Merge "Add MetadataParser for inbound email"

gerrit-server/src/main/java/com/google/gerrit/server/mail/MailUtil.java

@@ -28,6 +28,7 @@ import com.google.gwtorm.server.OrmException;
 import org.eclipse.jgit.revwalk.FooterKey;
 import org.eclipse.jgit.revwalk.FooterLine;
 
+import java.time.format.DateTimeFormatter;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
@@ -35,6 +36,9 @@ import java.util.Set;
 import java.util.regex.Pattern;
 
 public class MailUtil {
+  public static DateTimeFormatter rfcDateformatter =
+      DateTimeFormatter.ofPattern("EEE, dd MMM yyyy HH:mm:ss ZZZ");
+
   public static MailRecipients getRecipientsFromFooters(
       ReviewDb db, AccountResolver accountResolver, boolean draftPatchSet,
       List<FooterLine> footerLines) throws OrmException {

gerrit-server/src/main/java/com/google/gerrit/server/mail/MetadataName.java

@@ -0,0 +1,34 @@
+// 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;
+
+public final class MetadataName {
+  public static final String CHANGE_ID = "Gerrit-Change-Id";
+  public static final String PATCH_SET = "Gerrit-PatchSet";
+  public static final String MESSAGE_TYPE = "Gerrit-MessageType";
+  public static final String TIMESTAMP = "Gerrit-Comment-Date";
+
+  public static String toHeader(String metadataName) {
+    return "X-" + metadataName;
+  }
+
+  public static String toHeaderWithDelimiter(String metadataName) {
+    return toHeader(metadataName) + ": ";
+  }
+
+  public static String toFooterWithDelimiter(String metadataName) {
+    return metadataName + ": ";
+  }
+}

gerrit-server/src/main/java/com/google/gerrit/server/mail/receive/MailMetadata.java

@@ -0,0 +1,45 @@
+// 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.MoreObjects;
+
+import java.sql.Timestamp;
+
+/** MailMetadata represents metadata parsed from inbound email. */
+public class MailMetadata {
+  public String changeId;
+  public Integer patchSet;
+  public String author; // Author of the email
+  public Timestamp timestamp;
+  public String messageType; // we expect comment here
+
+
+  public boolean hasRequiredFields() {
+    return changeId != null && patchSet != null && author != null &&
+        timestamp != null && messageType != null;
+  }
+
+  @Override
+  public String toString() {
+    return MoreObjects.toStringHelper(this)
+        .add("Change-Id", changeId)
+        .add("Patch-Set", patchSet)
+        .add("Author", author)
+        .add("Timestamp", timestamp)
+        .add("Message-Type", messageType)
+        .toString();
+  }
+}

gerrit-server/src/main/java/com/google/gerrit/server/mail/receive/MetadataParser.java

@@ -0,0 +1,110 @@
+// 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 static com.google.gerrit.server.mail.MetadataName.toHeaderWithDelimiter;
+import static com.google.gerrit.server.mail.MetadataName.toFooterWithDelimiter;
+
+import com.google.common.base.Strings;
+import com.google.common.primitives.Ints;
+
+import com.google.gerrit.server.mail.MailUtil;
+import com.google.gerrit.server.mail.MetadataName;
+
+import java.sql.Timestamp;
+import java.time.Instant;
+
+/** Parse metadata from inbound email */
+public class MetadataParser {
+  public static MailMetadata parse(MailMessage m) {
+    MailMetadata metadata = new MailMetadata();
+    // Find author
+    metadata.author = m.from().getEmail();
+
+    // Check email headers for X-Gerrit-<Name>
+    for (String header : m.additionalHeaders()) {
+      if (header.startsWith(toHeaderWithDelimiter(MetadataName.CHANGE_ID))) {
+        metadata.changeId = header
+            .substring(toHeaderWithDelimiter(MetadataName.CHANGE_ID).length());
+      } else if (header.startsWith(
+          toHeaderWithDelimiter(MetadataName.PATCH_SET))) {
+        String ps = header.substring(
+            toHeaderWithDelimiter(MetadataName.PATCH_SET).length());
+        metadata.patchSet = Ints.tryParse(ps);
+      } else if (header.startsWith(
+          toHeaderWithDelimiter(MetadataName.TIMESTAMP))) {
+        String ts = header.substring(
+            toHeaderWithDelimiter(MetadataName.TIMESTAMP).length());
+        metadata.timestamp = Timestamp.from(
+            MailUtil.rfcDateformatter.parse(ts, Instant::from));
+      } else if (header.startsWith(
+          toHeaderWithDelimiter(MetadataName.MESSAGE_TYPE))) {
+        metadata.messageType = header.substring(
+            toHeaderWithDelimiter(MetadataName.MESSAGE_TYPE).length());
+      }
+    }
+    if (metadata.hasRequiredFields()) {
+      return metadata;
+    }
+
+    // If the required fields were not yet found, continue to parse the text
+    if (!Strings.isNullOrEmpty(m.textContent())) {
+      String[] lines = m.textContent().split("\n");
+      extractFooters(lines, metadata);
+      if (metadata.hasRequiredFields()) {
+        return metadata;
+      }
+    }
+
+    // If the required fields were not yet found, continue to parse the HTML
+    // HTML footer are contained inside a <p> tag
+    if (!Strings.isNullOrEmpty(m.htmlContent())) {
+      String[] lines = m.htmlContent().split("</p>");
+      extractFooters(lines, metadata);
+      if (metadata.hasRequiredFields()) {
+        return metadata;
+      }
+    }
+
+    return metadata;
+  }
+
+  private static void extractFooters(String[] lines, MailMetadata metadata) {
+    for (String line : lines) {
+      if (metadata.changeId == null && line.contains(MetadataName.CHANGE_ID)) {
+        metadata.changeId =
+            extractFooter(toFooterWithDelimiter(MetadataName.CHANGE_ID), line);
+      } else if (metadata.patchSet == null &&
+          line.contains(MetadataName.PATCH_SET)) {
+        metadata.patchSet = Ints.tryParse(
+            extractFooter(toFooterWithDelimiter(MetadataName.PATCH_SET), line));
+      } else if (metadata.timestamp == null &&
+          line.contains(MetadataName.TIMESTAMP)) {
+        String ts =
+            extractFooter(toFooterWithDelimiter(MetadataName.TIMESTAMP), line);
+        metadata.timestamp = Timestamp.from(
+            MailUtil.rfcDateformatter.parse(ts, Instant::from));
+      } else if (metadata.messageType == null &&
+          line.contains(MetadataName.MESSAGE_TYPE)) {
+        metadata.messageType = extractFooter(
+            toFooterWithDelimiter(MetadataName.MESSAGE_TYPE), line);
+      }
+    }
+  }
+
+  private static String extractFooter(String key, String line) {
+    return line.substring(line.indexOf(key) + key.length(), line.length());
+  }
+}

gerrit-server/src/test/java/com/google/gerrit/server/mail/receive/MetadataParserTest.java

@@ -0,0 +1,121 @@
+// 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 static com.google.gerrit.server.mail.MetadataName.toFooterWithDelimiter;
+import static com.google.gerrit.server.mail.MetadataName.toHeaderWithDelimiter;
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.gerrit.server.mail.Address;
+import com.google.gerrit.server.mail.MetadataName;
+
+import org.joda.time.DateTime;
+import org.joda.time.DateTimeZone;
+import org.junit.Test;
+
+public class MetadataParserTest {
+  @Test
+  public void testParseMetadataFromHeader() {
+    // This tests if the metadata parser is able to parse metadata from the
+    // email headers of the message.
+    MailMessage.Builder b = MailMessage.builder();
+    b.id("");
+    b.dateReceived(new DateTime());
+    b.subject("");
+
+    b.addAdditionalHeader(
+        toHeaderWithDelimiter(MetadataName.CHANGE_ID) + "cid");
+    b.addAdditionalHeader(toHeaderWithDelimiter(MetadataName.PATCH_SET) + "1");
+    b.addAdditionalHeader(
+        toHeaderWithDelimiter(MetadataName.MESSAGE_TYPE) +"comment");
+    b.addAdditionalHeader(toHeaderWithDelimiter(MetadataName.TIMESTAMP) +
+        "Tue, 25 Oct 2016 02:11:35 -0700");
+
+    Address author = new Address("Diffy", "test@gerritcodereview.com");
+    b.from(author);
+
+    MailMetadata meta = MetadataParser.parse(b.build());
+    assertThat(meta.author).isEqualTo(author.getEmail());
+    assertThat(meta.changeId).isEqualTo("cid");
+    assertThat(meta.patchSet).isEqualTo(1);
+    assertThat(meta.messageType).isEqualTo("comment");
+    assertThat(meta.timestamp.getTime()).isEqualTo(
+        new DateTime(2016, 10, 25, 9, 11, 35, 0, DateTimeZone.UTC).getMillis());
+  }
+
+  @Test
+  public void testParseMetadataFromText() {
+    // This tests if the metadata parser is able to parse metadata from the
+    // the text body of the message.
+    MailMessage.Builder b = MailMessage.builder();
+    b.id("");
+    b.dateReceived(new DateTime());
+    b.subject("");
+
+    StringBuilder stringBuilder = new StringBuilder();
+    stringBuilder.append(
+        toFooterWithDelimiter(MetadataName.CHANGE_ID) + "cid" + "\n");
+    stringBuilder.append(
+        toFooterWithDelimiter(MetadataName.PATCH_SET) + "1" + "\n");
+    stringBuilder.append(
+        toFooterWithDelimiter(MetadataName.MESSAGE_TYPE) + "comment" + "\n");
+    stringBuilder.append(toFooterWithDelimiter(MetadataName.TIMESTAMP) +
+        "Tue, 25 Oct 2016 02:11:35 -0700" + "\n");
+    b.textContent(stringBuilder.toString());
+
+    Address author = new Address("Diffy", "test@gerritcodereview.com");
+    b.from(author);
+
+    MailMetadata meta = MetadataParser.parse(b.build());
+    assertThat(meta.author).isEqualTo(author.getEmail());
+    assertThat(meta.changeId).isEqualTo("cid");
+    assertThat(meta.patchSet).isEqualTo(1);
+    assertThat(meta.messageType).isEqualTo("comment");
+    assertThat(meta.timestamp.getTime()).isEqualTo(
+        new DateTime(2016, 10, 25, 9, 11, 35, 0, DateTimeZone.UTC).getMillis());
+  }
+
+  @Test
+  public void testParseMetadataFromHTML() {
+    // This tests if the metadata parser is able to parse metadata from the
+    // the HTML body of the message.
+    MailMessage.Builder b = MailMessage.builder();
+    b.id("");
+    b.dateReceived(new DateTime());
+    b.subject("");
+
+    StringBuilder stringBuilder = new StringBuilder();
+    stringBuilder.append("<p>" +
+        toFooterWithDelimiter(MetadataName.CHANGE_ID) + "cid" + "</p>");
+    stringBuilder.append("<p>" + toFooterWithDelimiter(MetadataName.PATCH_SET) +
+        "1" + "</p>");
+    stringBuilder.append("<p>" +
+        toFooterWithDelimiter(MetadataName.MESSAGE_TYPE) + "comment" + "</p>");
+    stringBuilder.append("<p>" + toFooterWithDelimiter(MetadataName.TIMESTAMP) +
+        "Tue, 25 Oct 2016 02:11:35 -0700" + "</p>");
+    b.htmlContent(stringBuilder.toString());
+
+    Address author = new Address("Diffy", "test@gerritcodereview.com");
+    b.from(author);
+
+    MailMetadata meta = MetadataParser.parse(b.build());
+    assertThat(meta.author).isEqualTo(author.getEmail());
+    assertThat(meta.changeId).isEqualTo("cid");
+    assertThat(meta.patchSet).isEqualTo(1);
+    assertThat(meta.messageType).isEqualTo("comment");
+    assertThat(meta.timestamp.getTime()).isEqualTo(
+        new DateTime(2016, 10, 25, 9, 11, 35, 0, DateTimeZone.UTC).getMillis());
+  }
+}