package io.vertx.ext.web.api.contract.openapi3.impl;

import io.swagger.v3.oas.models.parameters.Parameter;
import io.vertx.ext.web.api.contract.RouterFactoryException;

import static io.vertx.ext.web.api.contract.openapi3.impl.OpenApi3Utils.safeBoolean;

import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Collectors;

Author:Francesco Guardiani @slinkydeveloper
/** * @author Francesco Guardiani @slinkydeveloper */
public class OpenAPI3PathResolver { String oasPath; List<Parameter> parameters; Pattern resolvedPattern; //Key is new name, value is old name Map<String, String> mappedGroups; public static final Pattern OAS_PATH_PARAMETERS_PATTERN = Pattern.compile("\\{{1}[.;?*+]*([^\\{\\}.;?*+]+)[^\\}]*\\}{1}"); public static final Pattern ILLEGAL_PATH_MATCHER = Pattern.compile("\\{[^\\/]*\\/[^\\/]*\\}"); private boolean shouldThreatDotAsReserved; public OpenAPI3PathResolver(String oasPath, List<Parameter> parameters) { this.oasPath = oasPath; // Filter parameters to get only path parameters if (parameters != null) this.parameters = parameters.stream().filter(parameter -> parameter.getIn().equals("path")).collect(Collectors.toList()); else this.parameters = new ArrayList<>(); // If there's a parameter with label style, the dot should be escaped to avoid conflicts this.shouldThreatDotAsReserved = hasParameterWithStyle("label"); this.mappedGroups = new HashMap<>(); }
This method returns a pattern only if a pattern is needed, otherwise it returns an empty optional
Returns:
/** * This method returns a pattern only if a pattern is needed, otherwise it returns an empty optional * * @return */
public Optional<Pattern> solve() { if (ILLEGAL_PATH_MATCHER.matcher(oasPath).matches()) throw new RouterFactoryException("Path template not supported", RouterFactoryException.ErrorType.INVALID_SPEC_PATH); Matcher parametersMatcher = OAS_PATH_PARAMETERS_PATTERN.matcher(oasPath); if (!parameters.isEmpty() && parametersMatcher.find()) { // Need to create a specific match pattern with path parameters and some string manipulation magic StringBuilder regex = new StringBuilder(); int lastMatchEnd = 0; boolean endSlash = oasPath.charAt(oasPath.length() - 1) == '/'; parametersMatcher.reset(); int i = 0; while (parametersMatcher.find()) { // Append constant string String toQuote = oasPath.substring(lastMatchEnd, parametersMatcher.start()); if (toQuote.length() != 0) regex.append(Pattern.quote(toQuote)); lastMatchEnd = parametersMatcher.end(); String paramName = parametersMatcher.group(1); Optional<Parameter> parameterOptional = parameters.stream().filter(p -> p.getName().equals(paramName)).findFirst(); if (parameterOptional.isPresent()) { // For every parameter style I have to generate a different regular expression Parameter parameter = parameterOptional.get(); String style = solveParamStyle(parameter); boolean explode = solveParamExplode(parameter); boolean isObject = OpenApi3Utils.isParameterObjectOrAllOfType(parameter); boolean isArray = OpenApi3Utils.isParameterArrayType(parameter); String groupName = "p" + i; /* +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | style | explode | empty | string | array | object | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | matrix | false | ;color | ;color=blue | ;color=blue,black,brown | ;color=R,100,G,200,B,150 | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | matrix | true | ;color | ;color=blue | ;color=blue;color=black;color=brown | ;R=100;G=200;B=150 | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | label | false | . | .blue | .blue.black.brown | .R.100.G.200.B.150 | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | label | true | . | .blue | .blue.black.brown | .R=100.G=200.B=150 | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | simple | false | n/a | blue | blue,black,brown | R,100,G,200,B,150 | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ | simple | true | n/a | blue | blue,black,brown | R=100,G=200,B=150 | +--------+---------+--------+-------------+-------------------------------------+--------------------------+ RFC 3986 section 2.2 Reserved Characters (January 2005) ! * ' ( ) ; : @ & = + $ , / ? # [ ] */ if (style.equals("simple")) { regex.append( RegexBuilder.create().namedGroup( groupName, RegexBuilder.create().notCharactersClass( "!", "*", "'", "(", ")", ";", "@", "&", "+", "$", "/", "?", "#", "[", "]", (shouldThreatDotAsReserved) ? "." : null ).zeroOrMore() ).zeroOrOne() ); mappedGroups.put(groupName, paramName); } else if (style.equals("label")) { if (isObject && explode) { Map<String, OpenApi3Utils.ObjectField> properties = OpenApi3Utils.solveObjectParameters(parameter.getSchema()); for (Map.Entry<String, OpenApi3Utils.ObjectField> entry : properties.entrySet()) { groupName = "p" + i; regex.append( RegexBuilder.create().optionalGroup( RegexBuilder.create() .escapeCharacter(".").zeroOrOne().quote(entry.getKey()).append("=") .namedGroup(groupName, RegexBuilder.create().notCharactersClass( "!", "*", "'", "(", ")", ";", "@", "&", "+", "$", "/", "?", "#", "[", "]", ".", "=" ).zeroOrMore() ) ) ); mappedGroups.put(groupName, entry.getKey()); i++; } } else { regex.append( RegexBuilder.create() .escapeCharacter(".").zeroOrOne() .namedGroup(groupName, RegexBuilder.create().notCharactersClass( "!", "*", "'", "(", ")", ";", "@", "&", "=", "+", "$", ",", "/", "?", "#", "[", "]" ).zeroOrMore() ).zeroOrOne() ); mappedGroups.put(groupName, paramName); } } else if (style.equals("matrix")) { if (isObject && explode) { Map<String, OpenApi3Utils.ObjectField> properties = OpenApi3Utils.solveObjectParameters(parameter.getSchema()); for (Map.Entry<String, OpenApi3Utils.ObjectField> entry : properties.entrySet()) { groupName = "p" + i; regex.append( RegexBuilder.create().optionalGroup( RegexBuilder.create() .escapeCharacter(";").quote(entry.getKey()).append("=") .namedGroup(groupName, RegexBuilder.create().notCharactersClass( "!", "*", "'", "(", ")", ";", "@", "&", "=", "+", "$", ",", "/", "?", "#", "[", "]", (shouldThreatDotAsReserved) ? "." : null ).zeroOrMore() ) ) ); mappedGroups.put(groupName, entry.getKey()); i++; } } else if (isArray && explode) { regex.append( RegexBuilder.create().namedGroup( groupName, RegexBuilder.create().atomicGroup( RegexBuilder.create() .append(";").quote(paramName).append("=") .notCharactersClass( "!", "*", "'", "(", ")", ";", "@", "&", "=", "+", "$", ",", "/", "?", "#", "[", "]", (shouldThreatDotAsReserved) ? "." : null ).zeroOrMore() ).oneOrMore() ) ); mappedGroups.put(groupName, paramName); } else { regex.append( RegexBuilder.create() .append(";").quote(paramName).append("=") .namedGroup( groupName, RegexBuilder.create().notCharactersClass( "!", "*", "'", "(", ")", ";", "@", "&", "=", "+", "$", "/", "?", "#", "[", "]", (shouldThreatDotAsReserved) ? "." : null ).zeroOrMore() ).zeroOrOne() ); mappedGroups.put(groupName, paramName); } } } else { throw RouterFactoryException.createSpecInvalidException("Missing parameter description for parameter name: " + paramName); } i++; } String toAppendQuoted = oasPath.substring(lastMatchEnd, (endSlash) ? oasPath.length() - 1 : oasPath.length()); if (toAppendQuoted.length() != 0) regex.append(Pattern.quote(toAppendQuoted)); if (endSlash) regex.append("\\/"); return Optional.of(Pattern.compile(regex.toString())); } else { return Optional.empty(); } } public Pattern getResolvedPattern() { return resolvedPattern; } public Map<String, String> getMappedGroups() { return mappedGroups; } private String solveParamStyle(Parameter parameter) { return (parameter.getStyle() != null) ? parameter.getStyle().toString() : "simple"; } private boolean solveParamExplode(Parameter parameter) { return safeBoolean.apply(parameter.getExplode()); } private boolean hasParameterWithStyle(String style) { return parameters.stream().map(this::solveParamStyle).anyMatch(s -> s.equals(style)); } }