rockcraft.yaml¶
A Rockcraft project is defined in a YAML file named rockcraft.yaml
at the root of the project tree in the filesystem.
This Reference section is for when you need to know which options can be
used, and how, in this rockcraft.yaml file.
Format specification¶
name¶
Type: string
Required: Yes
The name of the rock. This value must conform with Pebble’s format for layer
files, meaning that the name:
must start with a lowercase letter [a-z];
must contain only lowercase letters [a-z], numbers [0-9] or hyphens;
must not end with a hyphen, and must not contain two or more consecutive hyphens.
title¶
Type: string
Required: No
The human-readable title of the rock. If omitted, defaults to name.
summary¶
Type: string
Required: Yes
A short summary describing the rock.
description¶
Type: string
Required: Yes
A longer, possibly multi-line description of the rock.
version¶
Type: string
Required: Yes
The rock version, used to tag the OCI image and name the rock file.
base¶
Type: One of ubuntu@20.04 | ubuntu@22.04 | ubuntu@24.04 | bare
Required: Yes
The base system image that the rock’s contents will be layered on. This is also
the system that will be mounted and made available when using Overlays. The
special value bare means that the rock will have no base system at all,
which is typically used with static binaries or
Chisel slices.
Note
The notation “ubuntu:<channel>” is also supported for some channels, but this format is deprecated and should be avoided.
Note
Base ubuntu@24.04 is still unstable and under active development. To use
it, build-base must be devel.
build-base¶
Type: One of ubuntu@20.04 | ubuntu@22.04 | devel
Required: Yes, if base is bare
The system and version that will be used during the rock’s build, but not
included in the final rock itself. It comprises the set of tools and libraries
that Rockcraft will use when building the rock’s contents. This field is
mandatory if base is bare, but otherwise it is optional and defaults to
the value of base.
Note
The notation “ubuntu:<channel>” is also supported for some channels, but this format is deprecated and should be avoided.
Note
devel is a “special” value that means “the next Ubuntu version, currently
in development”. This means that the contents of this system changes
frequently and should not be relied on for production rocks.
license¶
Type: string, in SPDX format
Required: Yes
The license of the software packaged inside the rock. This must match the SPDX
format, but is case insensitive (e.g. both MIT and mit are valid).
run-user¶
Type: string
Required: No
The default OCI user. It must be a supported shared user. Currently, the only supported shared user is “_daemon_” (with UID/GID 584792). It defaults to “root” (with UID 0).
environment¶
Type: dict
Required: No
A set of key-value pairs specifying the environment variables to be added to the base image’s OCI environment.
Note
String interpolation is not yet supported so any attempts to dynamically
define environment variables with $ will end in a project
validation error.
services¶
Type: dict, following the Pebble Layer Specification format
Required: No
A list of services for the Pebble entrypoint. It uses Pebble’s layer
specification syntax exactly, with each entry defining a Pebble service. For
each service, the override and command fields are mandatory, but all
others are optional.
entrypoint-service¶
Type: string
Required: No
The optional name of the Pebble service to serve as the OCI entrypoint. If set,
this makes Rockcraft extend ["/bin/pebble", "enter", "--verbose"] with
["--args", "<serviceName>"]. The command of the Pebble service must
contain an optional argument that will become the OCI CMD.
Warning
This option must only be used in cases where the targeted deployment environment has unalterable assumptions about the container image’s entrypoint.
checks¶
Type: dict, following the Pebble Layer Specification format
Required: No
A list of health checks that can be configured to restart Pebble services
when they fail. It uses Pebble’s layer specification syntax, with each
entry corresponding to a check. Each check can be one of three types:
http, tcp or exec.
platforms¶
Type: dict
Required: Yes
The set of architecture-specific rocks to be built. Supported architectures are:
amd64, arm64, armhf, i386, ppc64el, riscv64 and s390x.
Entries in the platforms dict can be free-form strings, or the name of a
supported architecture (in Debian format).
Warning
All target architectures must be compatible with the architecture of the host where Rockcraft is being executed (i.e. emulation is not supported at the moment).
platforms.<entry>.build-on¶
Type: list[string]
Required: Yes, if build-for is specified or if <entry> is not a
supported architecture name.
Host architectures where the rock can be built. Defaults to <entry> if that
is a valid, supported architecture name.
platforms.<entry>.build-for¶
Type: string | list[string]
Required: Yes, if <entry> is not a supported architecture name.
Target architecture the rock will be built for. Defaults to <entry> that
is a valid, supported architecture name.
Note
At the moment Rockcraft will only build for a single architecture, so
if provided build-for must be a single string or a list with exactly one
element.
parts¶
Type: dict
Required: Yes
The set of parts that compose the rock’s contents (see Parts).
Note
The fields entrypoint, cmd and env are not supported in
Rockcraft. All rocks have Pebble as their entrypoint, and thus you must use
services to define your container application.
extensions¶
Type: list[string]
Required: No
Extensions to enable when building the ROCK.
Currently supported extensions:
flask-framework
Example¶
name: hello
title: Hello World
summary: An Hello World rock
description: |
This is just an example of a Rockcraft project
for a Hello World rock.
version: latest
base: bare
build-base: [email protected]
license: Apache-2.0
run-user: _daemon_
environment:
FOO: bar
services:
hello:
override: replace
command: /usr/bin/hello -t
environment:
VAR1: value
VAR2: "other value"
platforms:
amd64:
armhf:
build-on: ["armhf", "arm64"]
ibm:
build-on: ["s390x"]
build-for: s390x
parts:
hello:
plugin: nil
stage-packages:
- hello