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Update README to clarify HCL, INI, and Java Properties support moved to plugin #2098

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Update README to clarify HCL, INI, and Java Properties support moved to plugin #2098

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Add Upgrade and Breaking changes to the readme by pointing
nook24 Dec 24, 2025
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#2092 Update README to use GitHubs Info blockquote
nook24 Dec 24, 2025
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33 changes: 25 additions & 8 deletions README.md
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Expand Up @@ -42,7 +42,8 @@ Many Go projects are built using Viper including:
go get github.com/spf13/viper
```

> **NOTE** Viper uses [Go Modules](https://go.dev/wiki/Modules) to manage dependencies.
> [!NOTE]
> Viper uses [Go Modules](https://go.dev/wiki/Modules) to manage dependencies.


## Why use Viper?
Expand Down Expand Up @@ -81,7 +82,8 @@ Viper uses the following precedence for merging:
* external key/value stores
* defaults

> **NOTE** Viper configuration keys are case insensitive.
> [!NOTE]
> Viper configuration keys are case insensitive.

### Reading Config Files

Expand All @@ -90,9 +92,10 @@ Viper requires minimal configuration to load config files. Viper currently suppo
* JSON
* TOML
* YAML
* INI
* envfile
* Java Propeties
* HCL ([see](UPGRADE.md#breaking-hcl-java-properties-ini-removed-from-core))
* INI ([see](UPGRADE.md#breaking-hcl-java-properties-ini-removed-from-core))
* Java Properties ([see](UPGRADE.md#breaking-hcl-java-properties-ini-removed-from-core))

A single Viper instance only supports a single configuration file, but multiple
paths may be searched for one.
Expand Down Expand Up @@ -136,11 +139,20 @@ if err := viper.ReadInConfig(); err != nil {

// Config file found and successfully parsed
```

> **NOTE (since 1.6)** You can also have a file without an extension and
> [!NOTE]
> **Since 1.6:** You can also have a file without an extension and
> specify the format programmatically, which is useful for files that naturally
> have no extension (e.g., `.bashrc`).

> [!NOTE]
> **Since 1.20:** In order to reduce third-party dependencies, Viper dropped support for the following formats from the core:
> - HCL
> - INI
> - Java properties
>
> You can still use these formats though by importing them from [github.com/go-viper/encoding](https://github.com/go-viper/encoding).
> See the [migration guide](UPGRADE.md#breaking-hcl-java-properties-ini-removed-from-core) for more details.

### Writing Config Files

At times you may want to store all configuration modifications made during run
Expand Down Expand Up @@ -246,7 +258,8 @@ viper.GetBool("verbose") // true

Viper has full support for environment variables.

> **NOTE** Unlike other configuration sources, environment variables are case
> [!NOTE]
> Unlike other configuration sources, environment variables are case
> sensitive.

```go
Expand Down Expand Up @@ -526,7 +539,8 @@ GetString("datastore.metric.host") // "127.0.0.1"
GetInt("host.ports.1") // 6029
```

> **NOTE** Viper _does not_ deep merge configuration values. Complex values
> [!NOTE]
> Viper _does not_ deep merge configuration values. Complex values
> that are overridden will be entirely replaced.

If there exists a key that matches the delimited key path, its value will be
Expand Down Expand Up @@ -765,6 +779,9 @@ the `sync` package). Concurrent reads and writes can cause a panic.

See [TROUBLESHOOTING.md](TROUBLESHOOTING.md).

## Upgrade an breaking changes

For details on updates and breaking changes in new Viper releases, please refer to [UPGRADE.md](UPGRADE.md).

## Development

Expand Down