Issue with buildozer packaging a kivy app

Question

I'm trying to package my kivy app and I'm having problems with buildozer. Some weeks ago it worked in a right way but today I got this error:

Traceback (most recent call last):
  File "build.py", line 517, in <module>
    make_package(args)
  File "build.py", line 365, in make_package
    subprocess.check_call([ANT, arg])
  File "/usr/lib/python2.7/subprocess.py", line 540, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['ant', 'debug']' returned non-zero exit status 1

I've been reading about this error ( https://github.com/kivy/buildozer/issues/205 ) and maybe the problem is with the version of the sdk and ndk. Here I attach my buildozer.spec file because maybe I'm doing something in a wrong way.

[app]

# (str) Title of your application
title = Etseib Calendar
# (str) Package name
package.name = etseibcalendar

# (str) Package domain (needed for android/ios packaging)
package.domain = org.test

# (str) Source code where the main.py live
source.dir = .

# (list) Source files to include (let empty to include all the files)
source.include_exts = py,png,jpg,kv,atlas

# (list) List of inclusions using pattern matching
#source.include_patterns = assets/*,images/*.png

# (list) Source files to exclude (let empty to not exclude anything)
#source.exclude_exts = spec

# (list) List of directory to exclude (let empty to not exclude anything)
#source.exclude_dirs = tests, bin

# (list) List of exclusions using pattern matching
#source.exclude_patterns = license,images/*/*.jpg

# (str) Application versioning (method 1)
version = 0.1

# (str) Application versioning (method 2)
# version.regex = __version__ = ['"](.*)['"]
# version.filename = %(source.dir)s/main.py

# (list) Application requirements
# comma seperated e.g. requirements = sqlite3,kivy
requirements = kivy,sqlite3,requests,simplejson,icalendar,datetime,pytz,HTMLParser,email,openssl

# (str) Custom source folders for requirements
# Sets custom source for any requirements with recipes
# requirements.source.kivy = ../../kivy

# (list) Garden requirements
#garden_requirements =

# (str) Presplash of the application
presplash.filename = hdd33.png

# (str) Icon of the application
icon.filename = icon.png

# (str) Supported orientation (one of landscape, portrait or all)
orientation = landscape

# (list) List of service to declare
#services = NAME:ENTRYPOINT_TO_PY,NAME2:ENTRYPOINT2_TO_PY

#
# OSX Specific
#

#
# author = © Copyright Info

#
# Android specific
#

# (bool) Indicate if the application should be fullscreen or not
fullscreen = 1

# (list) Permissions
android.permissions = INTERNET

# (int) Android API to use
#android.api = 19

# (int) Minimum API required
#android.minapi = 9

# (int) Android SDK version to use
#android.sdk = 20

# (str) Android NDK version to use
#android.ndk = 9c

# (bool) Use --private data storage (True) or --dir public storage (False)
#android.private_storage = True

# (str) Android NDK directory (if empty, it will be automatically downloaded.)
#android.ndk_path =

# (str) Android SDK directory (if empty, it will be automatically downloaded.)
#android.sdk_path =

# (str) ANT directory (if empty, it will be automatically downloaded.)
#android.ant_path =

# (str) python-for-android git clone directory (if empty, it will be automatically cloned from github)
#android.p4a_dir =

# (list) python-for-android whitelist
#android.p4a_whitelist =

# (bool) If True, then skip trying to update the Android sdk
# This can be useful to avoid excess Internet downloads or save time
# when an update is due and you just want to test/build your package
# android.skip_update = False

# (str) Bootstrap to use for android builds (android_new only)
# android.bootstrap = sdl2

# (str) Android entry point, default is ok for Kivy-based app
#android.entrypoint = org.renpy.android.PythonActivity

# (list) List of Java .jar files to add to the libs so that pyjnius can access
# their classes. Don't add jars that you do not need, since extra jars can slow
# down the build process. Allows wildcards matching, for example:
# OUYA-ODK/libs/*.jar
#android.add_jars = foo.jar,bar.jar,path/to/more/*.jar

# (list) List of Java files to add to the android project (can be java or a
# directory containing the files)
#android.add_src =

# (str) python-for-android branch to use, if not master, useful to try
# not yet merged features.
#android.branch = master

# (str) OUYA Console category. Should be one of GAME or APP
# If you leave this blank, OUYA support will not be enabled
#android.ouya.category = GAME

# (str) Filename of OUYA Console icon. It must be a 732x412 png image.
#android.ouya.icon.filename = %(source.dir)s/data/ouya_icon.png

# (str) XML file to include as an intent filters in <activity> tag
#android.manifest.intent_filters =

# (list) Android additionnal libraries to copy into libs/armeabi
#android.add_libs_armeabi = libs/android/*.so
#android.add_libs_armeabi_v7a = libs/android-v7/*.so
#android.add_libs_x86 = libs/android-x86/*.so
#android.add_libs_mips = libs/android-mips/*.so

# (bool) Indicate whether the screen should stay on
# Don't forget to add the WAKE_LOCK permission if you set this to True
#android.wakelock = False

# (list) Android application meta-data to set (key=value format)
#android.meta_data =

# (list) Android library project to add (will be added in the
# project.properties automatically.)
#android.library_references =

# (str) Android logcat filters to use
#android.logcat_filters = *:S python:D

# (bool) Copy library instead of making a libpymodules.so
#android.copy_libs = 1

#
# iOS specific
#

# (str) Path to a custom kivy-ios folder
#ios.kivy_ios_dir = ../kivy-ios

# (str) Name of the certificate to use for signing the debug version
# Get a list of available identities: buildozer ios list_identities
#ios.codesign.debug = "iPhone Developer: <lastname> <firstname> (<hexstring>)"

# (str) Name of the certificate to use for signing the release version
#ios.codesign.release = %(ios.codesign.debug)s


[buildozer]

# (int) Log level (0 = error only, 1 = info, 2 = debug (with command output))
log_level = 2

# (int) Display warning if buildozer is run as root (0 = False, 1 = True)
warn_on_root = 1

# (str) Path to build artifact storage, absolute or relative to spec file
# build_dir = ./.buildozer

# (str) Path to build output (i.e. .apk, .ipa) storage
# bin_dir = ./bin

#    -----------------------------------------------------------------------------
#    List as sections
#
#    You can define all the "list" as [section:key].
#    Each line will be considered as a option to the list.
#    Let's take [app] / source.exclude_patterns.
#    Instead of doing:
#
#[app]
#source.exclude_patterns = license,data/audio/*.wav,data/images/original/*
#
#    This can be translated into:
#
#[app:source.exclude_patterns]
#license
#data/audio/*.wav
#data/images/original/*
#


#    -----------------------------------------------------------------------------
#    Profiles
#
#    You can extend section / key with a profile
#    For example, you want to deploy a demo version of your application without
#    HD content. You could first change the title to add "(demo)" in the name
#    and extend the excluded directories to remove the HD content.
#
#[app@demo]
#title = My Application (demo)
#
#[app:source.exclude_patterns@demo]
#images/hd/*
#
#    Then, invoke the command line with the "demo" profile:
#
#buildozer --profile demo android debug

As I have said at the begining of the post, a few weeks ago it worked properly and I don't know why now this is happening to me. Just in case the full log of buildozer is needed, I attach here the last lines of the output using buildozer --verbose android debug :

BUILD FAILED
/home/alejandro/.buildozer/android/platform/android-sdk-20/tools/ant/build.xml:888: The following error occurred while executing this line:
/home/alejandro/.buildozer/android/platform/android-sdk-20/tools/ant/build.xml:890: The following error occurred while executing this line:
/home/alejandro/.buildozer/android/platform/android-sdk-20/tools/ant/build.xml:902: The following error occurred while executing this line:
/home/alejandro/.buildozer/android/platform/android-sdk-20/tools/ant/build.xml:283: null returned: 1

Total time: 2 seconds
e.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/WHEEL
assets/private.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/top_level.txt
assets/private.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/metadata.json
assets/private.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/RECORD
assets/private.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/DESCRIPTION.rst
assets/private.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/METADATA
assets/private.mp3: /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app/_applibs/DateTime-4.1.1.dist-info/INSTALLER
Traceback (most recent call last):
  File "build.py", line 517, in <module>
    make_package(args)
  File "build.py", line 365, in make_package
    subprocess.check_call([ANT, arg])
  File "/usr/lib/python2.7/subprocess.py", line 540, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['ant', 'debug']' returned non-zero exit status 1
# Command failed: python build.py --name 'Etseib Calendar' --version 0.1 --package org.test.etseibcalendar --sdk 19 --minsdk 9 --private /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/.buildozer/android/app --permission INTERNET --presplash /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/hdd33.png --icon /home/alejandro/ABRIL/Presentacion/APK/APK-25.06/icon.png --orientation landscape debug
# 
# Buildozer failed to execute the last command
# The error might be hidden in the log above this error
# Please read the full log, and search for it before
# raising an issue with buildozer itself.
# In case of a bug report, please add a full log with log_level = 2

Answer 1

Well, after looking for the answer in some forums I have achieved the correct way to fix the issue. In the buildozer.spec file I changed the sdk version to the last version avaible:

# (int) Android SDK version to use android.sdk = 24

After that I executed buildozer and tried to download the version I've specified in the .spec file, and this time the creation of the apk file was well done.