Ams Push Server

The ams push server is a component that handles the push functionality for the respective push enabled subscriptions in the argo-messaging-service.

Prerequisites

Before you start, you need to issue a valid certificate.

Set Up

1. Install Golang 1.14

2. Create a new work space:

   mkdir ~/go-workspace

   export GOPATH=~/go-workspace

   export PATH=$PATH:$GOPATH/bin

   You may add the export lines into the ~/.bashrc, /.zshrc or the ~/.bash_profile file to have GOPATH environment variable properly setup upon every login.

3. Get the latest version

   go get github.com/ARGOeu/ams-push-server

4. Get dependencies(If you plan on contributing to the project else skip this step):

   Ams-push-server uses the dep tool for dependency handling.

   • Install the dep tool. You can find instructions depending on your platform at Dep.

5. To build the service use the following command:

   go build

6. To run the service use the following command:

   ./ams-push-server (This assumes that there is a valid configuration file at /etc/ams-push-server/conf.d/ams-push-server-config.json).

   Else

   ./ams-push-server --config /path/to/a/json/config/file

7. To run the unit-tests:

   Inside the project's folder issue the command:

   go test $(go list ./... | grep -v /vendor/)

Configuration

The service depends on a configuration file in order to be able to run.This file contains the following information:

{
 "service_port": 9000,
 "certificate": "/path/cert.pem",
 "certificate_key": "/path/certkey.pem",
 "certificate_authorities_dir": "/path/to/cas",
 "ams_token": "sometoken",
 "ams_host": "localhost",
 "ams_port": 8080,
 "verify_ssl": true,
 "tls_enabled": true,
 "trust_unknown_cas": false,
 "log_level": "INFO",
 "skip_subs_load": false,
 "acl": ["OU=my.local,O=mkcert development certificate"],
 "syslog_enabled": false
}

• service_port: The port that the service will bind to.

• certificate: The certificate file which the service will use.

• certificate_key: The key to the respective certificate

• certificate_authroties_dir: Directory containing .pem files that the service will use in order to build the trusted CA pool. The CA pool will be used to validate the certificates from incoming client requests.

• ams_token: THe argo messaging token that the service will use in order to communicate with ams.NOTE that the token MUST correspond to a push worker user in ams.

• ams_host: The ams http endpoint.

• ams_port: The ams http endpoint port.

• verify_ssl: Whether or not it should verify the various https endpoint it targets.

• tls_enabled: Enable or disable tls support between client and server

• trust_unknown_cas: Whether or not the service should accept certificates from CAs not found in its trusted CA pool. (Mainly used for development purposes)

• log_level: DEBUG,INFO,WARNING,ERROR

• skip_subs_load: The service will try by default to contact the ams in order to retrieve all active push subscriptions
  that are assigned to it and start their push cycles(consume->send->ack). This will be done through the its user profile in ams(which is the profile associated with the) ams_token). You can control this behavior and decide whether or not to pre-load any already active subscriptions.

• acl: List of certificate DNs which are allowed to access the service.

• syslog_enabled: Direct logging of the service to the syslog socket

You can find the configuration template at conf/ams-push-server-config.template.

Managing the protocol buffers and gRPC definitions

In order to modify any .proto file you will need the following

• Read on how to install the protoc compiler on your platform here.

• Install the go plugin. go get -u github.com/golang/protobuf/protoc-gen-go

• install the go gRPC package. go get -u google.golang.org/grpc

• Inside api/<version>/grpc compile. protoc -I proto/ proto/ams.proto --go_out=plugins=grpc:proto