews.igdbclient:igdbclient-okhttp:0.5")
}

Usage

Create a client to access the API:

val client = IgdbClient(IgdbKtorEngine) {
}

This client is ready to be used to make network requests to the IGDB server. For example, this is a request to fetch games:

val games: GameResult = client.getGames {
    fields(Game.field.all)
    search("Diablo")
}
log.i("games: $games")

Each IGDB API endpoint has a public method defined in the client to fetch data. All the client methods are suspend functions and should be called from the coroutine context.

client.getAgeRatings {…}
client.getAgeRatingContentDescriptions {…}
client.getAlternativeNames {…}
…
client.getThemes {…}
client.getWebsites {…}

Apicalypse query with all the fields:

apicalypseQuery {
    fields(Game.field.id, Game.field.name, Game.field.genres.name)
    exclude("rating")
    where("rating >= 80 & release_dates.date > 631152000")
    search("Diablo")
    sort("release_dates.date", DESC)
    offset(5)
    limit(10)
}

Example of count — query:

val diabloGamesCount = client.executeOrThrow(
    IgdbEndpoint.GAME.countEndpoint(),
    apicalypseQuery {
        fields("*")
        search("Diablo")
    },
) 

log.i { "games count: $diabloGamesCount" }

To make multiple queries in a single request, you can use the client.multiquery():

val response = client.multiquery {
    query(IgdbEndpoint.PLATFORM.countEndpoint(), "Count of Platforms") {}
    query(IgdbEndpoint.GAME, "Playstation Games") {
        fields(Game.field.name, Game.field.category, Game.field.platforms.name)
        limit(5)
    }  
}  
val platformCount = response[0].count
val games = response[1].results as List<Game>?

See https://api-docs.igdb.com/#multi-query for additional info.

Requesting gaming events:

val events = client.getEvents {
    fields(Event.field.all)
    limit(10)
}
logger.i { "events: $events" }

Ktor client

Pass IgdbKtorEngine as the first argument to IgdbClient() when using the Ktor client.
You can pass your own customized Ktor client that will be used to make requests in the httpClient block.

val ktorHttpClient: HttpClient = HttpClient(Java) {
    developmentMode = true
    install(Logging) {
        level = LogLevel.ALL
    }
}

val client = IgdbClient(IgdbKtorEngine) {
    httpClient {
        httpClient = ktorHttpClient
        backgroundDispatcher = Dispatchers.IO
    }
}

Okhttp client

Pass IgdbOkhttpEngine to IgdbClient() when using the Okhttp client.
A pre-configured client can be specified using the callFactory parameter of the httpClient configuration block:

val okhttpClient = OkHttpClient.Builder().apply {
    connectionPool(
        ConnectionPool(
            maxIdleConnections = 8,
            keepAliveDuration = 2000,
            timeUnit = TimeUnit.MILLISECONDS,
        ),
    )
    dispatcher(
        Dispatcher().apply {
            maxRequestsPerHost = 8
        },
    )
}.build()

val client = IgdbClient(IgdbOkhttpEngine) {
    httpClient {
        callFactory = okhttpClient
        backgroundDispatcher = Dispatchers.IO
    }
}

Authentication

Client to server requests

IGDB API does not support making client-to-server requests directly from the mobile and web applications. As a workaround, it is proposed to set up a proxy server that makes requests in server-to-server mode.
IGDB suggests free AWS CloudFormation template as one of the implementations of such a server.

You can set the base URL of the server using the baseUrl parameter, and use the headers block to configure custom headers to authenticate to that server:

val client = IgdbClient(IgdbOkhttpEngine) {  
    baseUrl = "https://<your-api-gateway-unique-id>.execute-api.us-west-2.amazonaws.com/production/v4/"

    headers {
        append("x-api-key", "PROXY_API_KEY")
    }
}

Server to server requests

IGDB API requires authentication using the Twitch OAuth Client Credentials Flow to make server-to-server requests. Additional information can be found on the IGDB documentation page.

You can use the library implementation of the authenticator. To do this, add the twitchAuth configuration block and set the authentication parameters:

val client = IgdbClient(IgdbOkhttpEngine) {
    twitchAuth {
        clientId = "app’s registered client ID"
        clientSecret = "app’s registered client secret."
    }
}

Alternatively, you can implement authentication yourself and pass the received token in the headers:

val client = IgdbClient(IgdbOkhttpEngine) {  
    headers {
        append("Client-ID", "app's Client ID")  
        append("Authorization", "Bearer $received_access_token")  
    }
}

The twitchAuth block should not be defined in the configuration in this case.

Other configuration parameters

HTTP User-Agent header can be customized using the userAgent parameter.
The retryPolicy configuration block is used to set up the request retries on receiving the 429 Too Many Requests HTTP error (enabled by default).

Example:

val client = IgdbClient(IgdbOkhttpEngine) {
    userAgent = "game-client"

    retryPolicy {
        enabled = true
        maxRequestRetries = 100
        initialDelay = 50.milliseconds
        delayRange = Duration.ZERO..2.minutes
        jitterFactor = 0.1f
    }
}

Image Builder

igdbImageUrl helper function can be used to generate an image URL for a given image type and pixel density according to the documentation https://api-docs.igdb.com/#images.

Example:

val url = igdbImageUrl(
    imageId = "em1y2ugcwy2myuhvb9db",
    imageSize = LOGO_MEDIUM,
    imageFormat = IgdbImageFormat.JPEG,
    size2x = true,
)
// url: https://images.igdb.com/igdb/image/upload/t_logo_med_2x/em1y2ugcwy2myuhvb9db.jpg

R8 / ProGuard

This library does not require any special R8 rules, but the used HTTP client may need its own rules. Check the setup instructions for your client:

• Okhttp: https://square.github.io/okhttp/features/r8_proguard/
• Ktor: https://ktor.io/docs/client-dependencies.html

Contributing

Any type of contributions are welcome. Please see the contribution guide.

The following types of contributions are especially welcome:

• Additions and corrections to documentation
• Suggestions for refactoring and improving the API
• New feature proposals (only for this library only, not the parent IGDB API)

License

This library uses the IGDB but is not endorsed or certified by IGDB.
These services are licensed under Apache 2.0 License.
Authors and contributors are listed in the Authors file.

Copyright 2023 Igdbclient project authors and contributors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.