Schedule library

A Kotlin library containing a parser and models for Frab-compatible conference schedule JSON (version 1), as used by apps such as:

• https://github.com/EventFahrplan/EventFahrplan

Usage

The library is published as two separate artifacts: schedule-base and schedule-repositories. You can use either of them depending on your needs.

Usage of schedule-base

The schedule-base artifact returns a Response<ScheduleV1> type from the suspending ScheduleService#getScheduleV1 function.

suspend fun loadSchedule(okHttpClient: Call.Factory) {
    val api: ScheduleApi = Api
    val service: ScheduleService = api.provideScheduleService(
        baseUrl = "https://some.event.com/schedules/",
        callFactory = okHttpClient,
    )

    val requestETag = "" // Pass an empty string or a previous ETag value for caching
    val requestLastModifiedAt = "" // Pass an empty string or a previous Last-Modified value for caching
    val response = service.getScheduleV1(
        eTag = requestETag,
        lastModifiedAt = requestLastModifiedAt,
        path = "schedule.json",
    )

    if (response.isSuccessful) {
        val scheduleV1 = response.body()
        val responseETag = response.headers()["ETag"]
        val responseLastModifiedAt = response.headers()["Last-Modified"]
    } else {
        val errorCode = response.code()
        val errorMessage = response.message()
    }
}

Usage of schedule-repositories

The schedule-repositories artifact returns a Flow<GetScheduleV1State> type from the suspending ScheduleRepository#getScheduleV1State function.

suspend fun loadSchedule(okHttpClient: Call.Factory) {
    val repository: ScheduleRepository = SimpleScheduleRepository(
        callFactory = okHttpClient,
        api = Api,
    )

    val requestETag = "" // Pass an empty string or a previous ETag value for caching
    val requestLastModifiedAt = "" // Pass an empty string or a previous Last-Modified value for caching
    repository.getScheduleV1State(
        url = "https://some.event.com/schedules/schedule.json",
        requestETag = requestETag,
        lastModifiedAt = requestLastModifiedAt,
    ).collectLatest { state ->
        when (state) {
            is Success -> {
                val scheduleV1 = state.scheduleV1
                val responseETag = state.responseETag
                val responseLastModifiedAt = state.responseLastModifiedAt
            }
            is Error -> {
                val httpStatusCode = state.httpStatusCode
                val errorMessage = state.errorMessage
            }
            is Failure -> {
                val throwable = state.throwable
            }
        }
    }
}

Gradle build

To deploy the library to your local Maven repository run the following task:

$ ./gradlew publishToMavenLocal

Then, to use the library in your project add the following to your top level build.gradle:

allprojects {
    repositories {
        mavenLocal()
    }
}

and one of the following dependencies to your application module build.gradle:

dependencies {
    implementation "info.metadude.kotlin.library.schedule:schedule-base:$version"
    implementation "info.metadude.kotlin.library.schedule:schedule-repositories:$version"
}

Tests

Run the following command to execute all tests:

$ ./gradlew clean test

Author

• Tobias Preuss

License

Copyright 2026 Tobias Preuss

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.