18F/e-QIP-prototype

package env

import (
    "fmt"
    "net/url"
    "os"
    "strconv"
    "strings"

    "github.com/18F/e-QIP-prototype/api"
)

// Native settings using environment variables.
type Native struct{}

// Configure the environment.
func (env Native) Configure() {
    // Setting DatabaseURI overwrites all of the other database environment variables.
    if env.Has(api.DatabaseURI) {

        // Parse the address as a URI. If it fails behave as if DatabaseURI is not set
        dbString := env.String(api.DatabaseURI)
        uri, err := url.Parse(dbString)
        if err != nil {
            fmt.Printf("ERROR: The %s did not parse: %s\n", api.DatabaseURI, dbString)
        } else {
            // Remove the leading slash on the path to retrieve the database name
            dbName := strings.TrimPrefix(uri.Path, "/")

            // Ignore whether the password was set or not since an empty string suffices
            // for the connection options as well.
            dbPassword, _ := uri.User.Password()

            if env.Has(api.DatabaseUser) || env.Has(api.DatabasePassword) ||
                env.Has(api.DatabaseHost) || env.Has(api.DatabaseName) {
                fmt.Printf("WARNING: Setting %s is overwriting the values set in %s, %s, %s, and %s.\n",
                    api.DatabaseURI, api.DatabaseUser, api.DatabasePassword, api.DatabaseHost, api.DatabaseName)
            }

            os.Setenv(api.DatabaseUser, uri.User.Username())
            os.Setenv(api.DatabasePassword, dbPassword)
            os.Setenv(api.DatabaseHost, uri.Host)
            os.Setenv(api.DatabaseName, dbName)
        }
    }

    // ensure the db variable defaults are set
    env.ensure(api.DatabaseUser, "postgres")
    env.ensure(api.DatabaseHost, "localhost:5432")
    env.ensure(api.DatabaseName, "postgres")
    env.ensure(api.TestDatabaseName, "eapp_test")

    env.ensure(api.GolangEnv, "development")
    env.ensure(api.LogLevel, "warning")
    env.ensure(api.SessionTimeout, "15")
    env.ensure(api.Port, "3000")
    env.ensure(api.HashRouting, "0")
    env.ensure(api.FlushStorage, "0")
    env.ensure(api.BasicEnabled, "0")
    env.ensure(api.SamlEnabled, "0")
    env.ensure(api.AttachmentsEnabled, "1")
    env.ensure(api.FileMaximumSize, "5000000")
    env.ensure(api.FileTypes, ".tiff;.png;.pdf")
    env.ensure(api.WsEnabled, "1")
    env.ensure(api.DevDisableSSL, "0")
}

// Has returns true if the environment has a value for the given environment variable.
func (env Native) Has(name string) bool {
    if os.Getenv(name) == "" {
        return false
    }
    return true
}

// String returns the string value of the given environment variable.
func (env Native) String(name string) string {
    return os.Getenv(name)
}

// True returns the boolean value of the given environment variable.
func (env Native) True(name string) bool {
    b, err := strconv.ParseBool(os.Getenv(name))
    if err != nil {
        return false
    }
    return b
}

// Int returns the integer value of the given environment variable.
func (env Native) Int(name string) int {
    i, err := strconv.Atoi(os.Getenv(name))
    if err != nil {
        return 0
    }
    return i
}

func (env Native) ensure(name, value string) {
    if !env.Has(name) {
        os.Setenv(name, value)
    }
}