Enforce unidirectional arch better

app/src/main/java/org/mozilla/fenix/components/Core.kt

@@ -8,7 +8,6 @@ import android.content.Context
 import android.content.SharedPreferences
 import android.preference.PreferenceManager
 import mozilla.components.browser.engine.gecko.GeckoEngine
-import mozilla.components.browser.session.Session
 import mozilla.components.browser.session.SessionManager
 import mozilla.components.browser.session.storage.SessionStorage
 import mozilla.components.browser.storage.sync.PlacesHistoryStorage
@@ -19,7 +18,6 @@ import mozilla.components.feature.session.HistoryDelegate
 import mozilla.components.lib.crash.handler.CrashHandlerService
 import org.mozilla.geckoview.GeckoRuntime
 import org.mozilla.geckoview.GeckoRuntimeSettings
-import java.util.concurrent.TimeUnit
 
 /**
  * Component group for all core browser functionality.

app/src/main/java/org/mozilla/fenix/home/sessions/SessionsComponent.kt

@@ -4,10 +4,8 @@
 
 package org.mozilla.fenix.home.sessions
 
-import android.annotation.SuppressLint
 import android.view.ViewGroup
 import mozilla.components.browser.session.Session
-import mozilla.components.support.base.log.logger.Logger
 import org.mozilla.fenix.mvi.Action
 import org.mozilla.fenix.mvi.ActionBusFactory
 import org.mozilla.fenix.mvi.Change
@@ -16,10 +14,13 @@ import org.mozilla.fenix.mvi.ViewState
 
 class SessionsComponent(
     private val container: ViewGroup,
-    override val bus: ActionBusFactory,
+    bus: ActionBusFactory,
     override var initialState: SessionsState = SessionsState(emptyList())
 ) :
-    UIComponent<SessionsState, SessionsAction, SessionsChange>(bus) {
+    UIComponent<SessionsState, SessionsAction, SessionsChange>(
+        bus.getManagedEmitter(SessionsAction::class.java),
+        bus.getSafeManagedObservable(SessionsChange::class.java)
+    ) {
 
     override val reducer: (SessionsState, SessionsChange) -> SessionsState = { state, change ->
         when (change) {
@@ -27,20 +28,10 @@ class SessionsComponent(
         }
     }
 
-    override fun initView() = SessionsUIView(container, bus)
+    override fun initView() = SessionsUIView(container, actionEmitter, changesObservable)
 
     init {
-        setup()
-    }
-
-    @SuppressLint("CheckResult")
-    fun setup(): SessionsComponent {
         render(reducer)
-        getUserInteractionEvents<SessionsAction>()
-            .subscribe {
-                Logger("SessionsComponent").debug(it.toString())
-            }
-        return this
     }
 }
 

app/src/main/java/org/mozilla/fenix/home/sessions/SessionsUIView.kt

@@ -8,13 +8,18 @@ import android.view.LayoutInflater
 import android.view.ViewGroup
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
+import io.reactivex.Observable
+import io.reactivex.Observer
 import io.reactivex.functions.Consumer
 import org.mozilla.fenix.R
-import org.mozilla.fenix.mvi.ActionBusFactory
 import org.mozilla.fenix.mvi.UIView
 
-class SessionsUIView(container: ViewGroup, bus: ActionBusFactory) :
-    UIView<SessionsState>(container, bus) {
+class SessionsUIView(
+    container: ViewGroup,
+    actionEmitter: Observer<SessionsAction>,
+    changesObservable: Observable<SessionsChange>
+) :
+    UIView<SessionsState, SessionsAction, SessionsChange>(container, actionEmitter, changesObservable) {
 
     override val view: RecyclerView = LayoutInflater.from(container.context)
         .inflate(R.layout.component_sessions, container, true)

app/src/main/java/org/mozilla/fenix/mvi/ActionBusFactory.kt

@@ -27,6 +27,7 @@ import androidx.lifecycle.LifecycleObserver
 import androidx.lifecycle.LifecycleOwner
 import androidx.lifecycle.OnLifecycleEvent
 import io.reactivex.Observable
+import io.reactivex.Observer
 import io.reactivex.rxkotlin.merge
 import io.reactivex.subjects.PublishSubject
 import io.reactivex.subjects.Subject
@@ -102,6 +103,10 @@ class ActionBusFactory private constructor(val owner: LifecycleOwner) {
         return if (map[clazz] != null) map[clazz] as Observable<T> else create(clazz)
     }
 
+    fun <T : Action> getManagedEmitter(clazz: Class<T>): Observer<T> {
+        return if (map[clazz] != null) map[clazz] as Observer<T> else create(clazz)
+    }
+
     fun logMergedObservables() {
         // TODO make this observe new items in the map and combine them
         map.values.merge().compose(logState()).subscribe()
@@ -131,6 +136,9 @@ inline fun <reified T : Action> LifecycleOwner.emit(event: T) =
 inline fun <reified T : Action> LifecycleOwner.getSafeManagedObservable(): Observable<T> =
     ActionBusFactory.get(this).getSafeManagedObservable(T::class.java)
 
+inline fun <reified T : Action> LifecycleOwner.getManagedEmitter(): Observer<T> =
+    ActionBusFactory.get(this).getManagedEmitter(T::class.java)
+
 /**
  * This method returns a destroy observable that can be passed to [org.mozilla.fenix.mvi.UIView]s as needed.
  * This is deliberately scoped to the attached [LifecycleOwner]'s [Lifecycle.Event.ON_DESTROY]

app/src/main/java/org/mozilla/fenix/mvi/UIComponent.kt

@@ -5,29 +5,28 @@
 package org.mozilla.fenix.mvi
 
 import io.reactivex.Observable
+import io.reactivex.Observer
 import io.reactivex.android.schedulers.AndroidSchedulers
 import io.reactivex.disposables.Disposable
 import io.reactivex.schedulers.Schedulers
 
-abstract class UIComponent<S : ViewState, A : Action, C : Change>(open val bus: ActionBusFactory) {
+abstract class UIComponent<S : ViewState, A : Action, C : Change>(
+    protected val actionEmitter: Observer<A>,
+    protected val changesObservable: Observable<C>
+) {
+
     abstract var initialState: S
     abstract val reducer: Reducer<S, C>
-    val uiView: UIView<S> by lazy { initView() }
+    val uiView: UIView<S, A, C> by lazy { initView() }
 
-    abstract fun initView(): UIView<S>
+    abstract fun initView(): UIView<S, A, C>
     open fun getContainerId() = uiView.containerId
 
-    inline fun <reified A : Action> getUserInteractionEvents():
-            Observable<A> = bus.getSafeManagedObservable(A::class.java)
-
-    inline fun <reified C : Change> getModelChangeEvents():
-            Observable<C> = bus.getSafeManagedObservable(C::class.java)
-
     /**
      * Render the ViewState to the View through the Reducer
      */
-    inline fun <reified C : Change> render(noinline reducer: Reducer<S, C>): Disposable =
-        getModelChangeEvents<C>()
+    fun render(reducer: Reducer<S, C>): Disposable =
+        changesObservable
             .scan(initialState, reducer)
             .distinctUntilChanged()
             .subscribeOn(Schedulers.io())

app/src/main/java/org/mozilla/fenix/mvi/UIView.kt

@@ -7,12 +7,15 @@ package org.mozilla.fenix.mvi
 import android.view.View
 import android.view.ViewGroup
 import androidx.annotation.IdRes
+import io.reactivex.Observable
+import io.reactivex.Observer
 import io.reactivex.functions.Consumer
 import kotlinx.android.extensions.LayoutContainer
 
-abstract class UIView<S : ViewState>(
+abstract class UIView<S : ViewState, A : Action, C : Change>(
     private val container: ViewGroup,
-    val bus: ActionBusFactory
+    protected val actionEmitter: Observer<A>,
+    protected val changesObservable: Observable<C>
 ) : LayoutContainer {
 
     abstract val view: View

app/src/main/java/org/mozilla/fenix/search/SearchFragment.kt

@@ -4,6 +4,7 @@
 
 package org.mozilla.fenix.search
 
+import android.annotation.SuppressLint
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
@@ -13,10 +14,13 @@ import androidx.navigation.Navigation
 import kotlinx.android.synthetic.main.fragment_search.view.*
 import org.mozilla.fenix.R
 import org.mozilla.fenix.mvi.ActionBusFactory
+import org.mozilla.fenix.mvi.getSafeManagedObservable
 import org.mozilla.fenix.search.awesomebar.AwesomeBarAction
 import org.mozilla.fenix.search.awesomebar.AwesomeBarChange
 import org.mozilla.fenix.search.awesomebar.AwesomeBarComponent
-import org.mozilla.fenix.search.toolbar.*
+import org.mozilla.fenix.search.toolbar.SearchAction
+import org.mozilla.fenix.search.toolbar.ToolbarComponent
+import org.mozilla.fenix.search.toolbar.ToolbarUIView
 
 class SearchFragment : Fragment() {
     private lateinit var toolbarComponent: ToolbarComponent
@@ -30,6 +34,7 @@ class SearchFragment : Fragment() {
         val view = inflater.inflate(R.layout.fragment_search, container, false)
         toolbarComponent = ToolbarComponent(view.toolbar_wrapper, ActionBusFactory.get(this))
         awesomeBarComponent = AwesomeBarComponent(view.search_layout, ActionBusFactory.get(this))
+        ActionBusFactory.get(this).logMergedObservables()
         return view
     }
 
@@ -38,6 +43,7 @@ class SearchFragment : Fragment() {
         toolbarComponent.editMode()
     }
 
+    @SuppressLint("CheckResult")
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
 
@@ -47,26 +53,18 @@ class SearchFragment : Fragment() {
 
         view.toolbar_wrapper.clipToOutline = false
 
-        toolbarComponent
-            .getModelChangeEvents<SearchChange>()
+        getSafeManagedObservable<SearchAction>()
             .subscribe {
                 when (it) {
-                    is SearchChange.QueryChanged -> {
-                        ActionBusFactory.get(this).emit(AwesomeBarChange::class.java, AwesomeBarChange.UpdateQuery(it.query))
+                    is SearchAction.UrlCommitted -> transitionToBrowser()
+                    is SearchAction.TextChanged -> {
+                        ActionBusFactory.get(this)
+                            .emit(AwesomeBarChange::class.java, AwesomeBarChange.UpdateQuery(it.query))
                     }
                 }
             }
 
-        toolbarComponent
-            .getUserInteractionEvents<SearchAction>()
-            .subscribe {
-                when (it) {
-                    is SearchAction.UrlCommitted -> transitionToBrowser()
-                }
-            }
-
-        awesomeBarComponent
-            .getUserInteractionEvents<AwesomeBarAction>()
+        getSafeManagedObservable<AwesomeBarAction>()
             .subscribe {
                 when (it) {
                     is AwesomeBarAction.ItemSelected -> transitionToBrowser()

app/src/main/java/org/mozilla/fenix/search/awesomebar/AwesomeBarComponent.kt

@@ -4,32 +4,38 @@ package org.mozilla.fenix.search.awesomebar
    file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 import android.view.ViewGroup
-import org.mozilla.fenix.mvi.*
+import org.mozilla.fenix.mvi.Action
+import org.mozilla.fenix.mvi.ActionBusFactory
+import org.mozilla.fenix.mvi.Change
+import org.mozilla.fenix.mvi.Reducer
+import org.mozilla.fenix.mvi.UIComponent
+import org.mozilla.fenix.mvi.ViewState
 
-data class AwesomeBarState(val query: String) : ViewState {
-    fun updateQuery(query: String) = AwesomeBarState(query)
-}
+data class AwesomeBarState(val query: String) : ViewState
 
-sealed class AwesomeBarAction: Action {
-    object ItemSelected: AwesomeBarAction()
+sealed class AwesomeBarAction : Action {
+    object ItemSelected : AwesomeBarAction()
 }
 
 sealed class AwesomeBarChange : Change {
-    data class UpdateQuery(val query: String): AwesomeBarChange()
+    data class UpdateQuery(val query: String) : AwesomeBarChange()
 }
 
 class AwesomeBarComponent(
     private val container: ViewGroup,
-    override val bus: ActionBusFactory,
+    bus: ActionBusFactory,
     override var initialState: AwesomeBarState = AwesomeBarState("")
-) : UIComponent<AwesomeBarState, AwesomeBarAction, AwesomeBarChange>(bus) {
+) : UIComponent<AwesomeBarState, AwesomeBarAction, AwesomeBarChange>(
+    bus.getManagedEmitter(AwesomeBarAction::class.java),
+    bus.getSafeManagedObservable(AwesomeBarChange::class.java)
+) {
     override val reducer: Reducer<AwesomeBarState, AwesomeBarChange> = { state, change ->
         when (change) {
-            is AwesomeBarChange.UpdateQuery -> state.updateQuery(change.query)
+            is AwesomeBarChange.UpdateQuery -> state.copy(query = change.query)
         }
     }
 
-    override fun initView() = AwesomeBarUIView(container, bus)
+    override fun initView() = AwesomeBarUIView(container, actionEmitter, changesObservable)
 
     init {
         render(reducer)

app/src/main/java/org/mozilla/fenix/search/awesomebar/AwesomeBarUIView.kt

@@ -5,6 +5,8 @@ package org.mozilla.fenix.search.awesomebar
 
 import android.view.LayoutInflater
 import android.view.ViewGroup
+import io.reactivex.Observable
+import io.reactivex.Observer
 import io.reactivex.functions.Consumer
 import mozilla.components.browser.awesomebar.BrowserAwesomeBar
 import mozilla.components.feature.awesomebar.provider.ClipboardSuggestionProvider
@@ -13,11 +15,14 @@ import mozilla.components.feature.awesomebar.provider.SessionSuggestionProvider
 import mozilla.components.support.ktx.android.graphics.drawable.toBitmap
 import org.mozilla.fenix.R
 import org.mozilla.fenix.ext.components
-import org.mozilla.fenix.mvi.ActionBusFactory
 import org.mozilla.fenix.mvi.UIView
 
-class AwesomeBarUIView(container: ViewGroup, bus: ActionBusFactory) :
-    UIView<AwesomeBarState>(container, bus) {
+class AwesomeBarUIView(
+    container: ViewGroup,
+    actionEmitter: Observer<AwesomeBarAction>,
+    changesObservable: Observable<AwesomeBarChange>
+) :
+    UIView<AwesomeBarState, AwesomeBarAction, AwesomeBarChange>(container, actionEmitter, changesObservable) {
     override val view: BrowserAwesomeBar = LayoutInflater.from(container.context)
         .inflate(R.layout.component_awesomebar, container, true)
         .findViewById(R.id.awesomeBar)
@@ -31,18 +36,19 @@ class AwesomeBarUIView(container: ViewGroup, bus: ActionBusFactory) :
                 getString(R.string.awesomebar_clipboard_title)
                 )
             )
-            view.addProviders(SessionSuggestionProvider(components.core.sessionManager, components.useCases.tabsUseCases.selectTab))
+            view.addProviders(SessionSuggestionProvider(components.core.sessionManager,
+                components.useCases.tabsUseCases.selectTab))
             view.addProviders(SearchSuggestionProvider(
                 components.search.searchEngineManager.getDefaultSearchEngine(this),
                 components.useCases.searchUseCases.defaultSearch,
                 SearchSuggestionProvider.Mode.MULTIPLE_SUGGESTIONS)
             )
 
-            view.setOnStopListener { bus.emit(AwesomeBarAction::class.java, AwesomeBarAction.ItemSelected) }
+            view.setOnStopListener { actionEmitter.onNext(AwesomeBarAction.ItemSelected) }
         }
     }
 
     override fun updateView() = Consumer<AwesomeBarState> {
         view.onInputChanged(it.query)
     }
-}
+}

app/src/main/java/org/mozilla/fenix/search/toolbar/ToolbarComponent.kt

@@ -16,18 +16,21 @@ import org.mozilla.fenix.mvi.ViewState
 
 class ToolbarComponent(
     private val container: ViewGroup,
-    override val bus: ActionBusFactory,
+    bus: ActionBusFactory,
     override var initialState: SearchState = SearchState("")
 ) :
-    UIComponent<SearchState, SearchAction, SearchChange>(bus) {
+    UIComponent<SearchState, SearchAction, SearchChange>(
+        bus.getManagedEmitter(SearchAction::class.java),
+        bus.getSafeManagedObservable(SearchChange::class.java)
+    ) {
 
     override val reducer: Reducer<SearchState, SearchChange> = { state, change ->
         when (change) {
-            is SearchChange.QueryChanged -> state.updateQuery(change.query)
+            is SearchChange.QueryChanged -> state.copy(query = change.query)
         }
     }
 
-    override fun initView() = ToolbarUIView(container, bus)
+    override fun initView() = ToolbarUIView(container, actionEmitter, changesObservable)
     init {
         render(reducer)
     }
@@ -36,12 +39,11 @@ class ToolbarComponent(
     fun editMode() = getView().editMode()
 }
 
-data class SearchState(val query: String) : ViewState {
-    fun updateQuery(query: String) = SearchState(query)
-}
+data class SearchState(val query: String) : ViewState
 
 sealed class SearchAction : Action {
-    data class UrlCommitted(val url: String): SearchAction()
+    data class UrlCommitted(val url: String) : SearchAction()
+    data class TextChanged(val query: String) : SearchAction()
 }
 
 sealed class SearchChange : Change {

app/src/main/java/org/mozilla/fenix/search/toolbar/ToolbarUIView.kt

@@ -7,6 +7,8 @@ package org.mozilla.fenix.search.toolbar
 import android.view.LayoutInflater
 import android.view.ViewGroup
 import androidx.core.content.ContextCompat
+import io.reactivex.Observable
+import io.reactivex.Observer
 import io.reactivex.functions.Consumer
 import mozilla.components.browser.domains.autocomplete.ShippedDomainsProvider
 import mozilla.components.browser.toolbar.BrowserToolbar
@@ -14,12 +16,14 @@ import mozilla.components.support.ktx.android.content.res.pxToDp
 import org.mozilla.fenix.R
 import org.mozilla.fenix.components.toolbar.ToolbarIntegration
 import org.mozilla.fenix.ext.components
-import org.mozilla.fenix.ext.requireComponents
-import org.mozilla.fenix.mvi.ActionBusFactory
 import org.mozilla.fenix.mvi.UIView
 
-class ToolbarUIView(container: ViewGroup, bus: ActionBusFactory) :
-    UIView<SearchState>(container, bus) {
+class ToolbarUIView(
+    container: ViewGroup,
+    actionEmitter: Observer<SearchAction>,
+    changesObservable: Observable<SearchChange>
+) :
+    UIView<SearchState, SearchAction, SearchChange>(container, actionEmitter, changesObservable) {
 
     val toolbarIntegration: ToolbarIntegration
 
@@ -33,7 +37,7 @@ class ToolbarUIView(container: ViewGroup, bus: ActionBusFactory) :
     init {
         view.apply {
             onUrlClicked = { false }
-            setOnUrlCommitListener { bus.emit(SearchAction::class.java, SearchAction.UrlCommitted(it)) }
+            setOnUrlCommitListener { actionEmitter.onNext(SearchAction.UrlCommitted(it)) }
 
             browserActionMargin = resources.pxToDp(browserActionMarginDp)
             urlBoxView = urlBackground
@@ -46,11 +50,11 @@ class ToolbarUIView(container: ViewGroup, bus: ActionBusFactory) :
 
             setOnEditListener(object : mozilla.components.concept.toolbar.Toolbar.OnEditListener {
                 override fun onTextChanged(text: String) {
-                    bus.emit(SearchChange::class.java, SearchChange.QueryChanged(text))
+                    actionEmitter.onNext(SearchAction.TextChanged(text))
                 }
 
                 override fun onStopEditing() {
-                    bus.emit(SearchAction::class.java, SearchAction.UrlCommitted("foo"))
+                    actionEmitter.onNext(SearchAction.UrlCommitted("foo"))
                 }
             })
         }