The titan Endpoint Provider

The endpoint provider is used by the request/response brick pair to dynamically provide REST endpoints for flow inletts to the outside world.

Building/ running

To run the service simply use go run ./cmd/endpointprovider

or to create an executable file go build ./cmd/endpointprovider

It features the following command line arguments:

Name	Options (default)	Purpose
port	(9020)	Port on which the REST Api serves
zmq-port	(9021)	Port on which the ZeroMQ router can be reached
zmq-bind	(*)	IP or interface to bind the ZeroMQ router to
service-id	("no default set")	Service ID string used for authentication
user-manager	localhost:9000"	URL of the user service
flow-manager	localhost:9002"	URL of the flow manager
log-level	info/debug/warning/error	Log level
	(info)
log-to-kafka	(false)	Flag: use kafka hook for logging
kafka	(10.14.0.23:9092)	host:port of kafka broker
service-topic	(titan.servicelogs)	kafka topic for logs
config-file	(internal/app/endpointprovider/config.yaml)	Configuration file

Generally, all settings listed above can be done also via environment variables, whereby the variables are composed of a prefix (TITAN_EP) and the argument using snake case:

TITAN_EP_ARGUMENT, e.g. TITAN_EP_LOG_LEVEL

Usage

Register an endpoint

Send a registration with a zmq dealer to the zmq host:port to subscribe for an endpoint.

if the structure of the registration object is

Name	Type	Doc
Token	string	optional token string
FlowUID	string	UUID of the flow
FlowName	string	name of the flow
BrickName	string	name of the brick in the flow

The endpoint will be : host:port/UserName_of_FlowOwner/FlowName/BrickName

Alternatively, the structure of the registration object can be

Name	Type	Doc
Token	string	optional token string
Endpoint	string	the endpoint to register

The endpoint will be : host:port/Endpoint

All requests to the endpoint will be send to the subscriber as Response object

Name	Type	Doc
RequestID	string	UUID of the request
Request	Request	request

a Request object contains

Name	Type	Doc
Header	map	request header map (string-> variant)
Method	string	UUID of the request
Body	variant	request body

If the endpoint is registered to include authentication with a token all requests need to include a header:

Key	Value
Authorization	token

Delete an endpoint

send stop request to zmq endpoint via dealer

"stop":"endpoint"

further requests to the endpoint will not be possible.

Send a response to an endpoint

To send a response send a response message to the zmq host:port with a zmq dealer containing

Name	Type	Doc
RequestID	string	UUID of the request
Status	int	Status code
Body	variant	a response body
Response	string	a response type ("TEXT" or "JSON"), default: "JSON"