# Env Var Overrides

Every [Config Setting](https://cfconfig.ortusbooks.com/the-basics/config-items) can be overridden by convention by creating environment variables in the shell where you run `box`. This is ideal for Docker containers or CI builds where you want to easily set one-off settings and not require an entire JSON file. You can set these as actual environment variables or [Java system properties of the CLI](https://commandbox.ortusbooks.com/usage/execution#ad-hoc-java-properties-for-the-cli). Env vars are loaded AFTER any `.cfconfig.json` files have been loaded by convention and will override any settings in the JSON. They are not case-sensitive.

The variable must start with the text `cfconfig_` and will be followed by the name of the setting.

```bash
cfconfig_adminPassword=myPass
```

For nested settings inside a struct or array, you can use underscores to represent dots. Note the following will error if there is not already a datasource named `myDSN` in the server.

```bash
cfconfig_datasources_myDSN_password=myPass
```

The overrides are applied using the same mechanism that the `cfconfig set` command uses, which means you can also pass JSON directly for complex values.

```bash
# JSON which will be parsed
cfconfig_mailServers=[{"port":"25","smtp":"localhost2"}]
```

On OS's like Windows which allow for any manner of special characters, you can provide any string which would also be valid for the `config set` command. Ex:

```bash
# dot-delimited keys
cfconfig_datasources.myDSN.password=myPass
# array indexes too
cfconfig_mailServers[1].smtp=mail.server.com
```

When you provide JSON, the `append` flag will be set to true when adding the configuration to what's already in CommandBox.

Overridden env vars will **not** be written to any `.cfconfig.json` file and will be lost when box stops. They will also take precedence and override any explicit settings already set.

## Target a Lucee/Railo specific server/web context

If you want to specify a setting via an env var that targets a web context, you can use the following conventions:

```bash
# Default (server context)
cfconfig_requestTimeout=...

# Force web context.  (On adobe, just loaded normally)
cfconfig_web_requestTimeout=...

# Force server context- same as default. (On adobe, just loaded normally)
cfconfig_server_requestTimeout=...
```