Kotlin: Installing

Add one or more modules to your project

Add dependency to your build file using the BOM.

The available modules are:

Check out the different READMEs for information about supported Kotlin targets.

Note that the minimum Android SDK version is 26. For lower versions, you need to enable core library desugaring.

implementation(platform("io.github.jan-tennert.supabase:bom:VERSION"))
implementation("io.github.jan-tennert.supabase:postgrest-kt")
implementation("io.github.jan-tennert.supabase:auth-kt")
implementation("io.github.jan-tennert.supabase:realtime-kt")

implementation platform("io.github.jan-tennert.supabase:bom:VERSION")
implementation 'io.github.jan-tennert.supabase:postgrest-kt'
implementation 'io.github.jan-tennert.supabase:auth-kt'
implementation 'io.github.jan-tennert.supabase:realtime-kt'

<dependency>
    <groupId>io.github.jan-tennert.supabase</groupId>
    <artifactId>bom</artifactId>
    <version>VERSION</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>
<dependency>
    <groupId>io.github.jan-tennert.supabase</groupId>
    <artifactId>postgrest-kt</artifactId>
</dependency>
<dependency>
    <groupId>io.github.jan-tennert.supabase</groupId>
    <artifactId>auth-kt</artifactId>
</dependency>
<dependency>
    <groupId>io.github.jan-tennert.supabase</groupId>
    <artifactId>realtime-kt</artifactId>
</dependency>

Add Ktor Client Engine to each of your Kotlin targets (required)

You can find a list of engines here

implementation("io.ktor:ktor-client-[engine]:KTOR_VERSION")

implementation 'io.ktor:ktor-client-[engine]:KTOR_VERSION'

<dependency>
    <groupId>io.ktor</groupId>
    <artifactId>ktor-client-[engine]</artifactId>
    <version>KTOR_VERSION</version>
</dependency>

Multiplatform example:

commonMain {
    dependencies {
        //Supabase modules
    }
}
jvmMain {
    dependencies {
        implementation("io.ktor:ktor-client-cio:KTOR_VERSION")
    }
}
androidMain {
    dependsOn(jvmMain.get())
}
jsMain {
    dependencies {
        implementation("io.ktor:ktor-client-js:KTOR_VERSION")
    }
}
iosMain {
    dependencies {
        implementation("io.ktor:ktor-client-darwin:KTOR_VERSION")
    }
}

Serialization

supabase-kt provides several different ways to encode and decode your custom objects. By default, KotlinX Serialization is used.

Use KotlinX Serialization.

plugins {
    kotlin("plugin.serialization") version "KOTLIN_VERSION"
}

plugins {
    id 'org.jetbrains.kotlin.plugin.serialization' version 'KOTLIN_VERSION'
}

<build>
    <plugins>
        <plugin>
            <groupId>org.jetbrains.kotlin</groupId>
            <artifactId>kotlin-maven-plugin</artifactId>
            <version>${kotlin.version}</version>
            <executions>
                <execution>
                    <id>compile</id>
                    <phase>compile</phase>
                    <goals>
                        <goal>compile</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <compilerPlugins>
                    <plugin>kotlinx-serialization</plugin>
                </compilerPlugins>
            </configuration>
            <dependencies>
                <dependency>
                    <groupId>org.jetbrains.kotlin</groupId>
                    <artifactId>kotlin-maven-serialization</artifactId>
                    <version>${kotlin.version}</version>
                </dependency>
            </dependencies>
        </plugin>
    </plugins>
</build>

val supabase = createSupabaseClient(supabaseUrl, supabaseKey) {
    //Already the default serializer, but you can provide a custom Json instance (optional):
    defaultSerializer = KotlinXSerializer(Json {
        //apply your custom config
    })
}

Use Moshi.

implementation("io.github.jan-tennert.supabase:serializer-moshi:VERSION")

implementation 'io.github.jan-tennert.supabase:serializer-moshi:VERSION'

<dependency>
    <groupId>io.github.jan-tennert.supabase</groupId>
    <artifactId>serializer-moshi</artifactId>
    <version>VERSION</version>
</dependency>

val supabase = createSupabaseClient(supabaseUrl, supabaseKey) {
    defaultSerializer = MoshiSerializer()
}

Use Jackson.

implementation("io.github.jan-tennert.supabase:serializer-jackson:VERSION")

implementation 'io.github.jan-tennert.supabase:serializer-jackson:VERSION'

<dependency>
    <groupId>io.github.jan-tennert.supabase</groupId>
    <artifactId>serializer-jackson</artifactId>
    <version>VERSION</version>
</dependency>

val supabase = createSupabaseClient(supabaseUrl, supabaseKey) {
    defaultSerializer = JacksonSerializer()
}

Use custom serializer.

class CustomSerializer: SupabaseSerializer {

    override fun <T : Any> encode(type: KType, value: T): String {
        //encode value to string
    }

    override fun <T : Any> decode(type: KType, value: String): T {
        //decode value
    }

}

val supabase = createSupabaseClient(supabaseUrl, supabaseKey) {
    defaultSerializer = CustomSerializer()
}

Enable Data API access

supabase-kt uses the Data API to query and mutate your Postgres data. You first need to grant Data API roles permissions to access your tables and functions.

In Data API integrations settings, expose the specific tables and functions you want to access. To automatically grant access for new tables and functions in public, enable Default privileges for new entities.

Alternatively, use SQL to grant the required permissions:

-- Before granting access to client roles, make sure RLS is enabled
-- and create the policies required for each role's allowed operations.
alter table public.your_table enable row level security;
-- create policy ... on public.your_table ...;

-- Grant least-privilege access to tables after RLS and policies are in place
grant select on public.your_table to anon;
grant select, insert, update, delete on public.your_table to authenticated;
grant all on public.your_table to service_role;

-- Grant execute on functions after verifying any table access they rely on
grant execute on function public.your_function to authenticated, service_role;