oittaa / fake-gcs-server

Google Cloud Storage emulator & testing library.

fake-gcs-server

fake-gcs-server provides an emulator for Google Cloud Storage API. It can be used as a library in Go projects and/or as a standalone binary/Docker image.

The library is available inside the package github.com/fsouza/fake-gcs-server/fakestorage and can be used from within test suites in Go package. The emulator is available as a binary that can be built manually, downloaded from the releases page or pulled from Docker Hub (docker pull fsouza/fake-gcs-server).

Using the emulator in Docker

You can stub/mock Google Cloud Storage as a standalone server (like the datastore/pubsub emulators) which is ideal for integration tests and/or tests in other languages you may want to run the fake-gcs-server inside a Docker container:

docker run -d --name fake-gcs-server -p 4443:4443 fsouza/fake-gcs-server

Preload data

In case you want to preload some data in fake-gcs-server just mount a folder in the container at /data:

docker run -d --name fake-gcs-server -p 4443:4443 -v ${PWD}/examples/data:/data fsouza/fake-gcs-server

Where the content of ${PWD}/examples/data is something like:

.
└── sample-bucket
    └── some_file.txt

To make sure everything works as expected you can execute these commands:

curl --insecure https://0.0.0.0:4443/storage/v1/b
{"kind":"storage#buckets","items":[{"kind":"storage#bucket","id":"sample-bucket","name":"sample-bucket"}],"prefixes":null}

curl --insecure https://0.0.0.0:4443/storage/v1/b/sample-bucket/o
{"kind":"storage#objects","items":[{"kind":"storage#object","name":"some_file.txt","id":"sample-bucket/some_file.txt","bucket":"sample-bucket","size":"33"}],"prefixes":[]}

This will result in one bucket called sample-bucket containing one object called some_file.txt.

Client library examples

For examples using the Python, Node.js and Go clients, check out the examples directory.

Building the image locally

You may use docker build to build the image locally instead of pulling it from Docker Hub:

docker build -t fsouza/fake-gcs-server .