SLF4J VS RxJava

A few years ago, my team moved from Java to Go. Working on Go projects, we encountered a wide variety of logging frameworks with different APIs, configuration, and formatting. We soon found ourselves longing for a logging abstraction layer like Java’s slf4j, which had proven invaluable for use in reusable libraries or configuring and debugging production systems. So, not long after moving to Go, we began working toward replacing what we had lost in slf4j.

I'm not familiar with Serilog as I code mostly in Java, use slf4j (logs to stdout) and our apps send logs to Cloudwatch using the task definition's awslogs configuration. I prefer it this way because I can customize the log configurations in my task definitions. Also the default stream name has this format prefix-name/container-name/ecs-task-id so I can easily identify the logs of the task I want to look at. I haven't experienced any downsides with this approach and our apps publish a shit ton of logs. Cloudwatch approach looks like you can customize the stream name?

slf4j is open source. You can look at the code.

Java -> Logback, Log4j2, JDK (Java Util Logging), Slf4j, e.t.c.

slf4j para padronização dos logs;

SLF4J

> My God. Logging in protobuf?

Yes, or any other data format and/or transport protocol.

I'm surprised this is up for debate.

> Logging is the lowest of all debugging utilities - its the first thing you ever do writing software - “hello world”. And, while I admire structural logging, the truth is printing strings remains (truly) the lowest common denominator across software developers.

This sort of comment is terribly miopic. You can have a logging API, and then configure your logging to transport the events anywhere, any way. This is a terribly basic feature and requirement, and one that comes out of the box with some systems. Check how SLF4J[1] is pervasive in Java, and how any SLF4J implementation offers logging to stdout or a local file as a very specific and basic usecase.

It turns out that nowadays most developers write software that runs on many computers that aren't stashed over or under their desks, and thus they need efficient and convenient ways to check what's happening either in a node or in all deployments.

[1] https://www.slf4j.org/

Is this similar RxJava, the reactive extensions library for https://github.com/ReactiveX/RxJava ? I have made that work in Clojure in production.

Since you mentioned java, there is RxJava and RxAndroid. Google general recommendation now is to use kotlin coroutines if you're considering writing your app with that.

It's very quick though. In terms of the correctness of the syntax, I've never seen an issue while translating a single file or a single function. When I took the entire RxJava code base 5 years ago, right clicked on the source folder and converted to Kotlin, I found lots of problems. File by file I've never seen any issues though, but I also haven't done it much.

You all beat me to MapStruct and Testcontainers. Honorable mention to RxJava, which I use in Desktop apps.

RxJava with RxRelay (and rx-combinetuple-kt)

RxJava2

More information about rxJava, check it out here: (HERE)[https://github.com/ReactiveX/RxJava]

Concurrency: Kotlin coroutines for general use, Rx or Flow for reactive programming (you can technically use Rx for regular concurrency as well, but not really what it's meant for)

If you're just looking at making a service call on a regular interval and notifying the user when there's an actual change in data, you can also look into RxJava https://github.com/ReactiveX/RxJava. From here you can "subscribe" to your service call, and then every time you make your service call you can have it look for changes compared to the previous emission .distinctUntilChanged() and then only notify it's subscribers when it notices an actual change. From there you can trigger a local notification and push to a LiveData (assuming MVVM) or otherwise update the UI to match as well.

``` io.reactivex.rxjava3.exceptions.OnErrorNotImplementedException: The exception was not handled due to missing onError handler in the subscribe() method call. Further reading: https://github.com/ReactiveX/RxJava/wiki/Error-Handling | java.lang.IllegalStateException: Migration didn't properly handle: feed_group(org.schabi.newpipe.database.feed.model.FeedGroupEntity). Expected: TableInfo{name='feed_group', columns={name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}}, foreignKeys=[], indices=[Index{name='index_feed_group_sort_order', unique=false, columns=[sort_order]}]} Found: TableInfo{name='feed_group', columns={uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='0'}}, foreignKeys=[], indices=[]} at io.reactivex.rxjava3.internal.functions.Functions$OnErrorMissingConsumer.accept(Functions.java:717) at io.reactivex.rxjava3.internal.functions.Functions$OnErrorMissingConsumer.accept(Functions.java:714) at io.reactivex.rxjava3.internal.subscribers.LambdaSubscriber.onError(LambdaSubscriber.java:79) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$BaseObserveOnSubscriber.checkTerminated(FlowableObserveOn.java:209) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$ObserveOnSubscriber.runAsync(FlowableObserveOn.java:394) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$BaseObserveOnSubscriber.run(FlowableObserveOn.java:176) at io.reactivex.rxjava3.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:123) at android.os.Handler.handleCallback(Handler.java:938) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:223) at android.app.ActivityThread.main(ActivityThread.java:7665) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:594) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947) Caused by: java.lang.IllegalStateException: Migration didn't properly handle: feed_group(org.schabi.newpipe.database.feed.model.FeedGroupEntity). Expected: TableInfo{name='feed_group', columns={name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}}, foreignKeys=[], indices=[Index{name='index_feed_group_sort_order', unique=false, columns=[sort_order]}]} Found: TableInfo{name='feed_group', columns={uid=Column{name='uid', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=1, defaultValue='null'}, name=Column{name='name', type='TEXT', affinity='2', notNull=true, primaryKeyPosition=0, defaultValue='null'}, icon_id=Column{name='icon_id', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='null'}, sort_order=Column{name='sort_order', type='INTEGER', affinity='3', notNull=true, primaryKeyPosition=0, defaultValue='0'}}, foreignKeys=[], indices=[]} at androidx.room.RoomOpenHelper.onUpgrade(RoomOpenHelper.java:103) at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.onUpgrade(FrameworkSQLiteOpenHelper.java:177) at android.database.sqlite.SQLiteOpenHelper.getDatabaseLocked(SQLiteOpenHelper.java:416) at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:316) at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper$OpenHelper.getWritableSupportDatabase(FrameworkSQLiteOpenHelper.java:145) at androidx.sqlite.db.framework.FrameworkSQLiteOpenHelper.getWritableDatabase(FrameworkSQLiteOpenHelper.java:106) at androidx.room.RoomDatabase.inTransaction(RoomDatabase.java:622) at androidx.room.RoomDatabase.assertNotSuspendingTransaction(RoomDatabase.java:399) at androidx.room.RoomDatabase.query(RoomDatabase.java:442) at androidx.room.util.DBUtil.query(DBUtil.java:83) at org.schabi.newpipe.database.feed.dao.FeedDAO_Impl$7.call(FeedDAO_Impl.java:285) at org.schabi.newpipe.database.feed.dao.FeedDAO_Impl$7.call(FeedDAO_Impl.java:282) at io.reactivex.rxjava3.internal.operators.maybe.MaybeFromCallable.subscribeActual(MaybeFromCallable.java:47) at io.reactivex.rxjava3.core.Maybe.subscribe(Maybe.java:5330) at io.reactivex.rxjava3.internal.operators.flowable.FlowableFlatMapMaybe$FlatMapMaybeSubscriber.onNext(FlowableFlatMapMaybe.java:131) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$ObserveOnSubscriber.runAsync(FlowableObserveOn.java:402) at io.reactivex.rxjava3.internal.operators.flowable.FlowableObserveOn$BaseObserveOnSubscriber.run(FlowableObserveOn.java:176) at io.reactivex.rxjava3.internal.schedulers.ExecutorScheduler$ExecutorWorker$BooleanRunnable.run(ExecutorScheduler.java:322) at io.reactivex.rxjava3.internal.schedulers.ExecutorScheduler$ExecutorWorker.runEager(ExecutorScheduler.java:287) at io.reactivex.rxjava3.internal.schedulers.ExecutorScheduler$ExecutorWorker.run(ExecutorScheduler.java:248) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641) at java.lang.Thread.run(Thread.java:923)