Example 2: Update README.md

[jnewland]

This build uses the layer cache for all steps in our Dockerfile above the ADD README.md README.md line. Since README.md has changed, all subsequent steps in the Dockerfile are executed:

starting build "2029ef3f-4048-4a9f-9111-4f946c72a6d3"

FETCHSOURCE
Fetching storage object: gs://677203284384.cloudbuild-source.googleusercontent.com/54cd8aabf8fbb06352e4f0c2ac3d4c0ed2bad6ab-06869a1a-2faf-442a-b221-9c7a3ada2262.tar.gz#1535548293395948
Copying gs://677203284384.cloudbuild-source.googleusercontent.com/54cd8aabf8fbb06352e4f0c2ac3d4c0ed2bad6ab-06869a1a-2faf-442a-b221-9c7a3ada2262.tar.gz#1535548293395948...
/ [0 files][ 0.0 B/ 1.6 KiB] 
/ [1 files][ 1.6 KiB/ 1.6 KiB] 
Operation completed over 1 objects/1.6 KiB. 
tar: Substituting `.' for empty member name
BUILD
Starting Step #0
Step #0: Already have image (with digest): gcr.io/cloud-builders/docker
Step #0: Error response from daemon: manifest for gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:example-2 not found
Step #0: master: Pulling from urcomputeringpal/cloudbuild-branch-based-caching
Step #0: 8e3ba11ec2a2: Already exists
Step #0: dbb12c9c661c: Pulling fs layer
Step #0: 0341b007c935: Pulling fs layer
Step #0: 7e7f7f86258a: Pulling fs layer
Step #0: 72994e4e6a86: Pulling fs layer
Step #0: 72994e4e6a86: Waiting
Step #0: 7e7f7f86258a: Verifying Checksum
Step #0: 7e7f7f86258a: Download complete
Step #0: 0341b007c935: Verifying Checksum
Step #0: 0341b007c935: Download complete
Step #0: dbb12c9c661c: Verifying Checksum
Step #0: dbb12c9c661c: Download complete
Step #0: dbb12c9c661c: Pull complete
Step #0: 0341b007c935: Pull complete
Step #0: 72994e4e6a86: Verifying Checksum
Step #0: 72994e4e6a86: Download complete
Step #0: 7e7f7f86258a: Pull complete
Step #0: 72994e4e6a86: Pull complete
Step #0: Digest: sha256:96babe6faab5a5ca4e1fa4ebfd35ab493b5dc44c342585bcda6a04eb7ec90989
Step #0: Status: Downloaded newer image for gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:master
Finished Step #0
Starting Step #1
Step #1: Already have image (with digest): gcr.io/cloud-builders/docker
Step #1: Sending build context to Docker daemon 7.68kB

Step #1: Step 1/6 : FROM alpine
Step #1: latest: Pulling from library/alpine
Step #1: Digest: sha256:0873c923e00e0fd2ba78041bfb64a105e1ecb7678916d1f7776311e45bf5634b
Step #1: Status: Downloaded newer image for alpine:latest
Step #1: ---> 11cd0b38bc3c
Step #1: Step 2/6 : WORKDIR /app
Step #1: ---> Using cache
Step #1: ---> 7212ccc34a7c
Step #1: Step 3/6 : ADD README.md README.md
Step #1: ---> a00c7068347a
Step #1: Step 4/6 : RUN apk update && apk add ca-certificates && rm -rf /var/cache/apk/*
Step #1: ---> Running in 85a581094eca
Step #1: fetch http://dl-cdn.alpinelinux.org/alpine/v3.8/main/x86_64/APKINDEX.tar.gz
Step #1: fetch http://dl-cdn.alpinelinux.org/alpine/v3.8/community/x86_64/APKINDEX.tar.gz
Step #1: v3.8.0-95-g244b823930 [http://dl-cdn.alpinelinux.org/alpine/v3.8/main]
Step #1: v3.8.0-95-g244b823930 [http://dl-cdn.alpinelinux.org/alpine/v3.8/community]
Step #1: OK: 9542 distinct packages available
Step #1: (1/1) Installing ca-certificates (20171114-r3)
Step #1: Executing busybox-1.28.4-r0.trigger
Step #1: Executing ca-certificates-20171114-r3.trigger
Step #1: OK: 5 MiB in 14 packages
Step #1: Removing intermediate container 85a581094eca
Step #1: ---> aad81075a6b2
Step #1: Step 5/6 : ADD run.sh run.sh
Step #1: ---> 0c545410f69b
Step #1: Step 6/6 : ENTRYPOINT ["/app/run.sh"]
Step #1: ---> Running in 9ef85f730a20
Step #1: Removing intermediate container 9ef85f730a20
Step #1: ---> 2dd89ba100c7
Step #1: Successfully built 2dd89ba100c7
Step #1: Successfully tagged gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:example-2
Step #1: Successfully tagged gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:54cd8aabf8fbb06352e4f0c2ac3d4c0ed2bad6ab
Finished Step #1
PUSH
Pushing gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:example-2
The push refers to repository [gcr.io/urcomputeringpal/cloudbuild-branch-based-caching]
f8d0b348568a: Preparing
b004ac694d5d: Preparing
7f565aa32c3f: Preparing
9a20ec34bec2: Preparing
73046094a9b8: Preparing
73046094a9b8: Layer already exists
9a20ec34bec2: Layer already exists
7f565aa32c3f: Pushed
b004ac694d5d: Pushed
f8d0b348568a: Pushed
example-2: digest: sha256:4394ce600f376b8e78d42e3d3897133ba7804d4876cadc342cf3c1ea660b30e3 size: 1359
Pushing gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:54cd8aabf8fbb06352e4f0c2ac3d4c0ed2bad6ab
The push refers to repository [gcr.io/urcomputeringpal/cloudbuild-branch-based-caching]
f8d0b348568a: Preparing
b004ac694d5d: Preparing
7f565aa32c3f: Preparing
9a20ec34bec2: Preparing
73046094a9b8: Preparing
f8d0b348568a: Layer already exists
7f565aa32c3f: Layer already exists
b004ac694d5d: Layer already exists
9a20ec34bec2: Layer already exists
73046094a9b8: Layer already exists
54cd8aabf8fbb06352e4f0c2ac3d4c0ed2bad6ab: digest: sha256:4394ce600f376b8e78d42e3d3897133ba7804d4876cadc342cf3c1ea660b30e3 size: 1359
DONE

[jnewland]

dfc2370 changes run.sh on this branch. Its build demonstrates how each branch maintains its own layer cache - even though both README.md and run.sh have now changed on this branch, the build for dfc2370 leveraged the build cache created by the build of 54cd8aa:

starting build "aee435f0-d493-469f-a1ce-ae90c4594ee0"

FETCHSOURCE
Fetching storage object: gs://677203284384.cloudbuild-source.googleusercontent.com/dfc2370f3f82a6a09b8666bb0322d0f0d6b27b66-72189eba-3d3a-482a-8eb6-510e86e61ae9.tar.gz#1535548699402138
Copying gs://677203284384.cloudbuild-source.googleusercontent.com/dfc2370f3f82a6a09b8666bb0322d0f0d6b27b66-72189eba-3d3a-482a-8eb6-510e86e61ae9.tar.gz#1535548699402138...
/ [0 files][ 0.0 B/ 1.6 KiB] 
/ [1 files][ 1.6 KiB/ 1.6 KiB] 
Operation completed over 1 objects/1.6 KiB. 
tar: Substituting `.' for empty member name
BUILD
Starting Step #0
Step #0: Already have image (with digest): gcr.io/cloud-builders/docker
Step #0: example-2: Pulling from urcomputeringpal/cloudbuild-branch-based-caching
Step #0: 8e3ba11ec2a2: Already exists
Step #0: dbb12c9c661c: Pulling fs layer
Step #0: f18cac60ee69: Pulling fs layer
Step #0: d5b208066928: Pulling fs layer
Step #0: 1042d7d9fc0d: Pulling fs layer
Step #0: 1042d7d9fc0d: Waiting
Step #0: f18cac60ee69: Verifying Checksum
Step #0: f18cac60ee69: Download complete
Step #0: dbb12c9c661c: Verifying Checksum
Step #0: dbb12c9c661c: Download complete
Step #0: d5b208066928: Verifying Checksum
Step #0: d5b208066928: Download complete
Step #0: dbb12c9c661c: Pull complete
Step #0: f18cac60ee69: Pull complete
Step #0: 1042d7d9fc0d: Verifying Checksum
Step #0: 1042d7d9fc0d: Download complete
Step #0: d5b208066928: Pull complete
Step #0: 1042d7d9fc0d: Pull complete
Step #0: Digest: sha256:4394ce600f376b8e78d42e3d3897133ba7804d4876cadc342cf3c1ea660b30e3
Step #0: Status: Downloaded newer image for gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:example-2
Step #0: master: Pulling from urcomputeringpal/cloudbuild-branch-based-caching
Step #0: 8e3ba11ec2a2: Already exists
Step #0: dbb12c9c661c: Already exists
Step #0: 0341b007c935: Pulling fs layer
Step #0: 7e7f7f86258a: Pulling fs layer
Step #0: 72994e4e6a86: Pulling fs layer
Step #0: 0341b007c935: Verifying Checksum
Step #0: 0341b007c935: Download complete
Step #0: 72994e4e6a86: Verifying Checksum
Step #0: 72994e4e6a86: Download complete
Step #0: 7e7f7f86258a: Verifying Checksum
Step #0: 7e7f7f86258a: Download complete
Step #0: 0341b007c935: Pull complete
Step #0: 7e7f7f86258a: Pull complete
Step #0: 72994e4e6a86: Pull complete
Step #0: Digest: sha256:96babe6faab5a5ca4e1fa4ebfd35ab493b5dc44c342585bcda6a04eb7ec90989
Step #0: Status: Downloaded newer image for gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:master
Finished Step #0
Starting Step #1
Step #1: Already have image (with digest): gcr.io/cloud-builders/docker
Step #1: Sending build context to Docker daemon 7.68kB

Step #1: Step 1/6 : FROM alpine
Step #1: latest: Pulling from library/alpine
Step #1: Digest: sha256:0873c923e00e0fd2ba78041bfb64a105e1ecb7678916d1f7776311e45bf5634b
Step #1: Status: Downloaded newer image for alpine:latest
Step #1: ---> 11cd0b38bc3c
Step #1: Step 2/6 : WORKDIR /app
Step #1: ---> Using cache
Step #1: ---> 7212ccc34a7c
Step #1: Step 3/6 : ADD README.md README.md
Step #1: ---> Using cache
Step #1: ---> 42e3fe19606d
Step #1: Step 4/6 : RUN apk update && apk add ca-certificates && rm -rf /var/cache/apk/*
Step #1: ---> Using cache
Step #1: ---> 931315c874ba
Step #1: Step 5/6 : ADD run.sh run.sh
Step #1: ---> 8eac5384709e
Step #1: Step 6/6 : ENTRYPOINT ["/app/run.sh"]
Step #1: ---> Running in fbb5c8950328
Step #1: Removing intermediate container fbb5c8950328
Step #1: ---> ca754dd5e0a5
Step #1: Successfully built ca754dd5e0a5
Step #1: Successfully tagged gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:example-2
Step #1: Successfully tagged gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:dfc2370f3f82a6a09b8666bb0322d0f0d6b27b66
Finished Step #1
PUSH
Pushing gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:example-2
The push refers to repository [gcr.io/urcomputeringpal/cloudbuild-branch-based-caching]
951aa4cef3e6: Preparing
b004ac694d5d: Preparing
7f565aa32c3f: Preparing
9a20ec34bec2: Preparing
73046094a9b8: Preparing
9a20ec34bec2: Layer already exists
7f565aa32c3f: Layer already exists
b004ac694d5d: Layer already exists
73046094a9b8: Layer already exists
951aa4cef3e6: Pushed
example-2: digest: sha256:760ed1f1b93bea5da34570aaf1f228b910392636b9bf256c9652a42a67747fac size: 1359
Pushing gcr.io/urcomputeringpal/cloudbuild-branch-based-caching:dfc2370f3f82a6a09b8666bb0322d0f0d6b27b66
The push refers to repository [gcr.io/urcomputeringpal/cloudbuild-branch-based-caching]
951aa4cef3e6: Preparing
b004ac694d5d: Preparing
7f565aa32c3f: Preparing
9a20ec34bec2: Preparing
73046094a9b8: Preparing
9a20ec34bec2: Layer already exists
951aa4cef3e6: Layer already exists
7f565aa32c3f: Layer already exists
b004ac694d5d: Layer already exists
73046094a9b8: Layer already exists
dfc2370f3f82a6a09b8666bb0322d0f0d6b27b66: digest: sha256:760ed1f1b93bea5da34570aaf1f228b910392636b9bf256c9652a42a67747fac size: 1359
DONE