CloudPubSub

A cloud message subscriber for client

The Google Cloud Pub/Sub service allows applications to exchange messages reliably, quickly, and asynchronously. To accomplish this, a data producer publishes messages to a Cloud Pub/Sub topic. A subscriber client then creates a subscription to that topic and consumes messages from the subscription. Cloud Pub/Sub persists messages that could not be delivered reliably for up to 7 days.

Core Steps:

(1) create a Virtual Evn.

(2) create Pub/Sub topic.

(3) create Pub/Sub subscriber for client.

(4) public message to topic.

(5) to delivery (indivisual) output topic meassage using a Pull Subsriber.

---

from step 1:

create a virtual env.

• 1.1, log in and activate the cloud shell, list the proj-id, then type the cmd line below.

  sudo apt-get update
  
  sudo apt-get install virtualenv
  // python virtual env is used to isolate the installation from sys.
  
  virtuallen -p python3 env
  
  source venv/bin/activate
  

from step 2:

create a pubsub client from cloud.

• 2.1, install google-cloud-pubsub to python pkg.

  pip install --upgrade google-cloud-pubsub
  

• 2.2, get pkg from github.

  git clone https://github.com/QueenieCplusplus/PubSub_Python_App.git
  
  cd PubSub_Python_App
  

• 2.3, get Google Proj ID

  export GLOBAL_CLOUD_PROJECT=GCP Project ID
  

• 2.4, edit/running code file

  cat publisher.py
  
  python publisher.py -h
  
  python publisher.py $GLOBAL_CLOUD_PROJECT create MyTopic
  

• 2.5, in cloud console, navigate to Big Data > Pub/Sub > topics we made.

  [result in UI]
  

  

to be continued...