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
).
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
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
.
fake-gcs-server defaults to HTTPS, but it can also be used with HTTP. The flag
-scheme
can be used to specify the protocol.
The binding port will be -port
(defaults to 4443
).
For example, the previous example could be changed to pass -scheme http
:
docker run -d --name fake-gcs-server -p 4443:4443 -v ${PWD}/examples/data:/data fsouza/fake-gcs-server -scheme http
And now we can curl it without the --insecure
flag and using https://
instead of https://
:
curl 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 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":[]}
To start both HTTPS and HTTP servers, pass -scheme both
.
HTTPS will bind to -port
(defaults to 4443
) and HTTP will bind to -port-http
(defaults to 8000
).
For example, the previous example could be changed to pass -scheme both
:
docker run -d --name fake-gcs-server -p 4443:4443 -p 8000:8000 -v ${PWD}/examples/data:/data fsouza/fake-gcs-server -scheme both
It is possible to use fake-gcs-server with signed URLs, although with a few caveats:
- No validation is made on the query params (signature, expiration ...)
- You need your client to modify the URL before passing it around (replace
storage.googleapis.com
with something that points to fake-gcs-server) - You need to configure fake-gcs-server to accept this local URL (by setting
-public-host
)
fake-gcs-server supports various features that can be configured through flags
upon start. Use the -help
flag to list all of them alongside their usage
instructions
docker run --rm fsouza/fake-gcs-server -help
For examples using SDK from multiple languages, check out the
examples
directory.
You may use docker build
to build the image locally instead of pulling it
from Docker Hub:
docker build -t fsouza/fake-gcs-server .