com.google.gerrit.server.mail.receive.HtmlParser.java Source code

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Here is the source code for com.google.gerrit.server.mail.receive.HtmlParser.java

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// Copyright (C) 2016 The Android Open Source Project
//
// Licensed 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 com.google.gerrit.server.mail.receive;

import com.google.common.base.Strings;
import com.google.common.collect.Iterators;
import com.google.common.collect.PeekingIterator;
import com.google.gerrit.reviewdb.client.Comment;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;

/** HTMLParser provides parsing functionality for html email. */
public class HtmlParser {
    /**
     * Parses comments from html email.
     *
     * @param email MailMessage as received from the email service.
     * @param comments A specific set of comments as sent out in the original notification email.
     *     Comments are expected to be in the same order as they were sent out to in the email
     * @param changeUrl Canonical change URL that points to the change on this Gerrit instance.
     *     Example: https://go-review.googlesource.com/#/c/91570
     * @return List of MailComments parsed from the html part of the email.
     */
    public static List<MailComment> parse(MailMessage email, Collection<Comment> comments, String changeUrl) {
        // TODO(hiesel) Add support for Gmail Mobile
        // TODO(hiesel) Add tests for other popular email clients

        // This parser goes though all html elements in the email and checks for
        // matching patterns. It keeps track of the last file and comments it
        // encountered to know in which context a parsed comment belongs.
        // It uses the href attributes of <a> tags to identify comments sent out by
        // Gerrit as these are generally more reliable then the text captions.
        List<MailComment> parsedComments = new ArrayList<>();
        Document d = Jsoup.parse(email.htmlContent());
        PeekingIterator<Comment> iter = Iterators.peekingIterator(comments.iterator());

        String lastEncounteredFileName = null;
        Comment lastEncounteredComment = null;
        for (Element e : d.body().getAllElements()) {
            String elementName = e.tagName();
            boolean isInBlockQuote = e.parents().stream().filter(p -> p.tagName().equals("blockquote")).findAny()
                    .isPresent();

            if (elementName.equals("a")) {
                String href = e.attr("href");
                // Check if there is still a next comment that could be contained in
                // this <a> tag
                if (!iter.hasNext()) {
                    continue;
                }
                Comment perspectiveComment = iter.peek();
                if (href.equals(ParserUtil.filePath(changeUrl, perspectiveComment))) {
                    if (lastEncounteredFileName == null
                            || !lastEncounteredFileName.equals(perspectiveComment.key.filename)) {
                        // Not a file-level comment, but users could have typed a comment
                        // right after this file annotation to create a new file-level
                        // comment. If this file has a file-level comment, we have already
                        // set lastEncounteredComment to that file-level comment when we
                        // encountered the file link and should not reset it now.
                        lastEncounteredFileName = perspectiveComment.key.filename;
                        lastEncounteredComment = null;
                    } else if (perspectiveComment.lineNbr == 0) {
                        // This was originally a file-level comment
                        lastEncounteredComment = perspectiveComment;
                        iter.next();
                    }
                } else if (ParserUtil.isCommentUrl(href, changeUrl, perspectiveComment)) {
                    // This is a regular inline comment
                    lastEncounteredComment = perspectiveComment;
                    iter.next();
                }
            } else if (!isInBlockQuote && elementName.equals("div") && !e.className().startsWith("gmail")) {
                // This is a comment typed by the user
                // Replace non-breaking spaces and trim string
                String content = e.ownText().replace('\u00a0', ' ').trim();
                if (!Strings.isNullOrEmpty(content)) {
                    if (lastEncounteredComment == null && lastEncounteredFileName == null) {
                        // Remove quotation line, email signature and
                        // "Sent from my xyz device"
                        content = ParserUtil.trimQuotation(content);
                        // TODO(hiesel) Add more sanitizer
                        if (!Strings.isNullOrEmpty(content)) {
                            parsedComments.add(
                                    new MailComment(content, null, null, MailComment.CommentType.CHANGE_MESSAGE));
                        }
                    } else if (lastEncounteredComment == null) {
                        parsedComments.add(new MailComment(content, lastEncounteredFileName, null,
                                MailComment.CommentType.FILE_COMMENT));
                    } else {
                        parsedComments.add(new MailComment(content, null, lastEncounteredComment,
                                MailComment.CommentType.INLINE_COMMENT));
                    }
                }
            }
        }
        return parsedComments;
    }
}