dksnap
![Made by Kelda](https://kelda.io/img/dksnap/love-badge.svg)
Install |
Key Features |
FAQ |
Roadmap |
Contributing
dksnap
creates, views, and runs snapshots of Docker containers.
When testing locally we often use containers with test data. dksnap
allows
you to snapshot those containers at a good state, and roll back or forward as
needed.
For a full description check out this blogpost.
![](https://kelda.io/img/dksnap/dksnap-demo3.gif)
Install
Install on MacOS or Linux:
curl https://kelda.io/install-dksnap.sh | sh
Or download the latest release and
copy to your path.
Demo
Watch the demo, or try it yourself with
step-by-step instructions:
# Download the demo.
git clone https://github.com/kelda/dksnap.git
cd dksnap/demo
# Start the example application. You can access it in your browser at localhost:8080.
docker-compose up -d
# Use dksnap to create snapshots of the entries in the Mongo database.
dksnap
Key Features
Create Snapshots
Create a snapshot of any running Docker container. dksnap
works with any
container, but has extra features for select databases.
- Snapshots are volume aware. They will capture data in volumes as well as in
the container image.
- Snapshots are database aware. When snapshotting databases that implement the
plugin interface,
dksnap
will politely ask the
database process to dump its contents before creating a Docker image.
View Snapshots
dksnap
includes a terminal browser that provides a tree view of all your
snapshots along with diffs showing how they've changed over time.
Replace Running Containers
Replace a running Docker container with a snapshot taken in the past. dksnap
will automatically shut down the running container, boot the snapshot image,
and restart the container using the same Docker command arguments.
Other Features
Works With Any Container
By default, dksnap
creates snapshots by committing the container's
filesystem with docker commit
, and dumping the contents of all attached
volumes.
Database Awareness
dksnap
is database aware, meaning it knows how to politely dump and
restore and diff database contents for the following databases:
It has a plugin architecture making it easy to add more databases in the
future. Contributions welcome!
Docker Images
dksnap
images are simply docker
images with some additional metadata. This
means they can be viewed and manipulated using the standard docker
command
line tools.
Share Snapshots
dksnap
stores all of the snapshot information in a docker
image, so you can
share your snapshot by pushing it to a Docker registry just like you would any
other container image.
Volume Awareness
Snapshots are volume aware. The official database images all store their data
in volumes which docker commit
does not capture. dksnap
saves volumes in
addition to the container filesystem.
FAQ
How is this different than docker commit
?
dksnap
uses docker commit
for its generic snapshot approach to capture the
container’s filesystem. However, docker commit
has distinct limitations:
- It doesn't capture volumes, so it can't be used with most database docker
images.
- It isn't database aware. It doesn't politely save/restore database state
meaning it's prone to creating corrupted database images.
How is this different than a Docker image?
dksnap
uses Docker images as the storage format for its snapshots, which
makes them fully compatible with all of the things you would normally do with
an image (run, push, delete, etc). You could handcraft Docker images to mimic
dksnap
snapshots, but dksnap
makes it easy to create them from running
containers.
Roadmap
- Automated snapshot creation from production and staging databases in CI.
- A non-graphical CLI interface that's scriptable.
- Native support for additional databases.
- Snapshot of CPU and RAM state.
Contributing
dksnap
is still in alpha and under heavy development. Contributions are very
much welcome so please get involved. Check out the contribution
guidelines to get started.
Build
dksnap
requires being built with go
version 1.13 or later.
It uses Go Modules, and error wrapping.
git clone https://github.com/kelda/dksnap
cd dksnap
GO111MODULE=on go build .
./dksnap