## Installing Snap

The Snap Store has a snap package for [Autopsy](https://snapcraft.io/autopsy).  You can install Autopsy by running `sudo snap install autopsy`.  You can also install the snap from our [release section](https://github.com/sleuthkit/autopsy/releases) by downloading the `.snap` file asset and locally running  `sudo snap install --dangerous /path/to/autopsy.snap`.  The `--dangerous` needs to be specified because the snap package isn't signed (see [install modes](https://snapcraft.io/docs/install-modes#heading--dangerous) for more information).  Also, look at the [connections](#setting-snap-connections) section for important permission information.

## Setting Snap Connections

By default, snap doesn't allow certain interactions with the operating system.  These [Super-privileged connections](https://snapcraft.io/docs/super-privileged-interfaces) may need to be connected.  This can be done manually by running `snap connections autopsy` to determine any missing connections, and then running `snap connect autopsy:home` replacing `home` with the name of the plug.  Another option is to run this script, which will connect all missing plugs: `snap connections autopsy | sed -nE 's/^[^ ]* *([^ ]*) *- *- *$/\1/p' | xargs -I{} sudo snap connect {}`.  More information on interface management can be found at the [snapcraft website](https://snapcraft.io/docs/interface-management).

## Running Autopsy

After installing Autopsy, you should be able to run with `autopsy`.  Snap also typically installs a `.desktop` file for your launcher.  If you want to perform an ingest on a local disk, you will need to run with permissions for disks in the `/dev` folder.  On Ubuntu, that command will be `sudo -g disk autopsy` as `disk` group permissions will give access to that folder.

## Generating The Snap Package

A [snap package](https://snapcraft.io/) of Autopsy can be generated using the [`snapcraft.yml`](./snapcraft.yaml) file.  You will need [snapcraft](https://snapcraft.io/) on your system and [lxd](https://snapcraft.io/lxd) works well for virtualization while building the snap package.  Since snapcraft needs virtualization to create the snap package, your computer's hardware will need to support virtualization and any relevant settings will need to be enabled.  From testing as of November 2022, VirtualBox and WSL are not good build environments.  Once the development environment has been set up, a snap package can be built with this command: `snapcraft --use-lxd --debug` run from this directory.  If you want to build async, but still get logs, you can run something like this: `nohup snapcraft --use-lxd --debug > ./output.log 2>&1 < /dev/null &`.

## Updating Versions for Snap

The version of Autopsy in the [`snapcraft.yml`](./snapcraft.yaml) can be updated by calling [`version_update.py`](./version_update/version_update.py) with a command like `python version_update.py -s sleuthkit_release_tag -a autopsy_release_tag -v snapcraft_version_name`.  You will likely need to install the python dependencies in the [requirements.txt](./version_update/requirements.txt) with a command like: `pip install -r requirements.txt`.

The version of Autopsy can be updated manually by modifying fields relating to git repositories and commits in [`snapcraft.yml`](./snapcraft.yaml) under `parts.autopsy` and `parts.sleuthkit`.  Specifically `source`, `source-branch`, and `source-tag`.  More information can be found [here](https://snapcraft.io/docs/snapcraft-yaml-reference).

## Troubleshooting

### Solr won't run

An error like "Local Solr Server did not respond to status request" or something similar, may indicate that not all snap connections may have been connected.  By default, snap doesn't allow certain interactions with the operating system.  You may need to manually connect these connections.  See the [connections section](#setting-snap-connections) for more information.

### There are no local disks for processing

Autopsy looks at the block devices in the `/dev` directory for local disks to process.  If autopsy can't read block devices in that directory, it won't show the local disk.  You may need to set the connections for the Autopsy snap that aren't set manually.  See the [connections section](#setting-snap-connections) for more information.  You may also need to run autopsy with the right OS permissions.  In most instances, starting autopsy with a command like `sudo -g disk autopsy` should give autopsy the right permissions to view local disks.  This assumes that the `disk` group has read rights to local disks (i.e. `/dev/sda1`).  Appropriate permissions can be determined by running something like `ls -l /dev` looking for the permissions required for the local disks.  Then autopsy should be started in such a way that the `$USER` and `$HOME` are preserved (i.e. running as root may be problematic), but the user account and, consequently, autopsy, has sufficient permissions to access local disk block devices.

### Out of space error when building snap

It might be worth reinitializing lxd for building the image.  This can be done by running `sudo snap remove --purge lxd` removing lxd and cached data.  Run `sudo snap install lxd` and then `sudo snap lxd init` with defaults to reinitialize.