| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.tinkerpop.gremlin.jsr223; |
| |
| import java.util.Arrays; |
| import java.util.HashSet; |
| import java.util.Optional; |
| import java.util.Set; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| /** |
| * Processes Gremlin strings using regex to try to detect certain properties from the script without actual |
| * having to execute a {@code eval()} on it. |
| */ |
| public class GremlinScriptChecker { |
| |
| /** |
| * An empty result whose properties return as empty. |
| */ |
| public static final Result EMPTY_RESULT = new Result(null, null); |
| |
| /** |
| * At least one of these tokens should be present somewhere in the Gremlin string for {@link #parse(String)} to |
| * take any action at all. |
| */ |
| private static final Set<String> tokens = new HashSet<>(Arrays.asList("evaluationTimeout", "scriptEvaluationTimeout", |
| "ARGS_EVAL_TIMEOUT", "ARGS_SCRIPT_EVAL_TIMEOUT", |
| "requestId", "REQUEST_ID")); |
| /** |
| * Matches single line comments, multi-line comments and space characters. |
| * <pre> |
| * From https://regex101.com/ |
| * |
| * OR: match either of the followings |
| * Sequence: match all of the followings in order |
| * / / |
| * Repeat |
| * AnyCharacterExcept\n |
| * zero or more times |
| * EndOfLine |
| * Sequence: match all of the followings in order |
| * / |
| * * |
| * Repeat |
| * CapturingGroup |
| * GroupNumber:1 |
| * OR: match either of the followings |
| * AnyCharacterExcept\n |
| * AnyCharIn[ CarriageReturn NewLine] |
| * zero or more times (ungreedy) |
| * * |
| * / |
| * WhiteSpaceCharacter |
| * </pre> |
| */ |
| private static final Pattern patternClean = Pattern.compile("//.*$|/\\*(.|[\\r\\n])*?\\*/|\\s", Pattern.MULTILINE); |
| |
| /** |
| * Regex fragment for the timeout tokens to look for. There are basically four: |
| * <ul> |
| * <li>{@code evaluationTimeout} which is a string value and thus single or double quoted</li> |
| * <li>{@code scriptEvaluationTimeout} which is a string value and thus single or double quoted</li> |
| * <li>{@code ARGS_EVAL_TIMEOUT} which is a enum type of value which can be referenced with or without a {@code Tokens} qualifier</li> |
| * <li>{@code ARGS_SCRIPT_EVAL_TIMEOUT} which is a enum type of value which can be referenced with or without a {@code Tokens} qualifier</li> |
| * </ul> |
| * See {@link #patternWithOptions} for explain as this regex is embedded in there. |
| */ |
| private static final String timeoutTokens = "[\"']evaluationTimeout[\"']|[\"']scriptEvaluationTimeout[\"']|(?:Tokens\\.)?ARGS_EVAL_TIMEOUT|(?:Tokens\\.)?ARGS_SCRIPT_EVAL_TIMEOUT"; |
| |
| /** |
| * Regex fragment for the timeout tokens to look for. There are basically four: |
| * <ul> |
| * <li>{@code requestId} which is a string value and thus single or double quoted</li> |
| * <li>{@code REQUEST_ID} which is a enum type of value which can be referenced with or without a {@code Tokens} qualifier</li> |
| * </ul> |
| * See {@link #patternWithOptions} for a full explain as this regex is embedded in there. |
| */ |
| private static final String requestIdTokens = "[\"']requestId[\"']|(?:Tokens\\.)?REQUEST_ID"; |
| |
| /** |
| * Matches {@code .with({timeout-token},{timeout})} with a matching group on the {@code timeout}. |
| * |
| * <pre> |
| * From https://regex101.com/ |
| * |
| * \.with\((?:(?:["']evaluationTimeout["']|["']scriptEvaluationTimeout["']|(?:Tokens\.)?ARGS_EVAL_TIMEOUT|(?:Tokens\.)?ARGS_SCRIPT_EVAL_TIMEOUT),(?<to>\d*)(:?L|l)?)|(?:(?:["']requestId["']|(?:Tokens\.)?REQUEST_ID),["'](?<rid>.*?))["']\) |
| * |
| * gm |
| * 1st Alternative \.with\((?:(?:["']evaluationTimeout["']|["']scriptEvaluationTimeout["']|(?:Tokens\.)?ARGS_EVAL_TIMEOUT|(?:Tokens\.)?ARGS_SCRIPT_EVAL_TIMEOUT),(?<to>\d*)(:?L|l)?) |
| * \. matches the character . with index 4610 (2E16 or 568) literally (case sensitive) |
| * with matches the characters with literally (case sensitive) |
| * \( matches the character ( with index 4010 (2816 or 508) literally (case sensitive) |
| * Non-capturing group (?:(?:["']evaluationTimeout["']|["']scriptEvaluationTimeout["']|(?:Tokens\.)?ARGS_EVAL_TIMEOUT|(?:Tokens\.)?ARGS_SCRIPT_EVAL_TIMEOUT),(?<to>\d*)(:?L|l)?) |
| * Non-capturing group (?:["']evaluationTimeout["']|["']scriptEvaluationTimeout["']|(?:Tokens\.)?ARGS_EVAL_TIMEOUT|(?:Tokens\.)?ARGS_SCRIPT_EVAL_TIMEOUT) |
| * 1st Alternative ["']evaluationTimeout["'] |
| * Match a single character present in the list below ["'] |
| * "' matches a single character in the list "' (case sensitive) |
| * evaluationTimeout matches the characters evaluationTimeout literally (case sensitive) |
| * Match a single character present in the list below ["'] |
| * "' matches a single character in the list "' (case sensitive) |
| * 2nd Alternative ["']scriptEvaluationTimeout["'] |
| * Match a single character present in the list below ["'] |
| * "' matches a single character in the list "' (case sensitive) |
| * scriptEvaluationTimeout matches the characters scriptEvaluationTimeout literally (case sensitive) |
| * Match a single character present in the list below ["'] |
| * "' matches a single character in the list "' (case sensitive) |
| * 3rd Alternative (?:Tokens\.)?ARGS_EVAL_TIMEOUT |
| * Non-capturing group (?:Tokens\.)? |
| * ? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy) |
| * Tokens matches the characters Tokens literally (case sensitive) |
| * \. matches the character . with index 4610 (2E16 or 568) literally (case sensitive) |
| * ARGS_EVAL_TIMEOUT matches the characters ARGS_EVAL_TIMEOUT literally (case sensitive) |
| * 4th Alternative (?:Tokens\.)?ARGS_SCRIPT_EVAL_TIMEOUT |
| * Non-capturing group (?:Tokens\.)? |
| * ? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy) |
| * Tokens matches the characters Tokens literally (case sensitive) |
| * \. matches the character . with index 4610 (2E16 or 568) literally (case sensitive) |
| * ARGS_SCRIPT_EVAL_TIMEOUT matches the characters ARGS_SCRIPT_EVAL_TIMEOUT literally (case sensitive) |
| * , matches the character , with index 4410 (2C16 or 548) literally (case sensitive) |
| * Named Capture Group to (?<to>\d*) |
| * \d matches a digit (equivalent to [0-9]) |
| * * matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy) |
| * 2nd Capturing Group (:?L|l)? |
| * ? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy) |
| * 1st Alternative :?L |
| * : matches the character : with index 5810 (3A16 or 728) literally (case sensitive) |
| * ? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy) |
| * L matches the character L with index 7610 (4C16 or 1148) literally (case sensitive) |
| * 2nd Alternative l |
| * l matches the character l with index 10810 (6C16 or 1548) literally (case sensitive) |
| * 2nd Alternative (?:(?:["']requestId["']|(?:Tokens\.)?REQUEST_ID),["'](?<rid>.*?))["']\) |
| * Non-capturing group (?:(?:["']requestId["']|(?:Tokens\.)?REQUEST_ID),["'](?<rid>.*?)) |
| * Non-capturing group (?:["']requestId["']|(?:Tokens\.)?REQUEST_ID) |
| * 1st Alternative ["']requestId["'] |
| * 2nd Alternative (?:Tokens\.)?REQUEST_ID |
| * , matches the character , with index 4410 (2C16 or 548) literally (case sensitive) |
| * Match a single character present in the list below ["'] |
| * "' matches a single character in the list "' (case sensitive) |
| * Named Capture Group rid (?<rid>.*?) |
| * . matches any character (except for line terminators) |
| * *? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy) |
| * Match a single character present in the list below ["'] |
| * "' matches a single character in the list "' (case sensitive) |
| * \) matches the character ) with index 4110 (2916 or 518) literally (case sensitive) |
| * </pre> |
| */ |
| private static final Pattern patternWithOptions = |
| Pattern.compile("\\.with\\(((?:" + timeoutTokens + "),(?<to>\\d*)(:?L|l)?)|((?:" + requestIdTokens + "),[\"'](?<rid>.*?))[\"']\\)"); |
| |
| /** |
| * Parses a Gremlin script and extracts a {@code Result} containing properties that are relevant to the checker. |
| */ |
| public static Result parse(final String gremlin) { |
| if (gremlin.isEmpty()) return EMPTY_RESULT; |
| |
| // do a cheap check for tokens we care about - no need to parse unless one of these tokens is present in |
| // the string. |
| if (tokens.stream().noneMatch(gremlin::contains)) return EMPTY_RESULT; |
| |
| // kill out comments/whitespace. for whitespace, ignoring the need to keep string literals together as that |
| // isn't currently a requirement |
| final String cleanGremlin = patternClean.matcher(gremlin).replaceAll(""); |
| |
| final Matcher m = patternWithOptions.matcher(cleanGremlin); |
| if (!m.find()) return EMPTY_RESULT; |
| |
| // arguments given to Result class as null mean they weren't assigned (or the parser didn't find them somehow - eek!) |
| Long timeout = null; |
| String requestId = null; |
| do { |
| // timeout is added up across all scripts |
| final String to = m.group("to"); |
| if (to != null) { |
| if (null == timeout) timeout = 0L; |
| timeout += Long.parseLong(to); |
| } |
| |
| // request id just uses the last one found |
| final String rid = m.group("rid"); |
| if (rid != null) requestId = rid; |
| } while (m.find()); |
| |
| return new Result(timeout, requestId); |
| } |
| |
| /** |
| * A result returned from a {@link #parse(String)} of a Gremlin string. |
| */ |
| public static class Result { |
| private final Long timeout; |
| private final String requestId; |
| |
| private Result(final Long timeout, final String requestId) { |
| this.timeout = timeout; |
| this.requestId = requestId; |
| } |
| |
| /** |
| * Gets the value of the timeouts that were set using the {@code with()} source step. If there are multiple |
| * commands using this step, the timeouts are summed together. |
| */ |
| public final Optional<Long> getTimeout() { |
| return null == timeout ? Optional.empty() : Optional.of(timeout); |
| } |
| |
| /** |
| * Gets the value of the request identifier supplied using the {@code with()} source step. If there are |
| * multiple commands using this step, the last usage should represent the id returned here. |
| */ |
| public Optional<String> getRequestId() { |
| return null == requestId ? Optional.empty() : Optional.of(requestId); |
| } |
| |
| @Override |
| public String toString() { |
| return "GremlinScriptChecker.Result{" + |
| "timeout=" + timeout + |
| ", requestId='" + requestId + '\'' + |
| '}'; |
| } |
| } |
| } |
