Filesystem Layout

Overview of runtime directory structure

This page describes the filesystem directory layout used internally by LocalStack.

Filesystem layout

LocalStack uses following directory layout when running within a container.

/
├── etc
│   └── localstack
│       └── init
├── usr
│   └── lib
│       └── localstack
└── var
    └── lib
        └── localstack  <- the LocalStack volume directory root
            ├── cache
            ├── lib
            ├── logs
            ├── state
            └── tmp

Directory contents

LocalStack volume directory

  • /var/lib/localstack: the LocalStack volume directory root
  • /var/lib/localstack/lib: variable packages (like extensions or lazy-loaded third-party dependencies)
  • /var/lib/localstack/logs: logs for recent LocalStack runs
  • /var/lib/localstack/state: contains the state of services if persistence is enabled (such as OpenSearch cluster data)
  • /var/lib/localstack/tmp: temporary data that is not expected to survive LocalStack runs (may be cleared when LocalStack starts or stops)
  • /var/lib/localstack/cache: temporary data that is expected to survive LocalStack runs (is not cleared when LocalStack starts or stops)

Configuration

  • /etc/localstack: configuration directory
  • /etc/localstack/init: root directory for initialization hooks

Static libraries

  • /usr/lib/localstack: static third-party packages installed into the container images

LocalStack volume

For LocalStack to function correctly, the LocalStack volume must be mounted from the host into the container at /var/lib/localstack.

Using docker-compose

When using Docker Compose, this can be achieved using following:

volumes:
  - "${LOCALSTACK_VOLUME_DIR:-./volume}:/var/lib/localstack"

${LOCALSTACK_VOLUME_DIR} could be an arbitrary location on the host, e.g., ./volume. In this case, the effective layout would be something like:

$ tree -L 4 ./volume
.
└── localstack
    ├── cache
    │   ├── machine.json
    │   ├── server.test.pem
    │   ├── server.test.pem.crt
    │   └── server.test.pem.key
    ├── lib
    │   └── opensearch
    │       └── 1.1.0
    ├── logs
    │   ├── localstack_infra.err
    │   └── localstack_infra.log
    ├── state
    │   └── startup_info.json
    └── tmp
        └── zipfile.4986fb95

Using the CLI

When using the CLI to start LocalStack, the volume directory can be configured via the LOCALSTACK_VOLUME_DIR. It should point to a directory on the host which is then automatically mounted into /var/lib/localstack. The defaults are:

  • Mac: ~/Library/Caches/localstack/volume
  • Linux: ~/.cache/localstack/volume
  • Windows: %LOCALAPPDATA%/localstack/cache/volume

Host mode

When LocalStack is running in host mode, the system directories /usr/lib/localstack or /var/lib/localstack are not used. Instead, the root directory is changed to FILESYSTEM_ROOT which defaults to ./.filesystem, i.e. the LocalStack project root.