graphql-ld/lib/Client.d.ts

Linked Data Querying with GraphQL

import { Converter as GraphQlToSparqlConverter } from "graphql-to-sparql";
import { ISingularizeVariables } from "graphql-to-sparql/lib/IConvertContext";
import { ExecutionResult } from "graphql/execution/execute";
import { DocumentNode } from "graphql/language";
import { ContextParser, JsonLdContext } from "jsonld-context-parser";
import * as RDF from "@rdfjs/types";
import { Algebra } from "sparqlalgebrajs";
import { Converter as SparqlJsonToTreeConverter } from "sparqljson-to-tree";
import { IQueryEngine } from "./IQueryEngine";
/**
 * A GraphQL-LD client.
 *
 * Typical usage:
 * ```
 * const client = new Client({ context, queryEngine });
 * const { data } = await client.query({ query: `{ books { name author { name } } }` });
 * ```
 */
export declare class Client {
    private readonly context;
    private readonly queryEngine;
    private readonly graphqlToSparqlConverter;
    private readonly sparqlJsonToTreeConverter;
    constructor(args: IClientArgs);
    /**
     * Execute a GraphQL-LD query.
     *
     * There are three ways of invoking this methods:
     * 1. with a GraphQL query string and optional variables:
     *    `client.query({ query: `{...}`, variables: { varName: 123 } })`
     * 2. with a parsed GraphQL query and optional variables:
     *    `client.query({ query: gql`{...}`, variables: { varName: 123 } })`
     * 3. with a SPARQL algebra object and a singularizeVariables object
     *    `client.query({ sparqlAlgebra, singularizeVariables })`
     *    This corresponds to the result of {@link Client#graphQlToSparql}.
     *
     * @param {QueryArgs} args Query+variables, or SPARQL algebra+singularize variables.
     * @return {Promise<ExecutionResult>} A promise resolving to a GraphQL result.
     */
    query(args: QueryArgs): Promise<ExecutionResult>;
    /**
     * Convert a GraphQL query to SPARQL algebra and a singularize variables object.
     * @param {string | DocumentNode} query
     * @param {{[p: string]: any}} variables
     * @return {Promise<IGraphQlToSparqlResult>}
     */
    graphQlToSparql({ query, variables }: IQueryArgsRaw): Promise<IGraphQlToSparqlResult>;
}
export interface IClientArgs {
    /**
     * A JSON-LD context.
     * This may be an object, array, or a string (URL to remote context)
     */
    context: JsonLdContext;
    /**
     * A query engine that will be used to execute SPARQL queries.
     */
    queryEngine: IQueryEngine;
    /**
     * An optional base IRI.
     */
    baseIRI?: string;
    /**
     * An optional data factory for RDF quads and terms.
     */
    dataFactory?: RDF.DataFactory;
    /**
     * An optional JSON-LD context parser.
     * Provide this to override the default context parser options.
     */
    contextParser?: ContextParser;
    /**
     * An optional GraphQL to SPARQL converter.
     * Provide this to override the default converter options.
     */
    graphqlToSparqlConverter?: GraphQlToSparqlConverter;
    /**
     * An optional SPARQL-JSON to GraphQL tree converter.
     * Provide this to override the default converter options.
     */
    sparqlJsonToTreeConverter?: SparqlJsonToTreeConverter;
}
export type QueryArgs = IQueryArgsRaw | IQueryArgsSparql;
export interface IQueryArgsRaw {
    query: string | DocumentNode;
    variables?: {
        [key: string]: any;
    };
    queryEngineOptions?: any;
}
export interface IQueryArgsSparql extends IGraphQlToSparqlResult {
    queryEngineOptions?: any;
}
export interface IGraphQlToSparqlResult {
    sparqlAlgebra: Algebra.Operation;
    singularizeVariables: ISingularizeVariables;
}