Go Config

Go Config is a simple package that allows to load basic data for a Golang application. It supports toml, json, yaml or xml file or content to instantiate environment variables.

1. Config

Before to run application you may setup a supportedconfig.toml with Config values. Check out the following tables to know all Config parameters detailed.

Parameter	Description	Type	Default	Required
environment	Website environment.	string		NO
service	Website service identifier as string.	string		NO
[server]	Http server config data.	Server		YES
[token]	Token data config data.	Token		NO
[mongodb]	Postgres database config data.	Database		NO
[mysql]	MySql database config data.	Database		NO
[postgres]	Postgres database config data.	Database		NO
[audit]	Auditing options config data.	ExternalService		NO
[jaeger]	Jaeger tracing options config data.	ExternalService		NO
[loki]	Grafana Loki options config data.	ExternalService		NO
[tempo]	Tempo tracer config data.	ExternalService		NO
[prometheus]	Prometheus monitoring config data.	ExternalService		NO
[redis]	Redis cache config data.	ExternalService		NO
[ai_agent]	AI agent configuration with model and provider description.	AIAgent		NO
[settings] (1)	Holds mapped key-value attributes. Allows an undefined number of new attributes.	map[string]string		NO

⁽¹⁾ Settings is not available to xml loader.

1.1. Server type

Parameter	Description	Type	Default	Required
host	HTTP server host name.	string		YES
port	HTTP server port number.	int		YES
allowed_origins	Allowed hosts to CORS allowance.	[]string		NO

1.2. Database type

To set up [mysql] and [postgres] use the following parameters:

Parameter	Description	Type	Default	Required
db	Database name.	string		YES
host	Database host.	string		YES
migrations_path	Migrations directory path.	string	file://migrations/<mongo><mysql><postgres>	NO
password	Database password.	string		YES
port	Database port.	int	3306, 5432, 27017 (2)	YES
user	Database user with needed privileges over database.	string		YES

⁽²⁾ 3306 for MySQL, 5432 for Postgres and 27017 for MongoDB.

1.3. Token type

Parameter	Description	Type	Default	Required
secret	Website token secret string.	string		YES
max_age	Maximum duration of a token (in seconds).	int	86400	NO

1.4. AI Agent

Parameter	Description	Type	Default	Required
provider	AI agent provider identification name or description.	string		NO
host	AI agent host address.	string		NO
token	Authorization token to AI agent.	string		NO
model	AI model identification.	string		NO

1.5. External Service type

Parameter	Description	Type	Default	Required
Enable	Enable flag to activate tracing.	bool	FALSE	NO
Host	Service host address.	string	(3)	NO
Token	Service token string.	string		NO

⁽³⁾ Host default values are specified in External Host Default Values table.

1.4.1. External Host Default Values

For ExternalService main config, the Host default value depends on the main service, and those values are described in the next table.

Service	Default Host Value
Audit
Jaeger	http://localhost:14268/api/traces
Loki	http://localhost:3100/loki/api/v1/push
Prometheus
Tempo	http://localhost:4318/v1/traces
Redis	localhost:6379

2. Load data

First you need to get dependency go_config dependency by calling go get, with the wanted release.

go get github.com/ribeirohugo/go_config@latest

2.1. Environment

OS environment data can be loaded by calling Load method. It will load config variables from environment.

os.SetVar("SERVER_HOST", "localhost")

cfg, err := toml.Load()
if err != nil {
    log.Fatal(err)
}

Variables and subvariables uses the following logic:

ENVIRONMENT = "TEST"

SERVER_HOST = "localhost"

MONGODB_USER = "username"

It will return a config.Config struct variable or an error, if anything unexpected occurs.

2.2. Toml

Data can be loaded using toml package, by calling Load method. It supports a config.toml file properly fulfilled.

configFile := "config.toml"

cfg, err := env.Load(configFile)
if err != nil {
    log.Fatal(err)
}

It will return a config.Config struct variable or an error, if anything unexpected occurs.

2.3. YAML

yaml data can be loaded, by calling Load method, with a config.yaml file properly fulfilled.

configFile := "config.yaml"

cfg, err := yaml.Load(configFile)
if err != nil {
    log.Fatal(err)
}

It will return a config.Config struct variable or an error, if anything unexpected occurs.

2.4. JSON

json data can be loaded, by calling Load method, with a config.json file properly fulfilled.

configFile := "config.json"

cfg, err := json.Load(configFile)
if err != nil {
    log.Fatal(err)
}

It will return a config.Config struct variable or an error, if anything unexpected occurs.

2.5. XML

xml data can be loaded, by calling Load method, with a config.xml file properly fulfilled.

configFile := "config.xml"

cfg, err := xml.Load(configFile)
if err != nil {
    log.Fatal(err)
}

It will return a config.Config struct variable or an error, if anything unexpected occurs.

2.6. Dotenv

dotenv data can be loaded, by calling Load method, with a .env file properly fulfilled.

configFile := ".env"

cfg, err := dotenv.Load(configFile)
if err != nil {
    log.Fatal(err)
}

It will return a config.Config struct variable or an error, if anything unexpected occurs.