How to pack a hooks-based charm with Charmcraft¶

Introduced in Charmcraft 1.4

See first: Ops | Turn a hooks-based charm into an ops charm

Suppose you have a legacy hooks-only charm, for example, tiny-bash, which you can clone with:

git clone https://github.com/erik78se/tiny-bash

To make it packable by Charmcraft, all you need to do is navigate inside the charm directory and create a charmcraft.yaml file with the part definition for a hooks-based charm, as shown below:

type: charm

bases:
  - build-on:
    - name: "ubuntu"
      channel: "20.04"
    run-on:
    - name: "ubuntu"
      channel: "20.04"

parts:
  tiny-bash:
    plugin: dump
    source: .
    prime:
      - LICENSE
      - README.md
      - config.yaml
      - copyright
      - hooks
      - icon.svg
      - metadata.yaml

After this, you can pack your charm with charmcraft pack, as usual:

charmcraft pack

If successful, the result should look like the following.

user@host:~$

Charms packed:

>     tiny-bash_ubuntu-20.04-amd64.charm

The charm file should contain all the files listed in the prime section of the tiny-bash part and the charm manifest.

unzip -l tiny-bash_ubuntu-20.04-amd64.charm

user@host:~$

Archive:  tiny-bash_ubuntu-20.04-amd64.charm

>   Length      Date    Time    Name

> ---------  ---------- -----   ----

>       423  2021-11-12 19:37   metadata.yaml

>       431  2021-11-12 19:37   README.md

>        12  2021-11-12 19:37   config.yaml

>      3693  2021-11-12 19:37   icon.svg

>        38  2021-11-12 19:37   copyright

>       261  2021-11-12 20:08   manifest.yaml

>     34523  2021-11-12 19:37   LICENSE

>       381  2021-11-12 19:37   hooks/update-status

>       346  2021-11-12 19:37   hooks/start

>      1294  2021-11-12 19:37   hooks/shared-fs-relation-changed

>       563  2021-11-12 19:37   hooks/stop

>       497  2021-11-12 19:37   hooks/leader-elected

>       447  2021-11-12 19:37   hooks/install

>       417  2021-11-12 19:37   hooks/leader-settings-changed

>       811  2021-11-12 19:37   hooks/upgrade-charm

>       625  2021-11-12 19:37   hooks/config-changed

> ---------                     -------

>     44762                     16 files

And you can also deploy your application with juju deploy, as usual:

juju deploy ./tiny-bash_ubuntu-20.04-amd64.charm

user@host:~$

Located local charm "tiny-bash", revision 0

> Deploying "tiny-bash" from local charm "tiny-bash", revision 0

If successful, the result should look as below, i.e., with the application status active.

juju status

user@host:~$

Model    Controller           Cloud/Region         Version  SLA          Timestamp

> default  localhost-localhost  localhost/localhost  2.9.12   unsupported  17:23:23-03:00

App        Version  Status  Scale  Charm      Store  Channel  Rev  OS      Message
tiny-bash           active      1  tiny-bash  local             0  ubuntu  update-status ran: 20:22

Unit          Workload  Agent  Machine  Public address  Ports  Message
tiny-bash/0*  active    idle   0        10.2.17.31             update-status ran: 20:22

Machine  State    DNS         Inst id        Series  AZ  Message
0        started  10.2.17.31  juju-55481c-0  focal       Running