ENV Url

Env-composable service urls complete with key overrides as to facilitate maximum flexibility and to simplify integration with kubernetes.

Env mapping behaviors

ENV
{PREFIX}_URL	set service url, disregarding other overrides
{PREFIX}_URL_ENV	override {PREFIX}_URL env mapping
{PREFIX}_SCHEME	set url scheme component
{PREFIX}_SCHEME_ENV	override {PREFIX}_SCHEME env mapping
{PREFIX}_HOST	set url host component
{PREFIX}_HOST_ENV	override {PREFIX}_HOST env mapping
{PREFIX}_PATH	set url path component
{PREFIX}_PATH_ENV	override {PREFIX}_PATH env mapping
{PREFIX}_QUERY	set url query component
{PREFIX}_QUERY_ENV	override {PREFIX}_QUERY env mapping
{PREFIX}_USERINFO	set url userinfo component
{PREFIX}_USERINFO_ENV	override {PREFIX}_USERINFO env mapping

Example

use env_url::*;

#[derive(EnvURL)]
#[env_url(env_prefix = "REDIS", default = "redis://127.0.0.1:6379")]
pub struct RedisDB;

let service_url = RedisDB::service_url();

Kubernetes usage

As kubernetes can set services to env variables for service discovery, it's very useful to be able to override the env mappings like so

REDIS_HOST_ENV: STAGE_REDIS_MASTER_PORT_6379_TCP_ADDR
REDIS_PORT_ENV: STAGE_REDIS_MASTER_SERVICE_PORT_REDIS