"network: session_affinity:true " property of app.yaml file is not reflecting in google app engine

Question

I am using app.yaml file to configure my app engine. Below is the file.

runtime: java
env: flex

resources:
    memory_gb: 6.5
    cpu: 5
    disk_size_gb: 20
automatic_scaling: 
    min_num_instances: 6 
    max_num_instances: 8
    cpu_utilization: 
    target_utilization: 0.6
handlers:
    - url: /.*
    script: this field is required, but ignored

network:
     session_affinity: true

Now when I click the "view" link for the version list in the cloud console, I can see below config.

runtime: java
api_version: '1.0'
env: flexible
threadsafe: true
handlers:
   - url: /.*
   script: 'this field is required, but ignored'
automatic_scaling:
  cool_down_period: 120s
  min_num_instances: 6
  max_num_instances: 8
  cpu_utilization:
   target_utilization: 0.6
 network: {}
 resources:
     cpu: 5
     memory_gb: 6.5
    disk_size_gb: 20
 liveness_check:
    initial_delay_sec: 300
    check_interval_sec: 30
    timeout_sec: 4
    failure_threshold: 4
    success_threshold: 2
 readiness_check:
    check_interval_sec: 5
    timeout_sec: 4
    failure_threshold: 2
    success_threshold: 2
    app_start_timeout_sec: 300

So as you can see network property is still blank, if i change others parameters like cpu , min_num_instances all others properties are getting reflected except below one not sure why ?.

 network:
  session_affinity: true

Answer 1

Actually this is a known issue for App Engine, the status can be tracked at this link

You can use gcloud beta app deploy as a workaround to get the session affinity working until the issue is resolved