Merge branch 'master' into backend

.bumpversion.cfg

@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 4.3.0
+current_version = 4.4.0rc4
 commit = True
 tag = True
 parse = (?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)(?P<releaselevel>[a-z\d]+)?

.github/ISSUE_TEMPLATE/Minor-Version-Release-Checklist.md

@@ -0,0 +1,21 @@
+---
+name: Minor Version Release Checklist
+about: About to release a new minor version? (Maintainers Only!)
+---
+
+Version: <!-- Insert Version Here -->
+Release PR: <!-- Insert Release PR Here -->
+
+# Checklist
+
+- [ ] Release PR drafted
+- [ ] Release PR reviewed
+- [ ] The master branch build passes
+
+    [![Build Status](https://travis-ci.org/celery/celery.svg?branch=master)](https://travis-ci.org/celery/celery)
+- [ ] Release Notes
+- [ ] What's New
+
+# Release Blockers
+
+# Potential Release Blockers

.gitignore

@@ -30,3 +30,4 @@ cover/
 htmlcov/
 coverage.xml
 test.db
+pip-wheel-metadata/

.travis.yml

@@ -1,12 +1,12 @@
 language: python
-sudo: required
-dist: xenial
+dist: bionic
 cache: pip
 python:
   - '2.7'
   - '3.5'
   - '3.6'
   - '3.7'
+  - '3.8'
 os:
     - linux
 stages:
@@ -20,56 +20,62 @@ env:
   - MATRIX_TOXENV=unit
 
 matrix:
+  fast_finish: true
   include:
-  - python: 3.7
+  - python: 3.8
     env: MATRIX_TOXENV=integration-rabbitmq
     stage: integration
 
-  - python: 3.7
+  - python: 3.8
     env: MATRIX_TOXENV=integration-redis
     stage: integration
 
-  - python: 3.7
+  - python: 3.8
     env: MATRIX_TOXENV=integration-dynamodb
     stage: integration
 
-  - python: 3.7
+  - python: 3.8
     env: MATRIX_TOXENV=integration-azureblockblob
     stage: integration
 
-  - python: '3.7'
+  - python: 3.8
+    env: MATRIX_TOXENV=integration-cache
+    stage: integration
+
+  - python: '3.8'
     env: TOXENV=flake8
     stage: lint
-  - python: '3.7'
+  - python: '3.8'
     env: TOXENV=apicheck
     stage: lint
-  - python: '3.7'
+  - python: '3.8'
     env: TOXENV=configcheck
     stage: lint
-  - python: '3.7'
+  - python: '3.8'
     env: TOXENV=bandit
     stage: lint
-  - python: '3.7'
+  - python: '3.8'
     env: TOXENV=pydocstyle
     stage: lint
   - python: '2.7'
     env: TOXENV=flakeplus
     stage: lint
-  - python: pypy2.7-7.1.1
+  - python: pypy2.7-7.2
     env: TOXENV=pypy
-    dist: xenial
     before_install: sudo apt-get update && sudo apt-get install libgnutls-dev
   - python: pypy3.5-7.0
     env: TOXENV=pypy3
-    dist: xenial
+    before_install: sudo apt-get update && sudo apt-get install libgnutls-dev
+  - python: pypy3.6-7.2
+    env: TOXENV=pypy3
     before_install: sudo apt-get update && sudo apt-get install libgnutls-dev
 
 before_install:
     - sudo apt install libcurl4-openssl-dev libssl-dev gnutls-dev
     - if [[ -v MATRIX_TOXENV ]]; then export TOXENV=${TRAVIS_PYTHON_VERSION}-${MATRIX_TOXENV}; fi; env
     - |
           if [[ "$TOXENV" == *integration* ]]; then
-              sudo echo 'deb https://dl.bintray.com/rabbitmq-erlang/debian xenial main' > /etc/apt/sources.list.d/rabbitmq-bintray.list
+              sudo echo 'deb https://dl.bintray.com/rabbitmq-erlang/debian bionic main' > /etc/apt/sources.list.d/rabbitmq-bintray.list
               sudo apt-key adv --keyserver "hkps.pool.sks-keyservers.net" --recv-keys "0x6B73A36E6026DFCA"
               wget -O - "https://github.com/rabbitmq/signing-keys/releases/download/2.0/rabbitmq-release-signing-key.asc" | sudo apt-key add -
               sudo apt update
@@ -95,13 +101,18 @@ before_install:
               docker run -d -p 8000:8000 dwmkerr/dynamodb:38 -inMemory
               while ! nc -zv 127.0.0.1 8000; do sleep 10; done
           fi
+    - |
+          if [[ "$TOXENV" == *cache ]]; then
+              docker run -d -p 11211:11211 memcached:alpine
+              while ! nc -zv 127.0.0.1 11211; do sleep 1; done
+          fi
     - |
           docker run -d -e executable=blob -t -p 10000:10000 --tmpfs /opt/azurite/folder:rw arafato/azurite:2.6.5
           while ! nc -zv 127.0.0.1 10000; do sleep 10; done
           export AZUREBLOCKBLOB_URL="azureblockblob://DefaultEndpointsProtocol=http;AccountName=devstoreaccount1;AccountKey=Eby8vdM02xNOcqFlqUwJPLlmEtlCDXJ1OUzFT50uSRZ6IFsuFq2UVErCz4I6tq/K1SZFPTOtr/KBHBeksoGMGw==;BlobEndpoint=http://127.0.0.1:10000/devstoreaccount1;"
     - |
           wget -qO - https://packages.couchbase.com/ubuntu/couchbase.key | sudo apt-key add -
-          sudo apt-add-repository -y 'deb http://packages.couchbase.com/ubuntu xenial xenial/main'
+          sudo apt-add-repository -y 'deb http://packages.couchbase.com/ubuntu bionic bionic/main'
           sudo apt-get update && sudo apt-get install -y libcouchbase-dev
 after_success:
   - |