Feat: add prebuilt openssl binaries

Dockerfile

@@ -6,6 +6,7 @@ ARG QT_VERSION="5.15.5"
 ARG ANDROID_PLATFORM_VERSION="android-29"
 ARG ANDROID_BUILDTOOLS_VERSION="29.0.2"
 ARG ANDROID_NDK_VERSION="21.3.6528147"
+ARG OPENSSL_VERSION="1.1.1l_1.0.2u"
 
 WORKDIR /workspace
 
@@ -57,7 +58,13 @@ RUN echo "**** setup environment ****" && \
     rm -rf workspace && \
     echo "**** done ****"
 
+RUN echo "**** download openssl binaries ****" && \
+    wget https://github.com/KDAB/android_openssl/archive/refs/tags/${OPENSSL_VERSION}.tar.gz -o android_openssl.tar.gz && \
+    tar -xf android_openssl.tar.xz --strip-components=1 -C /usr/lib/android-sdk/android_openssl && \
+    rm android_openssl.tar.gz
+
 ENV PATH="${PATH}:/usr/lib/qt/bin:/usr/lib/jvm/java-8-openjdk-amd64/bin"
+ENV ANDROID_HOME=/usr/lib/android-sdk
 WORKDIR /src
 
 COPY "qt-build" "/usr/local/bin/qt-build"

README.md

@@ -48,3 +48,13 @@ docker run --rm -e PLUGIN_FOLDER=public -e PLUGIN_SSH_KEY=foo \
   -v $(pwd):/drone/src \
   itsblue.dev/plugins/qt-android
 ```
+
+# Using openssl
+
+This image includes [prebuilt openssl libraries](https://github.com/KDAB/android_openssl). You may include them in your .pro file like so:
+```pro
+android {
+    ANDROID_HOME = $$(ANDROID_HOME)
+    include($$ANDROID_HOME/android_openssl/openssl.pri)
+}
+```