everettcaleb/snowflake

package main

import (
    "time"

    "github.com/everettcaleb/envconfig"
)

type snowflakeEnvConfig struct {
    BasePath             string `env:"APP_BASE_PATH"`
    Epoch                uint64 `env:"SNOWFLAKE_EPOCH"`
    Port                 int    `env:"PORT"`
    RedisURI             string `env:"REDIS_URI" required:"true"`
    RedisMachineIDPrefix string `env:"REDIS_MACHINE_ID_PREFIX"`
    UseMilliseconds      bool   `env:"SNOWFLAKE_USE_MILLISECONDS"`
}

func defaultConfig(epoch time.Time) *snowflakeEnvConfig {
    return &snowflakeEnvConfig{
        BasePath:             "/",
        Epoch:                uint64(epoch.Unix()),
        Port:                 8080,
        RedisMachineIDPrefix: "snowflake:machine:",
        RedisURI:             "redis://localhost:6379",
        UseMilliseconds:      false,
    }
}

func loadEnvConfig() (*snowflakeEnvConfig, error) {
    // Parse the default epoch
    epoch, err := time.Parse(time.RFC3339, "2016-01-01T00:00:00Z")
    if err != nil {
        return nil, err
    }

    // Set the defaults
    config := defaultConfig(epoch)

    // Load from the environment
    err = envconfig.Unmarshal(config)
    if err != nil {
        return nil, err
    }
    return config, nil
}