**! ! Warning**: Do not merge before testing every API call and database
read involving JSON !
**Gson** is obsolete and has been superseded by **Moshi**. But more
importantly, parsing Kotlin objects using Gson is _dangerous_ because
Gson uses Java serialization and is **not Kotlin-aware**. This has two
main consequences:
- Fields of non-null types may end up null at runtime. Parsing will
succeed, but the code may crash later with a `NullPointerException` when
trying to access a field member;
- Default values of constructor parameters are always ignored. When
absent, reference types will be null, booleans will be false and
integers will be zero.
On the other hand, Kotlin-aware parsers like **Moshi** or **Kotlin
Serialization** will validate at parsing time that all received fields
comply with the Kotlin contract and avoid errors at runtime, making apps
more stable and schema mismatches easier to detect (as long as logs are
accessible):
- Receiving a null value for a non-null type will generate a parsing
error;
- Optional types are declared explicitly by adding a default value. **A
missing value with no default value declaration will generate a parsing
error.**
Migrating the entity declarations from Gson to Moshi will make the code
more robust but is not an easy task because of the semantic differences.
With Gson, both nullable and optional fields are represented with a null
value. After converting to Moshi, some nullable entities can become
non-null with a default value (if they are optional and not nullable),
others can stay nullable with no default value (if they are mandatory
and nullable), and others can become **nullable with a default value of
null** (if they are optional _or_ nullable _or_ both). That third option
is the safest bet when it's not clear if a field is optional or not,
except for lists which can usually be declared as non-null with a
default value of an empty list (I have yet to see a nullable array type
in the Mastodon API).
Fields that are currently declared as non-null present another
challenge. In theory, they should remain as-is and everything will work
fine. In practice, **because Gson is not aware of nullable types at
all**, it's possible that some non-null fields currently hold a null
value in some cases but the app does not report any error because the
field is not accessed by Kotlin code in that scenario. After migrating
to Moshi however, parsing such a field will now fail early if a null
value or no value is received.
These fields will have to be identified by heavily testing the app and
looking for parsing errors (`JsonDataException`) and/or by going through
the Mastodon documentation. A default value needs to be added for
missing optional fields, and their type could optionally be changed to
nullable, depending on the case.
Gson is also currently used to serialize and deserialize objects to and
from the local database, which is also challenging because backwards
compatibility needs to be preserved. Fortunately, by default Gson omits
writing null fields, so a field of type `List<T>?` could be replaced
with a field of type `List<T>` with a default value of `emptyList()` and
reading back the old data should still work. However, nullable lists
that are written directly (not as a field of another object) will still
be serialized to JSON as `"null"` so the deserializing code must still
be handling null properly.
Finally, changing the database schema is out of scope for this pull
request, so database entities that also happen to be serialized with
Gson will keep their original types even if they could be made non-null
as an improvement.
In the end this is all for the best, because the app will be more
reliable and errors will be easier to detect by showing up earlier with
a clear error message. Not to mention the performance benefits of using
Moshi compared to Gson.
- Replace Gson reflection with Moshi Kotlin codegen to generate all
parsers at compile time.
- Replace custom `Rfc3339DateJsonAdapter` with the one provided by
moshi-adapters.
- Replace custom `JsonDeserializer` classes for Enum types with
`EnumJsonAdapter.create(T).withUnknownFallback()` from moshi-adapters to
support fallback values.
- Replace `GuardedBooleanAdapter` with the more generic `GuardedAdapter`
which works with any type. Any nullable field may now be annotated with
`@Guarded`.
- Remove Proguard rules related to Json entities. Each Json entity needs
to be annotated with `@JsonClass` with no exception, and adding this
annotation will ensure that R8/Proguard will handle the entities
properly.
- Replace some nullable Boolean fields with non-null Boolean fields with
a default value where possible.
- Replace some nullable list fields with non-null list fields with a
default value of `emptyList()` where possible.
- Update `TimelineDao` to perform all Json conversions internally using
`Converters` so no Gson or Moshi instance has to be passed to its
methods.
- ~~Create a custom `DraftAttachmentJsonAdapter` to serialize and
deserialize `DraftAttachment` which is a special entity that supports
more than one json name per field. A custom adapter is necessary because
there is not direct equivalent of `@SerializedName(alternate = [...])`
in Moshi.~~ Remove alternate names for some `DraftAttachment` fields
which were used as a workaround to deserialize local data in 2-years old
builds of Tusky.
- Update tests to make them work with Moshi.
- Simplify a few `equals()` implementations.
- Change a few functions to `val`s
- Turn `NetworkModule` into an `object` (since it contains no abstract
methods).
Please test the app thoroughly before merging. There may be some fields
currently declared as mandatory that are actually optional.
Regression from #4291 // cc @cbeyls
<details>
<summary>Stacktrace</summary>
```
Process: com.keylesspalace.tusky, PID: 31230
java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.keylesspalace.tusky/com.keylesspalace.tusky.components.accountlist.AccountListActivity}:
java.lang.RuntimeException: java.lang.NoSuchMethodException: h4.a.values
[]
at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3635)
at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792)
at
android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)
at
android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at
android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7839)
at java.lang.reflect.Method.invoke(Native Method)
at
com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
Caused by: java.lang.RuntimeException: java.lang.NoSuchMethodException:
h4.a.values []
at java.lang.Enum.enumValues(Enum.java:270)
at java.lang.Enum.access$000(Enum.java:61)
at java.lang.Enum$1.create(Enum.java:277)
at java.lang.Enum$1.create(Enum.java:275)
at libcore.util.BasicLruCache.get(BasicLruCache.java:63)
at java.lang.Enum.getSharedConstants(Enum.java:289)
at java.lang.Enum.valueOf(Enum.java:243)
at java.io.ObjectInputStream.readEnum(ObjectInputStream.java:1841)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1409)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:427)
at android.os.Parcel.readSerializable(Parcel.java:3507)
at android.os.Parcel.readValue(Parcel.java:3277)
at android.os.Parcel.readArrayMapInternal(Parcel.java:3623)
at android.os.BaseBundle.initializeFromParcelLocked(BaseBundle.java:292)
at android.os.BaseBundle.unparcel(BaseBundle.java:236)
at android.os.BaseBundle.getSerializable(BaseBundle.java:1268)
at android.os.Bundle.getSerializable(Bundle.java:1104)
at android.content.Intent.getSerializableExtra(Intent.java:8575)
at
com.keylesspalace.tusky.components.accountlist.AccountListActivity.onCreate(SourceFile:23)
at android.app.Activity.performCreate(Activity.java:8051)
at android.app.Activity.performCreate(Activity.java:8031)
at
android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1329)
at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3608)
at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792)
at
android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)
at
android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at
android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7839)
at java.lang.reflect.Method.invoke(Native Method)
at
com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
Caused by: java.lang.NoSuchMethodException: h4.a.values []
at java.lang.Class.getMethod(Class.java:2103)
at java.lang.Class.getDeclaredMethod(Class.java:2081)
at java.lang.Enum.enumValues(Enum.java:267)
at java.lang.Enum.access$000(Enum.java:61)
at java.lang.Enum$1.create(Enum.java:277)
at java.lang.Enum$1.create(Enum.java:275)
at libcore.util.BasicLruCache.get(BasicLruCache.java:63)
at java.lang.Enum.getSharedConstants(Enum.java:289)
at java.lang.Enum.valueOf(Enum.java:243)
at java.io.ObjectInputStream.readEnum(ObjectInputStream.java:1841)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1409)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:427)
at android.os.Parcel.readSerializable(Parcel.java:3507)
at android.os.Parcel.readValue(Parcel.java:3277)
at android.os.Parcel.readArrayMapInternal(Parcel.java:3623)
at
android.os.BaseBundle.initializeFromParcelLocked(BaseBundle.java:292)
at android.os.BaseBundle.unparcel(BaseBundle.java:236)
at android.os.BaseBundle.getSerializable(BaseBundle.java:1268)
at android.os.Bundle.getSerializable(Bundle.java:1104)
at android.content.Intent.getSerializableExtra(Intent.java:8575)
at
com.keylesspalace.tusky.components.accountlist.AccountListActivity.onCreate(SourceFile:23)
at android.app.Activity.performCreate(Activity.java:8051)
at android.app.Activity.performCreate(Activity.java:8031)
at
android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1329)
at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3608)
at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3792)
at
android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:103)
at
android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at
android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2210)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7839)
at java.lang.reflect.Method.invoke(Native Method)
at
com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
```
</details>
closes#4297
Using saner defaults for R8 while reducing the app size even further.
- Add Kotlin compiler options to skip adding assertions in release
builds
- Remove `optimizations`, `optimizationpasses` and `dontpreverify` rules
that are ignored by R8
- Only keep runtime annotations by default. If other attributes are
needed by a specific library, these will already be provided by the
library rules (for example Retrofit or coroutines)
- Remove the obsolete rule allowing a View to reflectively call any
arbitrary public Activity method accepting a View as argument. This has
always been a bad practice and is not used in this project anyway
- Remove the rules related to enums. R8 already optimizes enums properly
out-of-the-box and keeping these rules may prevent some of these
optimizations
- Add support for the `@Keep` annotation. Even if it's not currently
used in the code base, it can be handy in the future
- Add a missing rule to prevent generic signature of `NetworkResult`
class from being removed in `MastodonApi` so Retrofit works
- Allow obfuscation and shrinking of `kotlin.coroutines.Continuation`,
matching the rule defined in the next release of Retrofit
- Remove the rule forcing the removal of `String.format()`. This method
is actually used in the code (and in third-party libraries) for other
things than logging so forcing its removal can do more harm than good.
This pull request removes the remaining RxJava code and replaces it with
coroutine-equivalent implementations.
- Remove all duplicate methods in `MastodonApi`:
- Methods returning a RxJava `Single` have been replaced by suspending
methods returning a `NetworkResult` in order to be consistent with the
new code.
- _sync_/_async_ method variants are replaced with the _async_ version
only (suspending method), and `runBlocking{}` is used to make the async
variant synchronous.
- Create a custom coroutine-based implementation of `Single` for usage
in Java code where launching a coroutine is not possible. This class can
be deleted after remaining Java code has been converted to Kotlin.
- `NotificationsFragment.java` can subscribe to `EventHub` events by
calling the new lifecycle-aware `EventHub.subscribe()` method. This
allows using the `SharedFlow` as single source of truth for all events.
- Rx Autodispose is replaced by `lifecycleScope.launch()` which will
automatically cancel the coroutine when the Fragment view/Activity is
destroyed.
- Background work is launched in the existing injectable
`externalScope`, since using `GlobalScope` is discouraged.
`externalScope` has been changed to be a `@Singleton` and to use the
main dispatcher by default.
- Transform `ShareShortcutHelper` to an injectable utility class so it
can use the application `Context` and `externalScope` as provided
dependencies to launch a background coroutine.
- Implement a custom Glide extension method
`RequestBuilder.submitAsync()` to do the same thing as
`RequestBuilder.submit().get()` in a non-blocking way. This way there is
no need to switch to a background dispatcher and block a background
thread, and cancellation is supported out-of-the-box.
- An utility method `Fragment.updateRelativeTimePeriodically()` has been
added to remove duplicate logic in `TimelineFragment` and
`NotificationsFragment`, and the logic is now implemented using a simple
coroutine instead of `Observable.interval()`. Note that the periodic
update now happens between onStart and onStop instead of between
onResume and onPause, since the Fragment is not interactive but is still
visible in the started state.
- Rewrite `BottomSheetActivityTest` using coroutines tests.
- Remove all RxJava library dependencies.
* Mark *PreferencesFragment as @Keep
PreferenceFragment references them by string name, which doesn't work after
ProGuard has obfuscated the code in release mode. The name is no longer
valid and the app crashes.
Fixes https://github.com/tuskyapp/Tusky/issues/3161
* Prefer to keep Preference classes with a Proguard rule
Ensures that all PreferenceFragmentCompat are kept, to prevent the risk
that this could break in a new fragment where `@Keep` is accidentally
omitted.
* update gradle, kotlin and other dependencies
* fix new warnings
* remove unused import
* update Proguard rules
* add explicit dependency on Gson to get the newest version
* remove debug flag from proguard rules again
* fix typo
* convert EmojiPreference and EmojiCompatFont to Kotlin
* move preference related to to dedicated preference package
* update proguard-rules.pro
* reformat & add comment
* maintain disposable information in EmojiPreference instead of EmojiCompatFont
* Replace Picasso library with Glide library tuskyapp#1082
* Replace Picasso library with Glide library tuskyapp#1082
* Update load emoji with glide
* Update context used for Glide
* Removed unused import
* Replace deprecated SimpleTarget with CustomTarget
* Fix crash at the view image fragment, remove override image size
* Replace Single.create with Single.fromCallable
* View image fragment refactor
* Fix after merge
* Try to load cached image first and show progress view on failure
* Try to load cached image first and show progress view on failure
Christophe Beyls
Zongle Wang
Konrad Pozniak
Nik Clayton
Frieder Bluemle
pandasoft0
Conny Duck
Ivan Kupalov
Vavassor
torrentcome