DevExtreme Angular - Custom Sources

You can use the CustomStore component to configure access to a custom data source. DevExtreme provides ASP.NET and PHP extensions to configure it and implement server-side data processing. You can also use a third-party extension for MongoDB.

To access a server that uses another technology, configure the CustomStore manually. In this case, data can be processed on the client or server. In the former case, switch the CustomStore to the raw mode and load all data from the server in the load function as shown in the following example:

jQuery
JavaScript
$(function() {
    $("#sankeyContainer").dxSankey({
        dataSource: new DevExpress.data.DataSource({
            store: new DevExpress.data.CustomStore({
                loadMode: "raw",   
                load: function () {
                    return $.getJSON('https://mydomain.com/MyDataService');
                }
            }), 
            paginate: false
        })
    });
});
Angular
TypeScript
HTML
import { ..., Inject } from "@angular/core";
import { HttpClient, HttpClientModule } from "@angular/common/http";
import { DxSankeyModule } from "devextreme-angular";
import DataSource from "devextreme/data/data_source";
import CustomStore from "devextreme/data/custom_store";
import "rxjs/add/operator/toPromise";
// ...
export class AppComponent {
    sankeyDataSource: any = {};
    constructor(@Inject(HttpClient) httpClient: HttpClient) {
        this.sankeyDataSource = new DataSource({
            store: new CustomStore({
                loadMode: "raw",   
                load: () => {
                    return httpClient.get('http://mydomain.com/MyDataService')
                        .toPromise();
                }
            }),
            paginate: false
        });
    }
}
@NgModule({
    imports: [
        // ...
        DxSankeyModule,
        HttpClientModule
    ],
    // ...
})
<dx-sankey ...
    [dataSource]="sankeyDataSource">
</dx-sankey>
Vue
<template>
    <DxSankey ... 
        :data-source="dataSource" />
</template>
<script>
import { DxSankey } from "devextreme-vue/sankey";
import CustomStore from "devextreme/data/custom_store";
import DataSource from "devextreme/data/data_source";
// ...
function handleErrors(response) {
    if (!response.ok)
        throw Error(response.statusText);
    return response;
}
const sankeyDataSource = new DataSource({
    store: new CustomStore({
        loadMode: "raw",   
        load: () => {
            return fetch("https://mydomain.com/MyDataService")
                    .then(handleErrors);
        }
    }),
    paginate: false
});
export default {
    // ...
    data() {
        return {
            dataSource: sankeyDataSource
        };
    },
    components: {
        // ...
        DxSankey
    }
}
</script>
React
import React from "react";
import Sankey from "devextreme-react/sankey";
import CustomStore from "devextreme/data/custom_store";
import DataSource from "devextreme/data/data_source";
// ...
function handleErrors(response) {
    if (!response.ok)
        throw Error(response.statusText);
    return response;
}
const sankeyDataSource = new DataSource({
    store: new CustomStore({
        loadMode: "raw",   
        load: () => {
            return fetch("https://mydomain.com/MyDataService")
                    .then(handleErrors);
        }
    }),
    paginate: false
});
class App extends React.Component {
    render() {
        return (
            <Sankey ...
                dataSource={sankeyDataSource}>
            </Sankey>
        );
    }
}
export default App;

In the latter case, use the CustomStore's load function to send data processing settings to the server. These settings are passed as a parameter to the load function and depend on the operations (filtering, sorting, and others) you enabled in the DataSource. The following settings apply to the Sankey:

After receiving these settings, the server should apply them to data and send back an object with the following structure:

{
    data: [ ... ] // result data objects
}

The following example shows how to make a query for data:

jQuery
JavaScript
$(function() {
    $("#sankeyContainer").dxSankey({
        dataSource: new DevExpress.data.DataSource({
            store: new DevExpress.data.CustomStore({
                load: function(loadOptions) {
                    var d = $.Deferred(),
                        params = {};
                    [
                        "sort", 
                        "filter", 
                        "searchExpr", 
                        "searchOperation", 
                        "searchValue"
                    ].forEach(function(i) {
                        if(i in loadOptions && isNotEmpty(loadOptions[i])) 
                            params[i] = JSON.stringify(loadOptions[i]);
                    });
                    $.getJSON("http://mydomain.com/MyDataService", params)
                        .done(function(result) {
                            // Here, you can perform operations unsupported by the server
                            // or any other operations on the retrieved data
                            d.resolve(result.data);
                        });
                    return d.promise();
                }
            }),
            paginate: false
        })
    });
});
function isNotEmpty(value) {
    return value !== undefined && value !== null && value !== "";
}
Angular
TypeScript
HTML
import { ..., Inject } from "@angular/core";
import { HttpClient, HttpClientModule, HttpParams } from "@angular/common/http";
import { DxSankeyModule } from "devextreme-angular";
import DataSource from "devextreme/data/data_source";
import CustomStore from "devextreme/data/custom_store";
import "rxjs/add/operator/toPromise";
// ...
export class AppComponent {
    sankeyDataSource: any = {};
    constructor(@Inject(HttpClient) httpClient: HttpClient) {
        function isNotEmpty(value: any): boolean {
            return value !== undefined && value !== null && value !== "";
        }
        this.sankeyDataSource = new DataSource({
            store: new CustomStore({
                load: (loadOptions) => {
                    let params: HttpParams = new HttpParams();
                    [
                        "sort", 
                        "filter", 
                        "searchExpr", 
                        "searchOperation", 
                        "searchValue"
                    ].forEach(function(i) {
                        if(i in loadOptions && isNotEmpty(loadOptions[i])) 
                            params = params.set(i, JSON.stringify(loadOptions[i]));
                    });
                    return httpClient.get("http://mydomain.com/MyDataService", { params: params })
                        .toPromise()
                        .then(result => {
                            // Here, you can perform operations unsupported by the server
                            // or any other operations on the retrieved data
                            return result.data;
                        });
                }
            }),
            paginate: false
        });
    }
}
@NgModule({
    imports: [
        // ...
        DxSankeyModule,
        HttpClientModule
    ],
    // ...
})
<dx-sankey ...
    [dataSource]="sankeyDataSource">
</dx-sankey>
Vue
<template>
    <DxSankey ... 
        :data-source="dataSource" />
</template>
<script>
import DxSankey from "devextreme-vue/sankey";
import CustomStore from "devextreme/data/custom_store";
import DataSource from "devextreme/data/data_source";
// ...
function isNotEmpty(value) {
    return value !== undefined && value !== null && value !== "";
}
function handleErrors(response) {
    if (!response.ok)
        throw Error(response.statusText);
    return response;
}
const sankeyDataSource = new DataSource({
    store: new CustomStore({
        load: (loadOptions) => {
            let params = "?";
            [
                "sort", 
                "filter", 
                "searchExpr", 
                "searchOperation", 
                "searchValue"
            ].forEach(function(i) {
                if(i in loadOptions && isNotEmpty(loadOptions[i])) 
                    params += `${i}=${JSON.stringify(loadOptions[i])}&`;
            });
            params = params.slice(0, -1);
            return fetch(`https://mydomain.com/MyDataService${params}`)
                .then(handleErrors)
                .then(response => response.json())
                .then((result) => {
                    // Here, you can perform operations unsupported by the server
                    // or any other operations on the retrieved data
                    return result.data;
                });
        }
    }),
    paginate: false
});
export default {
    // ...
    data() {
        return {
            dataSource: sankeyDataSource
        };
    },
    components: {
        // ...
        DxSankey
    }
}
</script>
React
import React from "react";
import Sankey from "devextreme-react/sankey";
import CustomStore from "devextreme/data/custom_store";
import DataSource from "devextreme/data/data_source";
// ...
function isNotEmpty(value) {
    return value !== undefined && value !== null && value !== "";
}
function handleErrors(response) {
    if (!response.ok) 
        throw Error(response.statusText);
    return response;
}
const sankeyDataSource = new DataSource({
    store: new CustomStore({
        load: (loadOptions) => {
            let params = "?";
            [
                "sort", 
                "filter", 
                "searchExpr", 
                "searchOperation", 
                "searchValue"
            ].forEach(function(i) {
                if(i in loadOptions && isNotEmpty(loadOptions[i])) 
                    params += `${i}=${JSON.stringify(loadOptions[i])}&`;
            });
            params = params.slice(0, -1);
            return fetch(`https://mydomain.com/MyDataService${params}`)
                .then(handleErrors)
                .then(response => response.json())
                .then((result) => {
                    // Here, you can perform operations unsupported by the server
                    // or any other operations on the retrieved data
                    return result.data;
                });
        }
    }),
    paginate: false
});
class App extends React.Component {
    render() {
        return (
            <Sankey ...
                dataSource={sankeyDataSource}>
            </Sankey>
        );
    }
}
export default App;
See Also