Add docs on api key environment variables

docs/create-packages/Symbol-Packages-snupkg.md

@@ -73,6 +73,10 @@ The [`SymbolPackageFormat`](/dotnet/core/tools/csproj#symbolpackageformat) prope
     nuget SetApiKey Your-API-Key
     ```
 
+    > [!TIP]
+    > Starting with NuGet 7.6, you can set the `NUGET_API_KEY` and `NUGET_SYMBOL_API_KEY` environment variables instead of using `SetApiKey`.
+    > For more information, see [environment variables](../reference/cli-reference/cli-ref-environment-variables.md).
+
 1. After publishing your primary package to nuget.org, push the symbol package as follows.
 
     ```cli

docs/quickstart/includes/publish-dotnet.md

@@ -4,6 +4,10 @@ From the folder that contains the *.nupkg* file, run the following command. Repl
 dotnet nuget push <package-file> --api-key <API-key> --source https://api.nuget.org/v3/index.json
 ```
 
+> [!TIP]
+> Starting with NuGet 7.6 (.NET SDK 10.0.300), you can set the `NUGET_API_KEY` environment variable instead of passing `--api-key` on the command line.
+> This is useful in CI/CD scenarios where you don't want to pass the key as a command-line argument.
+
 The output shows the results of the publishing process:
 
 ```output

docs/reference/cli-reference/cli-ref-environment-variables.md

@@ -37,5 +37,7 @@ The list of properties documented in [NuGet pack and restore as MSBuild targets]
 | NUGET_XMLDOC_MODE | Determines how assemblies XML documentation file extraction should be handled. | Supported modes are *skip* (do not extract XML documentation files), *compress* (store XML doc files as a zip archive) or *none* (default, treat XML doc files as regular files). |
 | NUGET_CERT_REVOCATION_MODE | Determines how the revocation status check of the certificate used to sign a package, is performed when a signed package is installed or restored. When not set, defaults to `online`.| Possible values *online* (default), *offline*.  Related to [NU3028](../errors-and-warnings/NU3028.md) |
 | NUGET_ENHANCED_MAX_NETWORK_TRY_COUNT | Configures the maximum number of times an HTTP connection should be retried when enhanced retries are enabled. | A number representing how many retries to perform, the default value is `6`. |
+| NUGET_API_KEY | The API key used to authenticate when pushing packages. If not set, the value from the `apikeys` section of `NuGet.Config` is used. | Available in NuGet 7.6 and higher. The command-line option takes precedence over this environment variable. |
+| NUGET_SYMBOL_API_KEY | The API key used to authenticate when pushing symbol packages. If not set, the value from the `apikeys` section of `NuGet.Config` is used. | Available in NuGet 7.6 and higher. The command-line option takes precedence over this environment variable. |
 | NUGET_ENHANCED_NETWORK_RETRY_DELAY_MILLISECONDS | Configures the amount of time to wait in milliseconds before retrying an HTTP connection when enhanced retries are enabled. | Number of millseconds to wait, the default value is `1000`. |
 

docs/reference/cli-reference/cli-ref-push.md

@@ -33,7 +33,7 @@ where `<packagePath>` identifies the package to push to the server.
 
 - **`-ApiKey`**
 
-  The API key for the target repository. If not present,  the one specified in the config file is used.
+  The API key for the target repository. If not present, the `NUGET_API_KEY` environment variable is read *(7.6+)*. If neither is set, the one specified in the config file is used.
 
 - **`-ConfigFile`**
 
@@ -77,7 +77,7 @@ where `<packagePath>` identifies the package to push to the server.
 
 - **`-SymbolApiKey`**
 
-  *(3.5+)* Specifies the API key for the URL specified in `-SymbolSource`.
+  *(3.5+)* Specifies the API key for the URL specified in `-SymbolSource`. If not present, the `NUGET_SYMBOL_API_KEY` environment variable is read *(7.6+)*. If neither is set, the one specified in the config file is used.
 
 - **`-Timeout`**
 

docs/reference/cli-reference/cli-ref-setapikey.md

@@ -13,6 +13,10 @@ ms.topic: reference
 
 Saves an API key for a given server URL into `NuGet.Config` so that it doesn't need to be entered for subsequent push commands.
 
+> [!TIP]
+> Starting with NuGet 7.6, you can also set the `NUGET_API_KEY` environment variable to provide an API key for push operations without storing it in `NuGet.Config`.
+> For more information, see [environment variables](cli-ref-environment-variables.md).
+
 ## Usage
 
 ```cli

docs/reference/nuget-config-file.md

@@ -252,6 +252,10 @@ When using unencrypted passwords:
 
 Stores keys for sources that use API key authentication, as set with the [`nuget setapikey` command](../reference/cli-reference/cli-ref-setapikey.md).
 
+> [!NOTE]
+> Starting with NuGet 7.6, the `NUGET_API_KEY` and `NUGET_SYMBOL_API_KEY` environment variables can also provide API keys for push operations.
+> The command-line option takes precedence over the environment variable, and the environment variable takes precedence over keys stored in `NuGet.Config`.
+
 | Key | Value |
 | --- | --- |
 | (source URL) | The encrypted API key. |