Deploying container images in GCP - Step-by-Step Execution

Process Flow - Deploying container images

Write Dockerfile

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Build container image

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Tag image for registry

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Push image to Container Registry

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Create deployment using image

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Service starts running container

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Monitor and update deployment

This flow shows how you create a container image, upload it to Google Container Registry, and deploy it to run as a service.

Execution Sample

GCP

docker build -t gcr.io/my-project/my-app:v1 .
docker push gcr.io/my-project/my-app:v1
gcloud run deploy my-app --image gcr.io/my-project/my-app:v1 --region us-central1

Builds a container image, pushes it to Google Container Registry, and deploys it to Cloud Run.

Process Table

Step	Action	Input/Command	Result/Output
1	Build container image	docker build -t gcr.io/my-project/my-app:v1 .	Image 'gcr.io/my-project/my-app:v1' created locally
2	Push image to registry	docker push gcr.io/my-project/my-app:v1	Image uploaded to Google Container Registry
3	Deploy container image	gcloud run deploy my-app --image gcr.io/my-project/my-app:v1 --region us-central1	Cloud Run service 'my-app' deployed and running
4	Verify deployment	gcloud run services describe my-app --region us-central1	Service status: Ready, URL available
5	Update deployment	docker build -t gcr.io/my-project/my-app:v2 .	New image 'gcr.io/my-project/my-app:v2' built locally
6	Push updated image	docker push gcr.io/my-project/my-app:v2	Image 'v2' uploaded to registry
7	Deploy updated image	gcloud run deploy my-app --image gcr.io/my-project/my-app:v2 --region us-central1	Service updated to use image 'v2'
8	Verify update	gcloud run services describe my-app --region us-central1	Service status: Ready, running updated image
9	Exit	N/A	Deployment complete and running

💡 Deployment is complete when the service status is Ready and running the desired container image.

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 5	After Step 6	After Step 7	Final
Container Image Tag	None	gcr.io/my-project/my-app:v1 (built)	gcr.io/my-project/my-app:v1 (pushed)	gcr.io/my-project/my-app:v1 (deployed)	gcr.io/my-project/my-app:v2 (built)	gcr.io/my-project/my-app:v2 (pushed)	gcr.io/my-project/my-app:v2 (deployed)	gcr.io/my-project/my-app:v2 (running)
Service Status	None	None	None	Ready (running v1)	Ready (running v1)	Ready (running v1)	Ready (running v2)	Ready (running v2)

Key Moments - 3 Insights

Why do we tag the container image before pushing it?

Tagging names the image with the registry path so it knows where to upload. See execution_table step 1 and 2 where the image is built with a tag and then pushed.

What happens if the deployment command uses an image tag that is not pushed?

The deployment will fail because the image is not found in the registry. The image must be pushed first as shown in step 2 before deploying in step 3.

How do we update the running service with a new container version?

Build and push a new image with a new tag (steps 5 and 6), then deploy again with the new image tag (step 7). The service status updates accordingly (step 8).

Visual Quiz - 3 Questions

Look at the execution_table, what is the container image tag after step 3?

A None

B gcr.io/my-project/my-app:v1 (deployed)

C gcr.io/my-project/my-app:v2 (built)

D gcr.io/my-project/my-app:v2 (deployed)

💡 Hint

Check the 'Container Image Tag' row in variable_tracker after step 3.

At which step does the service start running the updated container image?

A Step 7

B Step 3

C Step 5

D Step 2

💡 Hint

Look at the 'Service Status' variable in variable_tracker after step 7.

If you skip pushing the image (step 2), what will happen at deployment (step 3)?

A Deployment succeeds with local image

B Deployment uses previous image automatically

C Deployment fails due to missing image in registry

D Deployment ignores image tag

💡 Hint

Refer to key_moments explanation about pushing images before deployment.

Concept Snapshot

Deploy container images by:
1. Building image locally with a tag for registry
2. Pushing image to Google Container Registry
3. Deploying image to Cloud Run or other service
4. Updating by repeating build, push, deploy with new tag
Always push before deploy to avoid errors.

Full Transcript

Deploying container images in Google Cloud involves building a container image locally using Docker, tagging it with the registry path, pushing it to Google Container Registry, and then deploying it to a service like Cloud Run. The deployment command uses the image tag to pull the image from the registry and run it. To update the service, build and push a new image with a new tag, then deploy again with that tag. The service status changes to Ready when running the container. Skipping the push step causes deployment failure because the image is not found in the registry.