The Android Story: Quality, Performance, Stability. ENG (MBLTdev 2017, Moscow)

Overview of tools aimed at increasing the quality of the applications. Static code analysis tools, dev tools, application metrics and environment helpers.

Transcript

1. The Android Story: Quality, Performance, Stability. Oleksandr Tolstykh, Head of Mobile @ Sharewire BV
2. Quality tools Lint, infer, checkstyle, copy-paste detector...
3. Lint Out of the box Android Studio integration Custom rules Lint baseline! Android specific 200 different checks Fully configurable https://www.bignerdranch.com/blog/building-custom-lint-checks-in-android/
4. android { // ... lintOptions { warningsAsErrors false abortOnError true // github.com/square/okio/issues/58 disable 'InvalidPackage' // App isn't indexable by Google Search disable 'GoogleAppIndexingWarning' // ... } } android { // ... lintOptions { abortOnError false } } Bad! http://tools.android.com/tips/lint-checks The right way!
5. Lint, check examples MissingSuperCall & other support annotations CommitTransaction ResourceType (@StringRes, @DrawableRes, @ColorRes) NewApi http://tools.android.com/tips/lint-checks … and many others
6. Lint in action Android Studio integration
7. BUT, I have a legacy project... Lint baseline! https://developer.android.com/studio/write/lint.html#snapshot Skip existing issues Check only new ones! Baseline warning
8. http://tools.android.com/tech-docs/lint-in-studio-2-3#TOC-Creating-a-Baseline android { lintOptions { baseline file("lint-baseline.xml") // your choice of filename/path here } } $ ./gradlew lintDebug ......... Wrote XML report to file:///lint-results-debug.xml Lint found 4 warnings :base:lintDebug
9. http://tools.android.com/tech-docs/lint-in-studio-2-3#TOC-Creating-a-Baseline android { lintOptions { baseline file("lint-baseline.xml") // your choice of filename/path here } } $ ./gradlew lintDebug ......... Wrote XML report to file:///lint-results-debug.xml Lint found 1 warning (3 warnings filtered by baseline lint-baseline.xml) :base:lintDebug
10. Infer Advanced analysis - inter-procedural Command line or plugin Easy to install Java, ObjectiveC, C/C++ http://fbinfer.com/
12. Infer $ brew install infer http://fbinfer.com/docs/analyzing-apps-or-projects.html $ ./gradlew clean $ infer run -- ./gradlew assembleDebug ... RESOURCE_LEAK: 17 NULL_DEREFERENCE: 5 CONTEXT_LEAK: 1
13. proj/src/main/java/some/package/FileManager.java:77: error: NULL_DEREFERENCE object returned by `dir.files()` could be null and is dereferenced at line 9 7. private void clearStorageSpace(Dir dir, long requiredSpace) { 8. long spaceCleared = 0; 9. > for (File file : dir.files()) { 10. long fileLength = file.length(); 11. http://fbinfer.com/docs/analyzing-apps-or-projects.html
14. findbugs Java bytecode analysis https://docs.gradle.org/current/dsl/org.gradle.api.plugins.quality.FindBugs.html http://findbugs.sourceforge.net/ Android Studio plugin Requires some effort to configure initially
15. plugins.apply('findbugs') task findbugs(type: FindBugs) { ignoreFailures = false effort = 'max' reportLevel = 'high' // Report only high priority problems. classes = files("${project.projectDir}/build/intermediates/classes") source = fileTree('src/main/java') classpath = files() reports { xml.enabled = true html.enabled = false } excludeFilter = rootProject.file('quality/findbugs.xml') }
16. String result = ""; for (String field : fields) { result += field + " "; }
17. String result = ""; for (String field : fields) { result += field + " "; // <-- issue USE_STRINGBUFFER_CONCATENATION }
18. String result = ""; for (String field : fields) { result += field + " "; // <-- issue USE_STRINGBUFFER_CONCATENATION } StringBuilder resultBuilder = new StringBuilder(); for (String field : fields) { resultBuilder.append(field).append(" "); }
19. findbugs Bug description examples http://findbugs.sourceforge.net/bugDescriptions.html Comparison of String objects using == or != Method invokes toString() method on a String Test for floating point equality Method may fail to close stream Unread fields/methods … and many others
20. PMD Java source code analysis https://pmd.github.io/ https://docs.gradle.org/current/userguide/pmd_plugin.html Similar to findbugs Requires some effort to configure initially
21. plugins.apply('pmd') pmd { toolVersion = '5.5.3' } task pmd(type: Pmd) { ignoreFailures = false rulePriority = 2 source = fileTree('src/main/java') ruleSetFiles = rootProject.files('quality/pmd.xml') } http://pmd.sourceforge.net/pmd-4.3.0/howtomakearuleset.html
22. PMD GodClass DoNotHardCodeSDCard. Use getExternalStorageDirectory() instead of “/sdcard” AvoidInstantiatingObjectsInLoops AvoidCatchingThrowable, AvoidCatchingNPE UncommentedEmptyMethodBody, UncommentedEmptyConstructor … and many others https://pmd.github.io/pmd-5.4.1/pmd-java/rules/index.html
23. checkstyle https://github.com/checkstyle/checkstyle Class & method design problems Code layout issues Formatting issues
24. plugins.apply('checkstyle') task checkstyle(type: Checkstyle) { ignoreFailures = false showViolations = true source = 'src' include '**/*.java' classpath = files() configFile rootProject.file('quality/checkstyle.xml') }
25. <module name="Checker"> <module name="FileTabCharacter"/> <!-- checks for tabs --> <module name="TreeWalker"> <!-- main check group --> <module name="ConstantName" /> <module name="LocalVariableName" /> <module name="AvoidStarImport" /> <module name="UnusedImports" /> <module name="LineLength"> <property name="max" value="100"/> </module> <module name="MethodLength" /> <!-- many other checks --> </module> <module name="SuppressionCommentFilter"/> <!-- allows exceptions --> </module> http://checkstyle.sourceforge.net/checks.html
26. COPY-PASTE DETECTOR https://pmd.github.io/pmd-5.4.1/usage/cpd-usage.html https://github.com/aaschmid/gradle-cpd-plugin Ignore imports and copyrights Integrated or stand-alone tool (.bat/.sh) cpp, java, objective-c, php, python, ruby, scala...
27. plugins.apply('cpd') cpdCheck { reports { text.enabled = true xml.enabled = false } minimumTokenCount = 100 source = fileTree('src/main/java') } https://github.com/aaschmid/gradle-cpd-plugin
28. https://pmd.github.io/pmd-5.4.1/usage/cpd-usage.html $ ./gradlew cpdCheck * What went wrong: Execution failed for task ':app:cpdCheck'. > CPD found duplicate code. See the report at file:///some/path/cpdCheck.text BUILD FAILED in 4s
29. Strict mode https://developer.android.com/reference/android/os/StrictMode.html Issues detection during development Out of the box Debug only! Flexibility in penalties
30. public void setupStrictMode() { if (DEVELOPER_MODE) { // if (BuildConfig.DEBUG) StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder() .detectDiskReads() .detectDiskWrites() .detectNetwork() // .detectAll() for all detectable problems .penaltyLog() .build()); StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder() .detectLeakedSqlLiteObjects() .detectLeakedClosableObjects() .penaltyLog() .penaltyDeath() .build()); } }
31. So many... Which one should I use?
32. Copy-paste detector -> more than one dev? Than yes! Infer -> try it PMD / findbug -> quality obsessed! Lint -> Always! StrictMode -> preferable! Checkstyle -> more than one dev? Than yes! Kotliners? Detekt -> https://github.com/arturbosch/detekt not enough? -> check SonarQube, SonarJava, ............
33. CI integration RECIPE: - Use pull requests - Run checks on every pull-request - Commit status publisher!
34. All tools + All checks = "Nigthmare"
35. Warning || Error != BUG
36. What is the outcome? https://developer.android.com/studio/write/lint.html#snapshot Extra effort for the first time. Run all quality checks ONLY before making a commit. Quality tools + CI = MAXIMUM PROFIT! Your team should be ready for it. Better app quality, performance, readability.
37. Dev tools Stetho, LeakCanary, Lynx, Timber ...
38. Developer tools Debug only Stand-alone Scalable Useful Should be:
39. Stetho Network Inspection Shared preferences viewer View Hierarchy Database Inspection http://facebook.github.io/stetho/ Debug bridge in the Browser. Developed by Facebook.
40. http://facebook.github.io/stetho/ public class MyApplication extends Application { public void onCreate() { super.onCreate(); Stetho.initializeWithDefaults(this); } } // OkHttp initialization new OkHttpClient.Builder() .addNetworkInterceptor(new StethoInterceptor()) .build();
41. CHUCK An in-app HTTP inspector for Android OkHttp clients https://github.com/jgilfelt/chuck OkHttpClient client = new OkHttpClient.Builder() .addInterceptor(new ChuckInterceptor(context)) .build();
42. LeakCanary A memory leak detection library for Android and Java. https://github.com/square/leakcanary public class MyApplication extends Application { public void onCreate() { super.onCreate(); LeakCanary.install(this); } }
43. Lynx An in-app logcat access https://github.com/pedrovgs/Lynx Text filtering Filtering by log level Logs sharing Appears by shaking
44. Timber by Jake Wharton “Every time you log in production, a puppy dies.” – Jake Wharton https://github.com/JakeWharton/timber Simple log configuration Shipped with embedded lint rules
45. private void initTimber() { if (BuildConfig.DEBUG) { Timber.plant(new Timber.DebugTree()); } else { Timber.plant(new CrashlyticsTree()); } } Timber.i("Log your message"); // support formatting Timber.i("Hello, %s %s", firstName, lastName);
46. Logger https://github.com/orhanobut/logger Extensive & pretty logging. Timber integration. Timber.plant(new Timber.DebugTree() { void log(int priority, String tag, String message, Throwable t) { Logger.log(priority, tag, message, t); } });
47. https://github.com/orhanobut/logger E/PRETTY_LOGGER: ┌───────────────────────────── E/PRETTY_LOGGER: │ Thread: main E/PRETTY_LOGGER: ├┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄ E/PRETTY_LOGGER: │ Activity.performCreate (Activity.java:6289) E/PRETTY_LOGGER: │ MapActivity.onCreate (MapActivity.java:183) E/PRETTY_LOGGER: ├┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄ E/PRETTY_LOGGER: │ some error message E/PRETTY_LOGGER: └───────────────────────────── I/PRETTY_LOGGER: ┌───────────────────────────── I/PRETTY_LOGGER: │ just some info message I/PRETTY_LOGGER: └───────────────────────────── D/PRETTY_LOGGER: ┌───────────────────────────── D/PRETTY_LOGGER: │ { D/PRETTY_LOGGER: │ "id": "1278", D/PRETTY_LOGGER: │ "name": "John" D/PRETTY_LOGGER: │ } D/PRETTY_LOGGER: └─────────────────────────────
48. Only in release versions Log error/unexpected states Descriptive error messages Enable on early stages Crash-reporting tool
49. Extract tools into a separate library, if you have too many. Your developer settings should be easily maintainable. Add as many dev tools as your project needs. Summary
50. Application metrics Tiny Dancer, Hugo, AndroidDevMetrics ...
51. Build time Launch time Application size Test coverage (JaCoCo) General metrics Always keep track of: https://docs.gradle.org/current/userguide/jacoco_plugin.html
52. Tiny Dancer A real time frames per second measuring library for Android https://github.com/friendlyrobotnyc/TinyDancer Fps of your current window
53. Hugo Annotation-triggered method call logging for your debug builds. https://github.com/JakeWharton/hugo Logs arguments and return values for method Logs execution time
54. Hugo Annotation-triggered method call logging for your debug builds. https://github.com/JakeWharton/hugo @DebugLog public String getName(String first, String last) { SystemClock.sleep(15); // Don't ever really do this! return first + " " + last; } V/Example: ⇢ getName(first="Jake", last="Wharton") V/Example: ⇠ getName [16ms] = "Jake Wharton"
55. ANDROID DEV METRICS Performance metrics library for Android development. https://github.com/frogermcs/AndroidDevMetrics Measures activity lifecycle callbacks Measures Dagger 2 object initializations Schedule method tracing Counts fps drops
56. Environment tools. Helpers
57. JSON to POJO http://www.jsonschema2pojo.org/ { "userId": 12345, "email": "some@email.com", "vehicles": [ { "vehicleId": "54321", "plate": "1ABC23" } ], "paymentDetails":null } public class Example { @SerializedName("userId") @Expose private int userId; @SerializedName("email") @Expose private String email; @SerializedName("vehicles") @Expose private List<Vehicle> vehicles = null; @SerializedName("paymentDetails") @Expose private Object paymentDetails; }
58. Single storage for all platforms Operate with ids, not values Automate strings import (if possible) Work with generated files Resources management Strings (translations) or colors management https://crowdin.com/ https://localise.biz/
59. Difficulties with color naming? Name that Color! http://chir.ag/projects/name-that-color #DCD6D5 #FEE56D Kournikova Swiss Coffee
60. Add only tools you will really need. AFFECTS BUILD TIME! No warnings != no bugs. All given above tools are designed to help, but not annoy you. Wrap up Be patient! It may take longer for the first time...
61. Thanks! @a_tolstykh @a_tolstykh @a-tolstykh