adaptive-expressions
Version:
Common Expression Language
65 lines (58 loc) • 2.13 kB
text/typescript
/**
* @module adaptive-expressions
*/
/**
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License.
*/
import { Expression } from '../expression';
import { ExpressionEvaluator, ValueWithError } from '../expressionEvaluator';
import { ExpressionType } from '../expressionType';
import { FunctionUtils } from '../functionUtils';
import { InternalFunctionUtils } from '../functionUtils.internal';
import { MemoryInterface } from '../memory/memoryInterface';
import { Options } from '../options';
import { ReturnType } from '../returnType';
/**
* Return the scheme value of a unified resource identifier (URI).
*/
export class UriScheme extends ExpressionEvaluator {
/**
* Initializes a new instance of the [UriScheme](xref:adaptive-expressions.UriScheme) class.
*/
constructor() {
super(ExpressionType.UriScheme, UriScheme.evaluator, ReturnType.String, FunctionUtils.validateUnary);
}
/**
* @private
*/
private static evaluator(expr: Expression, state: MemoryInterface, options: Options): ValueWithError {
let value: any;
const { args, error: childrenError } = FunctionUtils.evaluateChildren(expr, state, options);
let error = childrenError;
if (!error) {
if (typeof args[0] === 'string') {
({ value, error } = UriScheme.evalUriScheme(args[0]));
} else {
error = `${expr} should contain a URI string.`;
}
}
return { value, error };
}
/**
* @private
*/
private static evalUriScheme(uri: string): ValueWithError {
let result: string;
const { value: parsed, error: parseError } = InternalFunctionUtils.parseUri(uri);
let error = parseError;
if (!error) {
try {
result = parsed.protocol.replace(':', '');
} catch {
error = 'invalid operation, input uri should be an absolute URI';
}
}
return { value: result, error };
}
}