@benzene/core/dist/index.js

Fast, minimal, agnostic GraphQL Libraries

import { execute, subscribe, GraphQLError, validate, GraphQLSchema, validateSchema, print, parse, getOperationAST } from 'graphql';
import lru from 'tiny-lru';

function isAsyncIterator(val) {
    return typeof Object(val)[Symbol.asyncIterator] === "function";
}
/**
 * Create a compileQuery function using graphql-js
 * @returns CompileQuery
 */
function makeCompileQuery() {
    return function compileQuery(schema) {
        return {
            execute(args) {
                return execute({ ...args, schema });
            },
            subscribe(args) {
                return subscribe({ ...args, schema });
            },
        };
    };
}
function isExecutionResult(val) {
    return (typeof val === "object" &&
        val !== null &&
        (Array.isArray(val.errors) ||
            (typeof val.data === "object" &&
                !Array.isArray(val.data))));
}
/**
 * Validate whether an operation does not exist
 * or operationName is missing. Even though
 * execution will realize this, we need to provide
 * this hint mainly for handlers to avoid execution
 * @param operation
 * @param operationName
 */
function validateOperationName(operation, operationName) {
    if (operation)
        return [];
    if (!operationName) {
        return [
            new GraphQLError("Must provide operation name if query contains multiple operations."),
        ];
    }
    return [new GraphQLError(`Unknown operation named "${operationName}".`)];
}
/**
 * Given a GraphQLError, format it according to the rules described by the
 * Response Format, Errors section of the GraphQL Specification.
 */
function formatError(error) {
    const formattedError = {
        message: error.message,
    };
    if (error.locations != null) {
        formattedError.locations = error.locations;
    }
    if (error.path != null) {
        formattedError.path = error.path;
    }
    if (error.extensions != null && Object.keys(error.extensions).length > 0) {
        formattedError.extensions = error.extensions;
    }
    return formattedError;
}

class Benzene {
    constructor(options) {
        if (!options)
            throw new TypeError("GQL must be initialized with options");
        this.validateFn = options.validateFn || validate;
        this.validationRules = options.validationRules;
        this.formatErrorFn = options.formatErrorFn || formatError;
        this.contextFn = options.contextFn;
        // build cache
        this.lru = lru(1024);
        // construct schema and validate
        if (!(options.schema instanceof GraphQLSchema)) {
            throw new Error(`Expected ${options.schema} to be a GraphQL schema.`);
        }
        const schemaValidationErrors = validateSchema(options.schema);
        if (schemaValidationErrors.length > 0) {
            throw schemaValidationErrors;
        }
        this.schema = options.schema;
        this.compileQuery = options.compileQuery || makeCompileQuery();
    }
    compile(query, operationName) {
        let document;
        if (typeof query === "object") {
            // query is DocumentNode
            document = query;
            query = print(document);
        }
        const key = query + (operationName ? `:${operationName}` : "");
        let cached = this.lru.get(key);
        if (cached) {
            return cached;
        }
        else {
            if (!document) {
                if (!query)
                    throw new Error("Must provide document.");
                try {
                    document = parse(query);
                }
                catch (syntaxErr) {
                    return {
                        errors: [syntaxErr],
                    };
                }
            }
            const validationErrors = this.validateFn(this.schema, document, this.validationRules);
            if (validationErrors.length > 0) {
                return {
                    errors: validationErrors,
                };
            }
            const compiled = this.compileQuery(this.schema, document, operationName);
            // Compilation is a failure since its result is ExecutionResult
            if (isExecutionResult(compiled))
                return compiled;
            cached = compiled;
            cached.document = document;
            const operation = getOperationAST(document, operationName)?.operation;
            if (operation) {
                // If we could not determine the operation, it is unsafe to cache
                cached.operation = operation;
                this.lru.set(key, cached);
            }
            return cached;
        }
    }
    formatExecutionResult(result) {
        const o = {};
        if (result.data)
            o.data = result.data;
        if (result.errors)
            o.errors = result.errors.map(this.formatErrorFn);
        return o;
    }
    async graphql({ source, contextValue, variableValues, operationName, rootValue, }) {
        const cachedOrResult = this.compile(source, operationName);
        if (isExecutionResult(cachedOrResult))
            return cachedOrResult;
        return this.execute({
            document: cachedOrResult.document,
            contextValue,
            variableValues,
            rootValue,
            operationName,
            compiled: cachedOrResult,
        });
    }
    execute(args) {
        if (!args.compiled) {
            if (!args.document)
                throw new Error("Must provide document.");
            const compiledOrResult = this.compile(args.document);
            if (isExecutionResult(compiledOrResult))
                return compiledOrResult;
            args.compiled = compiledOrResult;
        }
        else {
            args.document = args.compiled.document;
        }
        return args.compiled.execute(args);
    }
    async subscribe(args) {
        if (!args.compiled) {
            if (!args.document)
                throw new Error("Must provide document.");
            const compiledOrResult = this.compile(args.document);
            if (isExecutionResult(compiledOrResult))
                return compiledOrResult;
            args.compiled = compiledOrResult;
        }
        else {
            args.document = args.compiled.document;
        }
        return args.compiled.subscribe(args);
    }
}

export { Benzene, isAsyncIterator, isExecutionResult, makeCompileQuery, validateOperationName };