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  1. API reference
  2. Welcome
    1. Component overview
    2. Get Flexmonster
    3. Quick start
    4. System requirements
    5. Troubleshooting
    6. Managing license keys
    7. Migrating from WebDataRocks to Flexmonster
  3. Integration with frameworks
    1. Available tutorials
    2. Integration with Angular
    3. Integration with React
    4. Integration with Vue
    5. Other integrations
      1. Integration with Python
        1. Integration with Django
        2. Integration with Jupyter Notebook
      2. Integration with React Native
      3. Integration with AngularJS (v1.x)
      4. Integration with TypeScript
      5. Integration with R Shiny
      6. Integration with jQuery
      7. Integration with Ionic
      8. Integration with Electron.js
      9. Integration with Webpack
      10. Integration with RequireJS
  4. Connecting to Data Source
    1. Supported data sources
    2. JSON
      1. Connecting to JSON
      2. Connecting to JSON using Flexmonster Data Server
      3. Data types in JSON
    3. CSV
      1. Connecting to CSV
      2. Connecting to CSV using Flexmonster Data Server
      3. Data types in CSV
    4. Database
      1. Connecting to SQL databases
      2. Connecting to a MySQL database
      3. Connecting to a Microsoft SQL Server database
      4. Connecting to a PostgreSQL database
      5. Connecting to an Oracle database
      6. Connecting to other databases
    5. Flexmonster Data Server
      1. Getting started with Flexmonster Data Server
      2. Installation guide
      3. Configurations reference
      4. Data sources guide
      5. Security and authorization guide
      6. The Data Server as a DLL
        1. Getting started with the Data Server as a DLL
        2. Referring the Data Server as a DLL
        3. Implementing the API controller
        4. Implementing the server filter
        5. Implementing the custom parser
        6. DLL configurations reference
        7. The controller's methods for request handling
    6. MongoDB
      1. Introduction to Flexmonster MongoDB Connector
      2. Getting started with the MongoDB Connector
      3. Embedding the MongoDB Connector into the server
    7. Microsoft Analysis Services
      1. Connecting to Microsoft Analysis Services
      2. Getting started with Flexmonster Accelerator
      3. Referring the Accelerator as a DLL
      4. Configuring the authentication process
      5. Configuring a secure HTTPS connection
      6. Troubleshooting
    8. Custom data source API
      1. Introduction to the custom data source API
      2. A quick overview of a sample Node.js server
      3. A quick overview of a sample .NET Core server
      4. Implement your own server
        1. Implementing the custom data source API server
        2. Implementing filters
        3. Supporting more aggregation functions
        4. Returning data for the drill-through view
    9. Elasticsearch
      1. Connecting to Elasticsearch
      2. Configuring the mapping
    10. Pentaho Mondrian
      1. Connecting to Pentaho Mondrian
      2. Getting started with the Accelerator
      3. Configuring Mondrian roles
      4. Configuring username/password protection
      5. Configuring a secure HTTPS connection
      6. Troubleshooting
  5. Security
    1. Security in Flexmonster
    2. Security aspects of connecting to an OLAP cube
      1. Ways of connecting to an OLAP cube
      2. The data transfer process
      3. Data security
      4. Data access management
  6. Configuring report
    1. What is a report
    2. Data source
    3. Slice
    4. Options
    5. Mapping
    6. Number formatting
    7. Conditional formatting
    8. Set the report for the component
    9. Get the report from the component
    10. Date and time formatting
    11. Configuring global options
    12. Export and print
    13. Calculated values
    14. Custom sorting
  7. Charts
    1. Available tutorials
    2. Flexmonster Pivot Charts
    3. Integration with Highcharts
    4. Integration with amCharts
    5. Integration with Google Charts
    6. Integration with FusionCharts
    7. Integration with any charting library
  8. Customizing
    1. Customizing the Toolbar
    2. Customizing appearance
    3. Customizing the context menu
    4. Customizing the grid
    5. Customizing the pivot charts
    6. Localizing the component
  9. Updating to the latest version
    1. Updating to the latest version
    2. Release notes
    3. Migration guide from 2.7 to 2.8
    4. Migration guide from 2.6 to 2.7
    5. Migration guide from 2.5 to 2.6
    6. Migration guide from 2.4 to 2.5
    7. Migration guide from 2.3 to 2.4
    8. Migration guide from 2.2 to 2.3
    9. Documentation for older versions
  10. Flexmonster CLI Reference
    1. Overview
    2. Troubleshooting the CLI
    3. flexmonster create
    4. flexmonster add
    5. flexmonster update
    6. flexmonster version
    7. flexmonster help
Table of contents

Implementing the server filter

When there is a need to show a certain subset of data on the grid depending on a user’s role, the server filter can be used. It allows filtering the data right on the application’s back end, so Flexmonster Pivot receives and shows only the part of the data that meets filtering conditions.

In this guide, we describe the concept of the server filter, its structure, and the example of the server filter implementation:

The general idea of the server filter

The main advantage of the server filter is that it can be used as a data access management tool. Using the server filter, Flexmonster.DataServer.Core.dll will filter the data based on the user role received from Flexmonster Pivot.

Here is one of the possible server-side filtering implementations:

  1. When Flexmonster Pivot sends a request for data to the server, the user’s role can be included in the request headers with customizeAPIRequest. This method allows editing the headers before the request is sent to the server.
  2. After the Data Server accepts the request, the request headers can be read. Depending on the received role, the DLL can apply the appropriate filter to the data.
  3. The resulting subset of data is sent to Flexmonster Pivot. The component gets the dataset specific to the current user.

To see how the server filter can be implemented, refer to the example section.

Example of a server filter

To make the server filter’s implementation easier, we designed a sample ASP.NET Core application using Flexmonster.DataServer.Core.dll. This application contains an example of a server filter, which can be viewed in the FlexmonsterAPIController.cs file.

To create a new ASP.NET Core application with the Data Server or embed the DLL in the existing project, refer to the guide on Flexmonster.DataServer.Core.dll.

Defining user roles on the server side

In the sample, the data is filtered based on the user’s region token sent by the component via request headers. A special dictionary defines which subset of data should correlate to the received token. The dictionary contains all possible region tokens and field members corresponding to them:

private static Dictionary<string, List<object>> _userPermissions =
new Dictionary<string, List<object>>()
{
/* a user with the "AdminToken" token will see
the report on all the countries */
{"AdminToken", null },

/* a user with the "EuropeToken" token will see
details about Germany and France */
{"EuropeToken", new List(){ "Germany","France" } },

/* a user with the "AmericaToken" token will see
highlights about USA and Canada */
{"AmericaToken", new List(){ "USA","Canada" } },

/* a user with the "AustraliaToken" token will see
info about Australia */
{"AustraliaToken", new List(){ "Australia" } },
};

Defining the server filter

In the sample project, the server filter is defined in a separate function. First, a user token is read from the request headers, and then, depending on that token, the filter is applied:

private ServerFilter GetServerFilter()
{
// get the user token from the request headers
HttpContext.Request.Headers.TryGetValue("UserToken", out StringValues userRole);
if (userRole.Count == 1)
{
// create a server filter
ServerFilter serverFilter = new ServerFilter();
// specify a field to filter
serverFilter.Field = new Field() {
UniqueName = "Country",
Type = ColumnType.stringType
};
// include the members that correspond to the user token
serverFilter.Include = _userPermissions[userRole[0]];
return serverFilter;
}
return null;
}

To learn more about the server filter’s parameters and their types, see the server filter structure

Applying the server filter

After the filter is specified, it is passed as a parameter to GetMembers() and GetAggregatedData() methods, for example:

public MembersResponse PostMembers([FromBody]MembersRequest request)
{
var response = _apiService.GetMembers(request, GetServerFilter());
return new JsonResult(response);
}

The server filter structure

The server filter has the following structure:

public class ServerFilter
{
public Field Field { get; set; }
public List<object> Include { get; set; }
public List<object> Exclude { get; set; }
}

Below is a detailed description of the filter parameters:

  • Field – Field. A field to filter. If a non-existent field is specified, Flexmonster.DataServer.Core.dll throws the exception.
  • Include – List<object>. Field members to include in the server’s response.
  • Exclude – List<object>. Field members to exclude from the server’s response.

Here is an example of how the server filter can be created:

ServerFilter serverFilter = new ServerFilter();
serverFilter.Field = new Field() {
UniqueName = "Country",
Type = ColumnType.stringType
};
serverFilter.Include = new List<object>(){ "USA", "Canada" };

What’s next?

You may be interested in the following articles: