Step Flow
Step flow manager for Elixir applications
Generated documentation
Usage
Add AMQP as a dependency in your mix.exs
file.
def deps do
[
{:step_flow, "~> 0.1.0"}
]
end
and add into extra applications:
def application do
[
mod: {MyApplication.Application, []},
extra_applications: [
:step_flow
]
]
end
Configurations to start
Postgres configuration
Add into configuration files:
config :step_flow, Ecto.Repo,
hostname: "localhost",
username: "postgres",
password: "postgres",
database: "step_flow_dev",
runtime_pool_size: 10
it can also be used with environment variables:
config :step_flow, Ecto.Repo,
hostname: {:system, "DATABASE_HOSTNAME"},
username: {:system, "DATABASE_USERNAME"},
password: {:system, "DATABASE_PASSWORD"},
database: {:system, "DATABASE_NAME"},
runtime_pool_size: {:system, "DATABASE_POOL_SIZE"}
RabbitMQ configuration
Add into configuration files:
config :step_flow, StepFlow.Amqp,
hostname: "localhost",
port: 5672,
username: "guest",
password: "guest",
virtual_host: ""
it can also be used with environment variables:
config :step_flow, StepFlow.Amqp,
hostname: {:system, "RABBITMQ_HOSTNAME"},
port: {:system, "RABBITMQ_PORT"},
username: {:system, "RABBITMQ_USERNAME"},
password: {:system, "RABBITMQ_PASSWORD"},
virtual_host: {:system, "RABBITMQ_VIRTUAL_HOST"},
Slack integration (optional)
Configuring the Slack integration enable notification to Slack channel. It's used to:
- send notification when job is in error
- send a notification via a Step
To enable integration, update configuration files:
config :step_flow, StepFlow,
exposed_domain_name: {:system, "EXPOSED_DOMAIN_NAME"},
slack_api_token: {:system, "SLACK_API_TOKEN"},
slack_api_channel: {:system, "SLACK_API_CHANNEL"}
Remarks: the slack_api_channel
configure the channel for error jobs notification.
The message contains also a link to the workflow, so exposed_domain_name
configure the hostname of the hosted application.
Expose StepFlow Rest API
Step Flow provides the Rest API to mamage Workflows and Jobs.
Create a module with:
defmodule MyApplicationWeb.StepFlow.Plug do
@moduledoc false
use StepFlow.Plug
end
Then in Phoenix router redirect the API part to the module:
defmodule MyApplicationWeb.Router do
use MyApplicationWeb, :router
pipeline :api do
plug(:accepts, ["json"])
end
scope "/api", MyApplicationWeb do
pipe_through(:api)
scope "/step_flow", StepFlow do
forward("/", Plug)
end
# add other routes here
end
end
To enable authentication checks over Step Flow API configure callbacks in configuration:
config :step_flow, StepFlow,
authorize: [
module: MyApplicationWeb.Authorize,
get_jobs: [:user_check, :right_technician_check],
get_workflows: [:user_check, :right_technician_check],
post_workflows: [:user_check, :right_technician_check],
put_workflows: [:user_check, :right_technician_check],
delete_workflows: [:user_check, :right_technician_check],
post_workflows_events: [:user_check, :right_technician_check],
get_definitions: [:user_check, :right_technician_check],
post_worker_definitions: [:user_check, :right_technician_check],
get_worker_definitions: [:user_check, :right_technician_check],
get_workflows_statistics: [:user_check]
]
Enable StepFlow live notification to WebSocket
StepFlow can be configured to send messages on job updates (to enable refresh of UI via WebSocket for example). To broadcast messages, the application endpoint needs to be configured.
config :step_flow, StepFlow,
endpoint: MyApplicationWeb.Endpoint
Configuration of the default working directory for workers
Each workers works with big data files, mostly on shared storage. The default access point need to be configured using:
config :step_flow, StepFlow,
workers_work_directory: "/data/mount/point"