Improve the reproducible build process.

* Moved stuff into it's own `reproducible-builds` directory.
* Improved reproducible build by using a debian snapshot and more clearly listing dependencies.
* Removed signing from assembleReelase.
* Updated README.

reproducible-builds/apkdiff/apkdiff.py

@@ -0,0 +1,79 @@
+#! /usr/bin/env python3
+
+import sys
+from zipfile import ZipFile
+
+class ApkDiff:
+    # resources.arsc is ignored due to https://issuetracker.google.com/issues/110237303
+    # May be fixed in Android Gradle Plugin 3.4
+    IGNORE_FILES = ["META-INF/MANIFEST.MF", "META-INF/SIGNAL_S.RSA", "META-INF/SIGNAL_S.SF", "resources.arsc"]
+
+    def compare(self, sourceApk, destinationApk):
+        sourceZip      = ZipFile(sourceApk, 'r')
+        destinationZip = ZipFile(destinationApk, 'r')
+
+        if self.compareManifests(sourceZip, destinationZip) and self.compareEntries(sourceZip, destinationZip) == True:
+            print("APKs match!")
+        else:
+            print("APKs don't match!")
+
+    def compareManifests(self, sourceZip, destinationZip):
+        sourceEntrySortedList      = sorted(sourceZip.namelist())
+        destinationEntrySortedList = sorted(destinationZip.namelist())
+
+        for ignoreFile in self.IGNORE_FILES:
+            while ignoreFile in sourceEntrySortedList: sourceEntrySortedList.remove(ignoreFile)
+            while ignoreFile in destinationEntrySortedList: destinationEntrySortedList.remove(ignoreFile)
+
+        if len(sourceEntrySortedList) != len(destinationEntrySortedList):
+            print("Manifest lengths differ!")
+
+        for (sourceEntryName, destinationEntryName) in zip(sourceEntrySortedList, destinationEntrySortedList):
+            if sourceEntryName != destinationEntryName:
+                print("Sorted manifests don't match, %s vs %s" % (sourceEntryName, destinationEntryName))
+                return False
+
+        return True
+
+    def compareEntries(self, sourceZip, destinationZip):
+        sourceInfoList      = list(filter(lambda sourceInfo: sourceInfo.filename not in self.IGNORE_FILES, sourceZip.infolist()))
+        destinationInfoList = list(filter(lambda destinationInfo: destinationInfo.filename not in self.IGNORE_FILES, destinationZip.infolist()))
+
+        if len(sourceInfoList) != len(destinationInfoList):
+            print("APK info lists of different length!")
+            return False
+
+        for sourceEntryInfo in sourceInfoList:
+            for destinationEntryInfo in list(destinationInfoList):
+                if sourceEntryInfo.filename == destinationEntryInfo.filename:
+                    sourceEntry      = sourceZip.open(sourceEntryInfo, 'r')
+                    destinationEntry = destinationZip.open(destinationEntryInfo, 'r')
+
+                    if self.compareFiles(sourceEntry, destinationEntry) != True:
+                        print("APK entry %s does not match %s!" % (sourceEntryInfo.filename, destinationEntryInfo.filename))
+                        return False
+
+                    destinationInfoList.remove(destinationEntryInfo)
+                    break
+
+        return True
+
+    def compareFiles(self, sourceFile, destinationFile):
+        sourceChunk      = sourceFile.read(1024)
+        destinationChunk = destinationFile.read(1024)
+
+        while sourceChunk != b"" or destinationChunk != b"":
+            if sourceChunk != destinationChunk:
+                return False
+
+            sourceChunk      = sourceFile.read(1024)
+            destinationChunk = destinationFile.read(1024)
+
+        return True
+
+if __name__ == '__main__':
+    if len(sys.argv) != 3:
+        print("Usage: apkdiff <pathToFirstApk> <pathToSecondApk>")
+        sys.exit(1)
+
+    ApkDiff().compare(sys.argv[1], sys.argv[2])