Worker

The djinn-worker is the component that handles executing builds that are submitted via the server or the scheduler. You may need to install some additional dependencies on the worker machine depending on the drivers you want to make available.

External Dependencies
Driver Dependencies
Configuring the Worker
Running the Worker
Configuring the Worker Daemon

External Dependencies

Detailed below are the software dependencies that the worker needs in order to start and run,

DEPENDENCY	REASON
PostgreSQL	Primary data store for the server.
Redis	Data store used as the build queue.
SMTP Server	Used for sending emails on build failures.

Driver Dependencies

Detailed below are the software dependencies that the worker needs in order to execute a build via that driver.

DRIVER	SOFTWARE
`docker`	The `dockerd` process for managing containers.
`qemu`	The `qemu` software package for creating virtual machines.

Configuring the worker

Worker parameters

NAME	TYPE	DESCRIPTION
`parallelism`	`int`	The parallelism to use when running multiple builds at once. Set to `0` to use the number of CPU cores available.
`driver`	`string`	The driver that will be used for executing builds on the worker.
`crypto`	`object`	Configuration settings for generating names for artifacts.
`crypto.block`	`string`	The block key used for encrypting data. This must be either 16, 24, or 32 characters in length.
`crypto.salt`	`string`	Salt the is used to generate secret.
`database`	`object`	Provides connection information to the PostgreSQL database.
`database.addr`	`string`	The address of the PostgreSQL server to connect to.
`database.name`	`string`	The name of the database to use.
`database.username`	`string`	The name of the database user.
`database.password`	`string`	The password of the database user.
`database.tls`	`object`	TLS configuration for connecting via TLS.
`database.tls.ca`	`string`	Path to the CA root to use.
`database.tls.cert`	`string`	Path to the certificate to use.
`database.tls.key`	`string`	Path to the key to use.
`redis`	`object`	Providers connection information to the Redis database.
`redis.addr`	`string`	The address of the Redis server to connect to.
`redis.password`	`string`	The password used if the Redis server is password protected.
`smtp`	`object`	Provides connection innformation to an SMTP server for sending emails.
`smtp.addr`	`string`	The address of the SMTP server.
`smtp.ca`	`string`	The path to the root CA if connecting via TLS.
`admin`	`string`	The email address to be used in the `From` field of emails that are sent.
`username`	`string`	The username for authentication.
`pasword`	`string`	The password for authentication.
`store label`	`object`	Configuration parameters for each of the file stores the server uses. The `label` will be the store type, one of: `artifacts` `images` `objects` there must be a store configuration block for each.
`store.type`	`string`	The type of the store to use. Must be `file`.
`store.path`	`string`	The location where the files are.
`store.limit`	`int`	The maximum size of files being stored. Set to `0` for no limit.
`provider label`	`object`	Configuration parameters for reach third-party provider you want to integrate with, where the `label` is the name of that provider. As of now, only `github`, and `gitlab` are supported.

Note: The worker does not need the client_id or client_secret details of a provider. For example, provider github {} will suffice for GitHub integration.

EXAMPLE


pidfile "/var/run/djinn/worker.pid"

log info "/var/log/djinn/worker.log"

parallelism 0

driver "qemu"

timeout "30m"

provider github {}
provider gitlab {}

crypto {
    block "1a2b3c4d5e6f7g8h"
    salt  "1a2b3c4d5e6f7g8h"
}

database {
    addr "localhost:5432"
    name "djinn"

    username "djinn_worker"
    password "secret"
}

redis {
    addr "localhost:6379"
}

smtp {
    addr "smtp.example.com:587"

    ca "/etc/ssl/cert.pem"

    admin "no-reply@djinn-ci.com"

    username "postmaster@example.com"
    password "secret"
}

store artifacts {
    type  "file"
    path  "/var/lib/djinn/artifacts"
    limit 52428800
}

store images {
    type "file"
    path "/var/lib/djinn/images"
}

store objects {
    type "file"
    path "/var/lib/djinn/objects"
}

Running the Worker

To run the worker simply invoke the djinn-worker binary. There are two flags that can be given to the djinn-worker binary.

-config - This specifies the configuration file to use, by default this will be djinn-worker.conf.
-driver - This specifies the driver configuration file to use, for configuring the drivers you want to support on your server, by default this will be djinn-driver.conf.

Configuring the Worker Daemon

The dist directory contains files for running the Djinn Worker as a daemon on Linux systems that use systemd and SysVinit for daemon management. Use whichever suits your needs, and modify accordingly.