Add instructions for building the app & for reproducible builds of apk in google-play

[emanuelb]

Using ContainerFile:
compile: podman build --pull --rm -t xwallet_build_apk -f ContainerFile

FROM frolvlad/alpine-glibc

RUN set -ex; \
    apk update; \
    apk add --no-cache \
        openjdk8 \
        bash \
        git; \
    adduser -D appuser;

USER appuser

ENV ANDROID_SDK_ROOT="/home/appuser/app/sdk" \
    ANDROID_HOME="/home/appuser/app/sdk"
    
RUN set -ex; \
    mkdir -p "/home/appuser/app/sdk/licenses" "/home/appuser/app/xwallet/"; \
    printf "\n24333f8a63b6825ea9c5514f83c2829b004d1fee" > "/home/appuser/app/sdk/licenses/android-sdk-license"; \
    cd /home/appuser/app/xwallet/; \
    git clone https://github.com/ehanoc/xwallet/; \
    cd xwallet;
     
WORKDIR /home/appuser/app/xwallet/xwallet/

then run: run: podman run --rm --name xwallet_built_apk -ti xwallet_build_apk

inside container:

Running ./gradle assembleRelease Result:

* What went wrong:
A problem occurred configuring root project 'xwallet'.
> Could not resolve all dependencies for configuration ':classpath'.
   > Could not find com.getkeepsafe.dexcount:dexcount-gradle-plugin:0.6.3-SNAPSHOT.
     Searched in the following locations:
         https://jcenter.bintray.com/com/getkeepsafe/dexcount/dexcount-gradle-plugin/0.6.3-SNAPSHOT/maven-metadata.xml
         https://jcenter.bintray.com/com/getkeepsafe/dexcount/dexcount-gradle-plugin/0.6.3-SNAPSHOT/dexcount-gradle-plugin-0.6.3-SNAPSHOT.pom
         https://jcenter.bintray.com/com/getkeepsafe/dexcount/dexcount-gradle-plugin/0.6.3-SNAPSHOT/dexcount-gradle-plugin-0.6.3-SNAPSHOT.jar
         https://oss.sonatype.org/content/repositories/snapshots/com/getkeepsafe/dexcount/dexcount-gradle-plugin/0.6.3-SNAPSHOT/maven-metadata.xml
         https://oss.sonatype.org/content/repositories/snapshots/com/getkeepsafe/dexcount/dexcount-gradle-plugin/0.6.3-SNAPSHOT/dexcount-gradle-plugin-0.6.3-SNAPSHOT.pom
         https://oss.sonatype.org/content/repositories/snapshots/com/getkeepsafe/dexcount/dexcount-gradle-plugin/0.6.3-SNAPSHOT/dexcount-gradle-plugin-0.6.3-SNAPSHOT.jar
     Required by:
         project :

Fix by running: sed -i 's/0.6.3-SNAPSHOT/0.6.3/' build.gradle
as no version 0.6.3-SNAPSHOT exists: https://mvnrepository.com/artifact/com.getkeepsafe.dexcount/dexcount-gradle-plugin

Then errors:

:app:compileReleaseJavaWithJavac
:app:compileReleaseJavaWithJavac - is not incremental (e.g. outputs have changed, no previous execution, etc.).
/home/appuser/app/xwallet/xwallet/app/src/main/java/com/bytetobyte/xwallet/ui/activity/MainActivity.java:70: error: cannot find symbol
        new TwitterAuthApi(getString(R.string.twitter_api_key), getString(R.string.twitter_api_secret), this).execute();
                                             ^
  symbol:   variable twitter_api_key
  location: class string
/home/appuser/app/xwallet/xwallet/app/src/main/java/com/bytetobyte/xwallet/ui/activity/MainActivity.java:70: error: cannot find symbol
        new TwitterAuthApi(getString(R.string.twitter_api_key), getString(R.string.twitter_api_secret), this).execute();
                                                                                  ^
  symbol:   variable twitter_api_secret
  location: class string
/home/appuser/app/xwallet/xwallet/app/src/main/java/com/bytetobyte/xwallet/util/EncryptUtils.java:20: error: cannot find symbol
        String key = context.getString(R.string.skey);
                                               ^
  symbol:   variable skey
  location: class string
/home/appuser/app/xwallet/xwallet/app/src/main/java/com/bytetobyte/xwallet/util/EncryptUtils.java:21: error: cannot find symbol
        String salt = context.getString(R.string.ksalt);
                                                ^
  symbol:   variable ksalt
  location: class string
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
4 errors
:app:compileReleaseJavaWithJavac FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:compileReleaseJavaWithJavac'.
> Compilation failed; see the compiler error output for details.

fix by adding below to file ./app/src/main/res/values/strings.xml under wallet_str at:
https://github.com/ehanoc/xwallet/blob/6a49d1a82f5bbb55103a33b85b393700d78fa817/app/src/main/res/values/strings.xml#L5

values taken from APK downloaded from google-play version: 0.3.1-beta.

    <string name="twitter_api_key">ReDJqIMcBqYqGrAGbWvOfXgAi</string>
    <string name="twitter_api_secret">U6JUq7TfkIa1JgKZ73EnTeSIbCmxRofg94QiaylGcZXCyaAL2l</string>
    <string name="skey">as@_a%sdzzWas=</string>
    <string name="ksalt">uTwbhys%ahakw</string>
    <string name="fkey">30251af42f431aaef6163744c97d7a8b9ba59fe0</string>
    <string name="com_crashlytics_android_build_id">0b697bad-85c1-40e6-9c22-9a1b85b0fe9c</string>

Then app compiled, APK in: /home/appuser/app/xwallet/xwallet/app/build/outputs/apk/app-release-unsigned.apk
But there difference between the results & the apk downloaded from google-play, see related issue to publish code for 0.3.1-beta version, see issue #2 (as the compiled version is 0.3.0-beta)

diffs are:

Files ./FromGoogle/AndroidManifest.xml and ./LocalBuild/AndroidManifest.xml differ
Only in ./FromGoogle/assets: crashlytics-build.properties
Files ./FromGoogle/classes2.dex and ./LocalBuild/classes2.dex differ
Files ./FromGoogle/classes.dex and ./LocalBuild/classes.dex differ
Only in ./FromGoogle: fabric
Only in ./FromGoogle/META-INF: CERT.RSA
Only in ./FromGoogle/META-INF: CERT.SF
Files ./FromGoogle/META-INF/MANIFEST.MF and ./LocalBuild/META-INF/MANIFEST.MF differ
Files ./FromGoogle/res/layout/fragment_wallet_backup.xml and ./LocalBuild/res/layout/fragment_wallet_backup.xml differ
Files ./FromGoogle/resources.arsc and ./LocalBuild/resources.arsc differ