cdist-type__single_binary_service(7)¶

NAME¶

cdist-type__single_binary_service - Setup a single-binary service

DESCRIPTION¶

This type is designed to easily deploy and configure a single-binary service named ${__object_id}.

A good example of this are Prometheus exporters.

This type makes certain assumptions that might not be correct on your system. If you need more flexibility, please get in touch and provide a use-case (and hopefully a backwards-compatible patch).

This type will place the downloaded binary and, if requested, other extra binaries in /usr/local/bin.

If a –config-file-source is provided, it will be placed under: /etc/${__object_id}.conf.

This type supports services managed by __runit(7) when systemd is not the init system being used.

REQUIRED PARAMETERS¶

checksum: This will be passed verbatim to __download(7). Use something like sha256:….
url: This will be passed verbatim to __download(7).
version: This type will use a thumbstone file with a “version” number to track whether or not a service must be updated. This thumbstone file is placed under /usr/local/bin/.${__object_id}.cdist.version.

BOOLEAN PARAMETERS¶

unpack: If present, the contents of –url will be treated as an archive to be unpacked with __unpack(7). See also –unpack-args and –extra-binary.
do-not-manage-user: Always considered present when –user is root. If present, the user in –user will not be managed by this type with __user, this means it must exist beforehand when installing the service and it will not be removed by this type.

OPTIONAL PARAMETERS¶

config-file-source: If present, this file’s contents will be placed under /etc/${__object_id}.conf with permissions 0440 and ownership assigned to –user and –group. If - is passed, this type’s stdin will be used.
user: The user under which the service will run. Defaults to root. If this user is not root and –do-not-manage-user is not present, this user will be created or removed as per the –state parameter.
user-home-dir: Does not have an effect if –do-not-manage-user is used or –user is root. The home directory of the service user. It will be created. Defaults to /nonexistent, in this case the home directory will not be created.
group: The group under which the service will run. Defaults to –user.
state: Whether the service is to be present (default) or absent. When absent, this type will clean any binaries listed in –extra-binary and also the config file as described in –config-file-source.
binary: This will be the binary name. Defaults to ${__object_id}. If –unpack is used, a binary with this name must be unpacked. Otherwise, the contents of –url will be placed under this binary name.
env: An env file consiting of ENVIRONMENT_VARIABLE=VALUE, one variable per line. Empty lines and those starting with # are ignored.
service-args: Any extra arguments to pass along with –service-exec. Beware that any service-args having the format –config=/etc/foo.cfg should be represented in the following way –service-exec=’–config=/etc/foo.cfg’
service-exec: The executable to use for this service. Defaults to /usr/local/bin/BINARY_NAME where BINARY_NAME is the resulting value of –binary.
service-definition: The service definition to be used as an override. Note that this type decides dinammically between runit and systemd, and you can currently only define either a systemd unit or a runit script here. Use this parameter only for testing and get in touch to discuss how your particular use-case can be supported by the type.
service-description: The service description to be used in, e.g. the systemd unit file. Defaults to cdist-managed ‘${__object_id}’ service.
unpack-args: Only has an effect if –unpack is used. These arguments will be passed verbatim to __unpack(7). Very useful as this type assumes the archive does not have the binaries in subdirectories; that can be worked around with –unpack-args ‘–tar-strip 1’.
unpack-extension: Only has an effect if –unpack is used. The file extension of the file to unpack, defaults to .tar.gz.
working-directory: If set, the working directory with which the service will be started.

OPTIONAL MULTIPLE PARAMETERS¶

extra-binary: Only useful with –unpack. If passed, these binaries will also be installed when –state is present and removed when –state is absent. Handle with care :-).

EXAMPLES¶

# Install and enable the ipmi_exporter service
#   The variables are defined in the manifest previously
__single_binary_service ipmi_exporter \
        --user "${USER}" \
        --service-args ' --config.file=/etc/ipmi_exporter.conf' \
        --version "${SHOULD_VERSION}" \
        --checksum "${CHECKSUM}" \
        --url "${DOWNLOAD_URL}" \
        --state "present" \
        --unpack \
        --unpack-args "--tar-strip 1" \
        --config-file-source '-' <<-EOF
# Remotely managed, changes will be lost
# [...] config contents goes here
EOF

# Remove the ipmi_exporter service along with the user and its config
__single_binary_service ipmi_exporter \
        --user "${USER}" \
        --version "${SHOULD_VERSION}" \
        --checksum "${CHECKSUM}" \
        --url "${DOWNLOAD_URL}" \
        --state "absent"

# Same, but the service was using my user! Let's not delete that!
__single_binary_service ipmi_exporter \
        --user "evilham" \
        --do-not-manage-user \
        --version "${SHOULD_VERSION}" \
        --checksum "${CHECKSUM}" \
        --url "${DOWNLOAD_URL}" \
        --state "absent"

AUTHORS¶

Evilham <contact@evilham.com>