Cloud Run service concept in GCP - Step-by-Step Execution

Process Flow - Cloud Run service concept

Write containerized app

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Push container image to registry

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Create Cloud Run service

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Cloud Run deploys container

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Service receives HTTP request

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Container handles request and responds

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Scale up/down based on traffic

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End

This flow shows how a containerized app is deployed to Cloud Run, which runs it on demand and scales automatically.

Execution Sample

GCP

gcloud run deploy my-service --image gcr.io/my-project/my-image --platform managed

Deploys a container image as a Cloud Run service that runs and scales automatically.

Process Table

Step	Action	Input/Condition	Result/Output
1	Write containerized app	App code + Dockerfile	Container image ready
2	Push container image	Container image	Image stored in registry
3	Deploy Cloud Run service	Image URL	Service created and running
4	Send HTTP request	Request arrives at service URL	Request routed to container
5	Container handles request	Request data	Response sent back
6	Scale based on traffic	Number of requests	Containers scale up/down
7	No requests	Idle state	Containers scale to zero
8	Stop	No more requests	Service waits for next request

💡 Execution stops when no requests are received and containers scale to zero, waiting for new requests.

Status Tracker

Variable	Start	After Step 2	After Step 3	After Step 6	Final
Container Image	Not built	Built and pushed	Used by Cloud Run	Used for scaling	Stored in registry
Cloud Run Service	Not created	Not created	Created and running	Scaling containers	Waiting for requests
Containers Running	0	0	1 (initial)	Varies with traffic	0 (idle)

Key Moments - 3 Insights

Why does Cloud Run scale containers to zero when idle?

Cloud Run scales to zero to save resources and cost when no requests are received, as shown in execution_table step 7.

How does Cloud Run know which container image to run?

The container image URL provided during deployment (step 3) tells Cloud Run which image to use.

What happens when a new request arrives and no containers are running?

Cloud Run automatically starts a container to handle the request, scaling from zero as in step 4 and 5.

Visual Quiz - 3 Questions

Look at the execution_table, at which step does Cloud Run create the service?

A Step 2

B Step 3

C Step 5

D Step 7

💡 Hint

Check the 'Action' column for 'Deploy Cloud Run service' in execution_table.

According to variable_tracker, what is the number of running containers after step 6?

A Varies with traffic

B 1 (initial)

C 0

D Not created

💡 Hint

Look at the 'Containers Running' row under 'After Step 6' in variable_tracker.

If no requests come in, what does Cloud Run do according to the execution_table?

A Deletes the service

B Keeps containers running

C Scales containers to zero

D Returns error

💡 Hint

See step 7 in execution_table about scaling behavior when idle.

Concept Snapshot

Cloud Run runs containerized apps on demand.
Deploy by pushing container image and creating a service.
Service handles HTTP requests and scales automatically.
Scales to zero when idle to save cost.
Simple command: gcloud run deploy --image IMAGE_URL

Full Transcript

Cloud Run lets you run your containerized app without managing servers. First, you write your app and package it into a container image. Then you push this image to a container registry. Next, you deploy the image to Cloud Run, which creates a service. When someone sends an HTTP request to the service URL, Cloud Run starts a container to handle it. If many requests come, Cloud Run automatically adds more containers. When no requests come, it scales down to zero containers to save resources. This process is simple and automatic, making it easy to run apps in the cloud.