@map-colonies/csw-client

CSW-CLIENT

This package provides client-side API for OGC CSW service(s) written in TypeScript.

Suits for Node.JS and React/Angular applications

Package boilerplate based on ts-npm-package-boilerplate

This Client library is based on Jsonix and ogc-schemas libraries.

Code samples are provided by TypeScript.

Installation

Install package by NPM

npm install @map-colonies/csw-client --save

Install package by YARN

yarn add @map-colonies/csw-client --save

!!! IMPORTANT: Apply integrated PATCHES

Add following script to your package.json

"scripts": {
  .
  .
  .
  "patch:deps": "cd ./node_modules/@map-colonies/csw-client && patch-package --patch-dir ./dist/patches"
}

You can add patch:deps script to one of the npm hooks or run it manually.

For example add it to postinstall hook:

"scripts": {
  "postinstall": "yarn run patch:deps && <your_own_postinstall>",
  .
  .
  .
  "patch:deps": "cd ./node_modules/@map-colonies/csw-client && patch-package --patch-dir ./dist/patches"
}

Usage

// import CswClient class 
import { CswClient, ICapabilities } from from '@map-colonies/csw-client';

// later in code
const csw = new CswClient('<YOUR_OGC_CSW_SRV_URL>', <YOUR_REQUEST_EXECUTOR_FUNC>, <CONFIG>);
// trigger one of the exposed methods
csw.GetDomain('<propertyName>').then((data: ICapabilities) => {
  // your code
}); 

Implemented operations/methods

Client library instantiation

• Instantiation - new

    // import CswClient class 
    import { CswClient } from from '@map-colonies/csw-client';
    import Axios, { Method } from 'axios';
  
    // import desired ADDITIONAL schemas
    const ISO19139_GCO_20060504 = require('ogc-schemas').ISO19139_GCO_20060504;
    const ISO19139_GMD_20060504 = require('ogc-schemas').ISO19139_GMD_20060504;
    const GML_3_2_0 = require('ogc-schemas').GML_3_2_0;
  
    // define your own requestExecutor
    const myRequest = async (url: string, method: string, params: Record<string, unknown>): Promise<any> => {
      const errorMsg = 'CLIENT HTTP ERROR BY AXIOS';
      return Axios.request({
        url,
        method: method as Method,
        ...params,
      })
        .then((res) => res)
        .catch((error) => {
          console.error(errorMsg);
          throw error;
        });
    };
  
    // later in code
    const cswConfig = {
      schemas: [
        GML_3_2_0,
        ISO19139_GCO_20060504,
        ISO19139_GMD_20060504,
      ],
      nameSpaces: {
        namespacePrefixes: { // define ADDITIONAL namespace prefixes
          'http://schema.mapcolonies.com': 'mc',
          'http://www.isotc211.org/2005/gmd': 'gmd',
          'http://www.isotc211.org/2005/gco': 'gco',
        },
      },
      credentials: {},
    };
    const csw = new CswClient('http://127.0.0.1:56477/?version=2.0.2&service=CSW', myRequest, cswConfig);
  

Basic OWS operations

• GetCapabilities(): Promise

  Allow clients to retrieve information describing the service instance

    csw.GetCapabilities().then((data: ICapabilities) => {
      ... // your code
    });
  

• DescribeRecord(): Promise

  Allows a client to discover elements of the information model supported by the target catalog service

    csw.DescribeRecord().then((data) => {
      ... // your code
    });
  

CSW queries

• GetDomain(propertyName: string): Promise

  Obtain runtime information about the range of values of a metadata record element or request parameter.

    csw.GetDomain('title').then((data) => {
      ... // your code
    });
  

• GetRecords(start: number, max: number, opts: { filter?: IFilterField[]; sort?: ISortField[] }, outputSchema: string): Promise

  Get metadata records according to defined filter and sort order

   const options = {
     filter: [
       {
         field: 'mcgc:geojson',
         bbox: {
           llat: 31.90,
           llon: 36.80,
           ulat: 31.91,
           ulon: 36.81,
         },
       },
       {
         field: 'mcgc:name',
         like: 'magic_place',
       },
     ],
     sort: [
       {
         field: 'mcgc:name',
         desc: false,
       },
       {
         field: 'mcgc:creation_date',
         desc: true,
       },
  
     ]
   };
   csw.GetRecords(1, 10, options, 'http://schema.myschema.com').then((data) => {
     ... // your code
   });
  

• GetRecordsById(id_list: string[]): Promise

  Get metadata records by ID list

   csw.GetRecordsById(['1', '2', '5']).then((data) => {
     ... // your code
   });
  

CSW CRUD operations

• InsertRecords(records: any[]): Promise

  Create catalog records

   csw.InsertRecords(records).then((data) => {
     ... // your code
   });
  

• UpdateRecord(record: any): Promise

  Modify catalog record

   csw.UpdateRecord(records).then((data) => {
     ... // your code
   });
  

• DeleteRecords(filters: IFilterField[]): Promise

  Delete catalog records according to defined filter

   csw.DeleteRecords(filters).then((data) => {
     ... // your code
   });
  

Utils

• xmlStringToJson(xmlString: string): any

  Converts XML-like string to JSON object according to defined schemas

   const obj = csw.xmlStringToJson(xmlString);
  

• jsonToXml(json: any): XMLDocument
  Converts JSON object to XMLDocument according to defined schemas

   const xmlDoc: XMLDocument = csw.jsonToXml(json);
  

• xmlToJson(xml: XMLDocument): any

  Converts XMLDocument to JSON object according to defined schemas

   const obj = csw.xmlToJson(xml);
  

• xmlToString(xml: XMLDocument): string

  Converts XMLDocument to XML-like string according to defined schemas

   const str = csw.xmlToString(xml);
  

OGC Filters

• Operators:

  • Logical Operators:
    • AND

        let filter: any = new FilterBuilder().PropertyName('dc:title').isLike('%water%');
        filter = filter.and(new FilterBuilder().PropertyName('dc:subject').isLike('%polution%'));
    

    • OR

        let filter: any = new FilterBuilder().PropertyName('dc:title').isLike('%water%');
        filter = filter.or(new FilterBuilder().PropertyName('dc:title').isLike('%oil%'));
    

• Spatial Operatos:

  • BBOX

  let filter: any = new FilterBuilder().PropertyName('dc:title').isLike('%water%');
  filter = filter.and(new FilterBuilder().BBOX(-80, 150, 80, -150));
  

• Comparison

  • isLike
  • isBetween
  • isEqualTo
  • isLessThanOrEqualTo
  • isGreaterThan
  • isLessThan
  • isGreaterThanOrEqualTo
  • isNotEqualTo

OGC Sort

  const sort: SortBuilder = new SortBuilder().Sort('dc:title');
  sort.Sort('dc:dummy', true);

Applyed patches ( ./patches/*.patch )

• Jsonix/ogc-schemas BBOX schema(s) definition
  • Discussion is here: https://github.com/OSGeo/ows.js/issues/9
• Jsonix webback-dev-server issue
  • Discussion is here: https://github.com/highsource/jsonix/issues/171
  • Applied patch based on: https://github.com/planetfederal/jsonix/commit/d88f68d1a62a14c09562b15cf0e6ce5e1f14fbf2