--- title: "Read/write NAS local files (LocalFs.x)" slug: "readwrite-nas-local-files-localfs" status: "update" updated: 2026-03-09T15:33:08Z published: 2026-03-09T15:33:10Z canonical: "support.lusid.com/readwrite-nas-local-files-localfs" --- > ## Documentation Index > Fetch the complete documentation index at: https://support.lusid.com/llms.txt > Use this file to discover all available pages before exploring further. # Read/write NAS local files (LocalFs.x) You can request `LocalFs.*` providers from FINBOURNE and host them locally to interact with files on a network share (via a NAS or similar device). Providing you have a suitable license and access control permissions, you can: - Read from CSV, Excel, SQLite, XML, Parquet and plain text files stored locally, perhaps in preparation for loading investment data into LUSID. - Write to files of the same types, perhaps having retrieved investment data from LUSID. - Search folders for files. ## Hosting the `LocalFs.*` providers 1. Make sure your computer has .NET 8 installed. 2. As a LUSID user with the `lusid-administrator` role, navigate to `https://<your-domain>.lusid.com/honeycomb/swagger/index.html`, where `<your-domain>` is the root of your LUSID domain, for example `acmecorp`. If you do not have the `lusid-adminstrator` role, [see the appendix](/v1/docs/readwrite-nas-local-files-localfs#appendix-a-allowing-nonadministrative-users-to-downloading-binaries). 3. Use Swagger's **Try it out** button for the `DownloadBinary` API to request the `LocalFileSystem_Providers` binary: ![](https://cdn.document360.io/d575ad81-c0ed-4980-bbd1-d59ac5c3de82/Images/Documentation/825cc4a1-4b5b-4c96-8fe8-268559a5f6fb.png) 4. Click the **Download file** link in the response to download the binary to your browser's download location: ![](https://cdn.document360.io/d575ad81-c0ed-4980-bbd1-d59ac5c3de82/Images/Documentation/483d26a9-f4fa-47eb-8b86-5b16b0585265.png) 5. Navigate to the download and run the following install command, omitting the `.nupkg` file extension and, on Mac, using the x64 version of `dotnet`: ```powershell C:\Users\JohnDoe\Download> dotnet tool install Finbourne.Luminesce.LocalFs -g --add-source "." ``` The service is installed in the following location: - Windows: `%USERPROFILE%\.dotnet\tools\.store\` - Linux/MacOS: `$HOME/.dotnet/tools/.store/` 6. Run the following command to start the service (omitting the `.exe` extension on Linux or MacOS): ```powershell C:\Users\JohnDoe\.dotnet\tools> luminesce-local-file-access.exe --quiet --authClientDomain= --certificateFallback=DownloadMayMint ``` ...where `<your-domain>` is the root of your LUSID domain, for example `--authClientDomain=acmecorp`. Note the `DownloadMayMint` option mints a new certificate if you do not have one already; more information on managing certificates is coming soon. > **Note**: For information on all the command line options, run the command `luminesce-local-file-access.exe --help`. 7. Open your [LUSID web app](https://www.lusid.com/app/home), navigate to the **Data Virtualisation > Query Editor** window, and click the **Refresh** button (highlighted in red). You should be able to search for `LocalFs` providers: ![](https://cdn.document360.io/d575ad81-c0ed-4980-bbd1-d59ac5c3de82/Images/Documentation/ae41f6ab-a1cf-4a84-a64c-9220d167d60b.png) To stop the service, enter `Ctrl-C` in the terminal window. The providers should disappear from your web app catalog. To uninstall the package, perhaps in order to upgrade to a newer version, run the command `dotnet tool uninstall Finbourne.Luminesce.LocalFs -g`. ## Renaming the `LocalFs.*` providers You can optionally rename or remove the `Mine` suffix for all providers (you cannot change the `LocalFs.*` prefix). To do this, open the `<install-location>\.dotnet\tools\.store\finbourne.luminesce.localfs\<version>\finbourne.luminesce.localfs\<version>\tools\net8.0\any\api-settings.json` file and search for the following line: ```sql "ProviderNameFormat": "{0}.Mine", ``` Change the text after `{0}` to something more intuitive or memorable, or remove it altogether, for example: ```sql "ProviderNameFormat": "{0}", ``` The new names are reflected in the Luminesce catalog the next time you sign in. Note you must restart the service if you change this file while it is running. ## Understanding access control permissions for the `LocalFs.*` providers You and any other LUSID user wishing to run queries against a `LocalFs.*` provider must have suitable access control permissions. The general principle of creating policies for Luminesce providers, assigning them to roles and roles to users, is explained [in this article](/v1/docs/creating-policies-to-control-access-to-providers-for-different-luminesce-end-users). Note you should automatically have sufficient privileges if you are the LUSID domain owner with the built-in `lusid-administrator` role. ## Getting help for the `LocalFs.*` providers You can access the latest online help for `LocalFs.*` providers by running a query like this: ```sql @x = use LocalFs.Csv.Mine --help enduse; ``` ## Using the `LocalFs.*` providers The `LocalFs.*` providers are very similar to the `Drive.*` providers for interacting with files in Drive, except you must provide either an absolute location, or a location relative to that of the `luminesce-local-file-access.exe` file. For reading data using the `LocalFs.Csv.Mine`, `LocalFs.Excel.Mine`, `LocalFs.Sqlite.Mine`, `LocalFs.Xml.Mine`, `LocalFs.RawText.Mine` and `LocalFs.Parquet.Mine` providers, specify a full path using the `--file` option, for example: ```sql @x = use LocalFs.Csv.Mine --file=C:\Users\JohnDoe\instruments.csv   # Either an absolute file path... --file=..\..\instruments.csv              # ...or one relative to luminesce-local-file-access.exe enduse; select * from @x ``` For writing data using the `LocalFs.SaveAs.Mine` provider, specify a folder path using the `--path` option and the names of one file per input table using the `--fileNames` option, for example: ```sql @data1 = select distinct TableName from Sys.Field order by 1; @data2 = select distinct TableName, FieldName from Sys.Field order by 1,2; @x = use LocalFs.SaveAs.Mine with @data1, @data2 --path=C:\Users\JohnDoe --fileNames file1 file2 enduse; select * from @x ``` For finding files using the `LocalFs.File.Mine` provider, specify the `RootPath` parameter to nominate a base folder in the `where` clause of your query, for example: ```sql select * from LocalFs.File.Mine where RootPath = 'C:\Users\JohnDoe' and Name like '%.csv' and IncludeSubdirectories = True ``` For lists of options and examples of other operations, see the documentation for the similar `Drive.*` providers below: | **To interact with...** | **Read from using the ... provider** (links are to docs for similar `Drive.*` providers) | **Write to using the ... provider** (links are to docs for similar `Drive.*` providers) | | --- | --- | --- | | CSV and similarly-structured files | `LocalFs.Csv.Mine` --> [Drive.Csv](/v1/docs/drivecsv) | `LocalFs.SaveAs.Mine` --> [Drive.SaveAs](/v1/docs/drivesaveas) | | Excel files | `LocalFs.Excel.Mine` --> [Drive.Excel](/v1/docs/driveexcel) | | SQlite files | `LocalFs.Sqlite.Mine` --> [Drive.Sqlite](/v1/docs/drivesqlite) | | XML files | `LocalFs.Xml.Mine` --> [Drive.Xml](/v1/docs/drivexml) | | Text files | `LocalFs.RawText.Mine` --> [Drive.RawText](/v1/docs/driverawtext) | | Apache Parquet files | `LocalFs.Parquet.Mine` --> [Drive.Parquet](/v1/docs/driveparquet) | | Find files | `LocalFs.File.Mine` --> [Drive.File](/v1/docs/drivefile) | N/A | ## Appendix A: Allowing non-administrative users to downloading binaries Once a license is granted, users with the `lusid-administrator` role have permission to download the `LocalFileSystem_Providers` binary out-of-the-box. To enable less privileged users to download, [create a feature policy](/v1/docs/how-do-i-create-a-feature-policy) consisting of the following JSON, assign it to a role, and the role to their LUSID user: ```json {    "description": "User can download LocalFS binary",    "applications": [        "Honeycomb"    ],    "grant": "Allow",    "selectors": [        {            "idSelectorDefinition": {                "identifier": {                    "code": "LocalFileSystem_Providers",                    "scope": "Honeycomb"                },                "actions": [                    {                        "scope": "Honeycomb",                        "activity": "DownloadBinary",                        "entity": "Feature"                    }                ],                "name": "Local file system binary",                "description": "User can download LocalFS binary"            }        }    ],    "when": {        "activate": "2023-01-01T00:00:00.0000000+00:00",        "deactivate": "9999-12-31T23:59:59.9999999+00:00"    } } ```