dive

A tool for exploring a docker image, layer contents, and discovering ways to shrink your Docker image size.

To analyze a Docker image simply run dive with an image tag/id/digest:

dive <your-image-tag>

or if you want to build your image then jump straight into analyzing it:

dive build -t <some-tag> .

Additionally you can run this in your CI pipeline to ensure you're keeping wasted space to a minimum (this skips the UI):

CI=true dive <your-image>

This is beta quality! Feel free to submit an issue if you want a new feature or find a bug :)

Basic Features

Show Docker image contents broken down by layer

As you select a layer on the left, you are shown the contents of that layer combined with all previous layers on the right. Also, you can fully explore the file tree with the arrow keys.

Indicate what's changed in each layer

Files that have changed, been modified, added, or removed are indicated in the file tree. This can be adjusted to show changes for a specific layer, or aggregated changes up to this layer.

Estimate "image efficiency"

The lower left pane shows basic layer info and an experimental metric that will guess how much wasted space your image contains. This might be from duplicating files across layers, moving files across layers, or not fully removing files. Both a percentage "score" and total wasted file space is provided.

Quick build/analysis cycles

You can build a Docker image and do an immediate analysis with one command: dive build -t some-tag .

You only need to replace your docker build command with the same dive build command.

CI Integration Analyze and image and get a pass/fail result based on the image efficiency and wasted space. Simply set CI=true in the environment when invoking any valid dive command.

Installation

Ubuntu/Debian

wget https://github.com/wagoodman/dive/releases/download/v0.6.0/dive_0.6.0_linux_amd64.deb
sudo apt install ./dive_0.6.0_linux_amd64.deb

RHEL/Centos

curl -OL https://github.com/wagoodman/dive/releases/download/v0.6.0/dive_0.6.0_linux_amd64.rpm
rpm -i dive_0.6.0_linux_amd64.rpm

Arch Linux

Available as dive in the Arch User Repository (AUR).

yay -S dive

The above example assumes yay as the tool for installing AUR packages. Note: the AUR repository is not controlled by the dive project maintainer.

Mac

brew tap wagoodman/dive
brew install dive

or download the latest Darwin build from the releases page.

Windows

Download the latest release.

Go tools Requires Go version 1.9 or higher.

go get github.com/wagoodman/dive

Note: installing in this way you will not see a proper version when running dive -v.

Docker

docker pull wagoodman/dive

or

docker pull quay.io/wagoodman/dive

When running you'll need to include the docker client binary and socket file:

docker run --rm -it \
    -v /var/run/docker.sock:/var/run/docker.sock \
    wagoodman/dive:latest <dive arguments...>

Docker for Windows (showing PowerShell compatible line breaks; collapse to a single line for Command Prompt compatibility)

docker run --rm -it `
    -v /var/run/docker.sock:/var/run/docker.sock `
    wagoodman/dive:latest <dive arguments...>

Note: depending on the version of docker you are running locally you may need to specify the docker API version as an environment variable:

   DOCKER_API_VERSION=1.37 dive ...

or if you are running with a docker image:

docker run --rm -it \
    -v /var/run/docker.sock:/var/run/docker.sock \
    -e DOCKER_API_VERSION=1.37
    wagoodman/dive:latest <dive arguments...>

CI Integration

When running dive with the environment variable CI=true then the dive UI will be bypassed and will instead analyze your docker image, giving it a pass/fail indication via return code. Currently there are three metrics supported via a .dive-ci file that you can put at the root of your repo:

rules:
  # If the efficiency is measured below X%, mark as failed.
  # Expressed as a percentage between 0-1.
  lowestEfficiency: 0.95

  # If the amount of wasted space is at least X or larger than X, mark as failed.
  # Expressed in B, KB, MB, and GB.
  highestWastedBytes: 20MB

  # If the amount of wasted space makes up for X% or more of the image, mark as failed.
  # Note: the base image layer is NOT included in the total image size.
  # Expressed as a percentage between 0-1; fails if the threshold is met or crossed.
  highestUserWastedPercent: 0.20

You can override the CI config path with the --ci-config option.

KeyBindings

Key Binding	Description
Ctrl + C	Exit
Tab or Ctrl + Space	Switch between the layer and filetree views
Ctrl + F	Filter files
Ctrl + A	Layer view: see aggregated image modifications
Ctrl + L	Layer view: see current layer modifications
Space	Filetree view: collapse/uncollapse a directory
Ctrl + A	Filetree view: show/hide added files
Ctrl + R	Filetree view: show/hide removed files
Ctrl + M	Filetree view: show/hide modified files
Ctrl + U	Filetree view: show/hide unmodified files
PageUp	Filetree view: scroll up a page
PageDown	Filetree view: scroll down a page

UI Configuration

No configuration is necessary, however, you can create a config file and override values:

log:
  enabled: true
  path: ./dive.log
  level: info

# Note: you can specify multiple bindings by separating values with a comma.
# Note: UI hinting is derived from the first binding
keybinding:
  # Global bindings
  quit: ctrl+c
  toggle-view: tab, ctrl+space
  filter-files: ctrl+f, ctrl+slash

  # Layer view specific bindings  
  compare-all: ctrl+a
  compare-layer: ctrl+l

  # File view specific bindings
  toggle-collapse-dir: space
  toggle-added-files: ctrl+a
  toggle-removed-files: ctrl+r
  toggle-modified-files: ctrl+m
  toggle-unmodified-files: ctrl+u
  page-up: pgup
  page-down: pgdn
  
diff:
  # You can change the default files show in the filetree (right pane). All diff types are shown by default. 
  hide:
    - added
    - removed
    - changed
    - unchanged

filetree:
  # The default directory-collapse state
  collapse-dir: false

  # The percentage of screen width the filetree should take on the screen (must be >0 and <1)
  pane-width: 0.5

layer:
  # Enable showing all changes from this layer and ever previous layer
  show-aggregated-changes: false

dive will search for configs in the following locations:

• ~/.dive.yaml
• $XDG_CONFIG_HOME/dive.yaml
• ~/.config/dive.yaml