Fixed alpine based docker container creation script (#1963)

* Fixed alpine based docker container creation script

* Fixed build due to older flake8 issue

Author: pranavrth

examples/docker/Dockerfile.alpine

@@ -18,7 +18,7 @@
 # Alpine-based docker container with:
 #  * Python3
 #  * librdkafka (fully featured)
-#  * kafkacat (withouth schema-registry/Avro support)
+#  * kcat (withouth schema-registry/Avro support)
 #  * confluent-kafka-python
 #
 # How to build (from confluent-kafka-python top-level directory):
@@ -30,13 +30,14 @@ FROM alpine:3.12
 
 COPY . /usr/src/confluent-kafka-python
 
-ENV LIBRDKAFKA_VERSION v2.8.0
-ENV KAFKACAT_VERSION master
+ENV LIBRDKAFKA_VERSION="v2.8.0"
+ENV KCAT_VERSION="master"
+ENV CKP_VERSION="master"
 
 
-ENV BUILD_DEPS git make gcc g++ curl pkgconfig bsd-compat-headers zlib-dev openssl-dev cyrus-sasl-dev curl-dev zstd-dev yajl-dev python3-dev
+ENV BUILD_DEPS="git make gcc g++ curl pkgconfig bsd-compat-headers zlib-dev openssl-dev cyrus-sasl-dev curl-dev zstd-dev yajl-dev python3-dev"
 
-ENV RUN_DEPS bash libcurl cyrus-sasl-gssapiv2 ca-certificates libsasl heimdal-libs krb5 zstd-libs zstd-static yajl python3 py3-pip
+ENV RUN_DEPS="bash libcurl cyrus-sasl-gssapiv2 ca-certificates libsasl heimdal-libs krb5 zstd-libs zstd-static yajl python3 py3-pip"
 
 RUN \
     apk update && \
@@ -56,25 +57,25 @@ RUN \
     rm -rf /usr/src/librdkafka
 
 RUN \
-    echo Installing kafkacat && \
-    mkdir -p /usr/src/kafkacat && \
-    cd /usr/src/kafkacat && \
-    curl -LfsS https://github.com/edenhill/kafkacat/archive/${KAFKACAT_VERSION}.tar.gz | \
+    echo Installing kcat && \
+    mkdir -p /usr/src/kcat && \
+    cd /usr/src/kcat && \
+    curl -LfsS https://github.com/edenhill/kcat/archive/${KCAT_VERSION}.tar.gz | \
         tar xvzf - --strip-components=1 && \
     ./configure --prefix=/usr && \
     make -j && \
     make install && \
     cd / && \
-    rm -rf /usr/src/kafkacat && \
-    kafkacat -V
+    rm -rf /usr/src/kcat && \
+    kcat -V
 
 RUN \
     echo Installing confluent-kafka-python && \
     mkdir -p /usr/src/confluent-kafka-python && \
     cd /usr/src/confluent-kafka-python && \
     rm -rf build && \
     rm -rf dist && \
-    python3 -m pip install build \
+    python3 -m pip install build && \
     python3 -m build && \
     python3 -m pip install dist/confluent_kafka*whl && \
     cd / && \

tests/integration/integration_test.py

@@ -266,7 +266,6 @@ def __del__(self):
     # since there is a on_delivery reference to it.
     not_called_state = None
     gc.collect()
-    global DrOnlyTestSuccess_gced
     assert DrOnlyTestSuccess_gced == 0
 
     print('only.error: Waiting for flush of %d messages' % len(p))

tests/test_KafkaError.py

@@ -18,8 +18,6 @@ def error_cb(err):
 def test_error_cb():
     """ Test the error callback. """
 
-    global seen_all_brokers_down
-
     # Configure an invalid broker and make sure the ALL_BROKERS_DOWN
     # error is seen in the error callback.
     p = Producer({'bootstrap.servers': '127.0.0.1:1', 'socket.timeout.ms': 10,