Checklist

Issue can be reproduced on the latest stable commit in master - 8d61a78c76a096597421a8e9db2878d4381dd6a

Steps to reproduce

• Create fresh python 3.8 virtualenv
• Install Faust pip install git+https://github.com/robinhood/faust@38d61a78c76a096597421a8e9db2878d4381dd6a
• Create an app with agent. The example from the quick start is enough.

  import faust
  
  app = faust.App(
      'hello-world',
      broker='kafka://localhost:9092',
      value_serializer='raw',
  )
  
  greetings_topic = app.topic('greetings')
  
  @app.agent(greetings_topic)
  async def greet(greetings):
      async for greeting in greetings:
          print(greeting)
  

• Launch the worker and let it create Kafka topic.

  faust -A hello_world worker -l warn
  

• Send a message to the Kafka topic

  kafka-console-producer  --broker-list localhost:9092 --topic greetings
  >hello
  

• Stop the worker, and reset log offset to the latest

  kafka-consumer-groups --bootstrap-server localhost:9092 --group hello-world --reset-offsets --to-latest --execute --all-topics
  

• Launch the worker again

  faust -A hello_world worker -l warn
  

• Produce 2 more messages to the Kafka topic

  kafka-console-producer  --broker-list localhost:9092 --topic greetings
  >hello 1, will be ignored
  >hello 2, will be printed
  

Expected behavior

• Both messages should be printed in the worker console.

  ┌ƒaµS† v1.11.0a1────────────────────────────────────────────────────────┐
  │ id          │ hello-world                                             │
  │ transport   │ [URL('kafka://localhost:9092')]                         │
  │ store       │ memory:                                                 │
  │ web         │ http://maxims-macbook-pro.local:6066                    │
  │ log         │ -stderr- (warn)                                         │
  │ pid         │ 49793                                                   │
  │ hostname    │ Maxims-MacBook-Pro.local                                │
  │ platform    │ CPython 3.8.0 (Darwin x86_64)                           │
  │ drivers     │                                                         │
  │   transport │ aiokafka=1.1.6                                          │
  │   web       │ aiohttp=3.6.2                                           │
  │ datadir     │ /Users/shamanu4/projects/faust_test/hello-world-data    │
  │ appdir      │ /Users/shamanu4/projects/faust_test/hello-world-data/v1 │
  └─────────────┴─────────────────────────────────────────────────────────┘
  starting➢ 😊
  [2020-07-21 12:51:38,541] [49793] [WARNING] b'hello 1, will be ignored'
  [2020-07-21 12:51:39,399] [49793] [WARNING] b'hello 2, will be printed'
  

Actual behavior

• First message is missing

  ┌ƒaµS† v1.11.0a1────────────────────────────────────────────────────────┐
  │ id          │ hello-world                                             │
  │ transport   │ [URL('kafka://localhost:9092')]                         │
  │ store       │ memory:                                                 │
  │ web         │ http://maxims-macbook-pro.local:6066                    │
  │ log         │ -stderr- (warn)                                         │
  │ pid         │ 49793                                                   │
  │ hostname    │ Maxims-MacBook-Pro.local                                │
  │ platform    │ CPython 3.8.0 (Darwin x86_64)                           │
  │ drivers     │                                                         │
  │   transport │ aiokafka=1.1.6                                          │
  │   web       │ aiohttp=3.6.2                                           │
  │ datadir     │ /Users/shamanu4/projects/faust_test/hello-world-data    │
  │ appdir      │ /Users/shamanu4/projects/faust_test/hello-world-data/v1 │
  └─────────────┴─────────────────────────────────────────────────────────┘
  starting➢ 😊
  [2020-07-21 12:51:39,399] [49793] [WARNING] b'hello 2, will be printed'
  

Versions

• Python version - 3.8.0
• Faust version - faust @ git+https://github.com/robinhood/faust@38d61a78c76a096597421a8e9db2878d4381dd6a
• Operating system - MacOS Catalina 10.15.6
• Kafka version - 2.2.1