Add public share results feature

src/main/java/tfb/status/bootstrap/ServicesBinder.java

@@ -35,6 +35,7 @@
 import tfb.status.service.ObjectMapperFactory;
 import tfb.status.service.RunCompleteMailer;
 import tfb.status.service.RunProgressMonitor;
+import tfb.status.service.ShareResultsMailer;
 import tfb.status.service.ShareResultsUploader;
 import tfb.status.service.TaskScheduler;
 import tfb.status.service.TickerFactory;
@@ -79,6 +80,7 @@ protected void configure() {
     addActiveDescriptor(RunCompleteMailer.class);
     addActiveDescriptor(TaskScheduler.class);
     addActiveDescriptor(ShareResultsUploader.class);
+    addActiveDescriptor(ShareResultsMailer.class);
     addActiveDescriptor(RootHandler.class);
     addActiveDescriptor(HomePageHandler.class);
     addActiveDescriptor(HomeUpdatesHandler.class);

src/main/java/tfb/status/config/ApplicationConfig.java

@@ -58,6 +58,12 @@ public final class ApplicationConfig {
   @Provides
   public final UrlsConfig urlsConfig;
 
+  /**
+   * See {@link ShareResultsMailerConfig}
+   */
+  @Provides
+  public final ShareResultsMailerConfig shareResultsMailer;
+
   /**
    * The configuration for outbound emails, or {@code null} if outbound emails
    * are disabled.  See {@link EmailConfig}.
@@ -81,7 +87,8 @@ public ApplicationConfig(HttpServerConfig http,
                            RunProgressMonitorConfig runProgressMonitor,
                            RunCompleteMailerConfig runCompleteMailer,
                            @Nullable EmailConfig email,
-                           UrlsConfig urlsConfig) {
+                           UrlsConfig urlsConfig,
+                           ShareResultsMailerConfig shareResultsMailer) {
 
     this.http = Objects.requireNonNull(http);
     this.assets = Objects.requireNonNull(assets);
@@ -91,6 +98,7 @@ public ApplicationConfig(HttpServerConfig http,
     this.runCompleteMailer = Objects.requireNonNull(runCompleteMailer);
     this.email = email;
     this.urlsConfig = Objects.requireNonNull(urlsConfig);
+    this.shareResultsMailer = Objects.requireNonNull(shareResultsMailer);
   }
 
   @Override
@@ -150,7 +158,10 @@ public static ApplicationConfig create(
       @Nullable EmailConfig email,
 
       @JsonProperty(value = "urls", required = false)
-      @Nullable UrlsConfig urls) {
+      @Nullable UrlsConfig urls,
+
+      @JsonProperty(value = "shareResultsMailer", required = false)
+      @Nullable ShareResultsMailerConfig shareResultsMailer) {
 
     return new ApplicationConfig(
         /* http= */
@@ -189,10 +200,15 @@ public static ApplicationConfig create(
         /* urlsConfig= */
         Objects.requireNonNullElseGet(
             urls,
-            () -> UrlsConfig.defaultConfig()));
+            () -> UrlsConfig.defaultConfig()),
+
+        /* shareResultsMailer= */
+        Objects.requireNonNullElseGet(
+            shareResultsMailer,
+            () -> ShareResultsMailerConfig.defaultConfig()));
   }
 
   public static ApplicationConfig defaultConfig() {
-    return create(null, null, null, null, null, null, null, null);
+    return create(null, null, null, null, null, null, null, null, null);
   }
 }

src/main/java/tfb/status/config/ShareResultsMailerConfig.java

@@ -0,0 +1,69 @@
+package tfb.status.config;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.errorprone.annotations.Immutable;
+import java.time.Duration;
+import java.util.Objects;
+import javax.inject.Singleton;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+/**
+ * The configuration for the service that sends an emails related to sharing.
+ */
+@Immutable
+@Singleton
+public class ShareResultsMailerConfig {
+  /**
+   * The minimum number of seconds that must pass after sending one email before
+   * sending another. This is used to prevent accidental self-spam if there are
+   * a lot of requests to upload results when the share directory is full.
+   */
+  public final long minSecondsBetweenDirectoryFullEmails;
+
+  public ShareResultsMailerConfig(long minSecondsBetweenDirectoryFullEmails) {
+    this.minSecondsBetweenDirectoryFullEmails =
+        minSecondsBetweenDirectoryFullEmails;
+  }
+
+  @Override
+  public boolean equals(@Nullable Object object) {
+    if (object == this) {
+      return true;
+    } else if (!(object instanceof ShareResultsMailerConfig)) {
+      return false;
+    } else {
+      ShareResultsMailerConfig that = (ShareResultsMailerConfig) object;
+      return this.minSecondsBetweenDirectoryFullEmails ==
+          that.minSecondsBetweenDirectoryFullEmails;
+    }
+  }
+
+  @Override
+  public int hashCode() {
+    int hash = 1;
+    hash = 31 * hash + Long.hashCode(minSecondsBetweenDirectoryFullEmails);
+    return hash;
+  }
+
+  @JsonCreator
+  public static ShareResultsMailerConfig create(
+      @JsonProperty(
+          value = "minSecondsBetweenDirectoryFullEmails",
+          required = false)
+      @Nullable Long minSecondsBetweenDirectoryFullEmails) {
+
+    return new ShareResultsMailerConfig(
+        /* minSecondsBetweenDirectoryFullEmails= */
+        Objects.requireNonNullElse(
+            minSecondsBetweenDirectoryFullEmails,
+            DEFAULT_MIN_SECONDS_BETWEEN_DIRECTORY_FULL_EMAILS));
+  }
+
+  public static ShareResultsMailerConfig defaultConfig() {
+    return create(null);
+  }
+
+  private static final long DEFAULT_MIN_SECONDS_BETWEEN_DIRECTORY_FULL_EMAILS =
+      Duration.ofDays(1).toSeconds();
+}

src/main/java/tfb/status/service/ShareResultsMailer.java

@@ -0,0 +1,97 @@
+package tfb.status.service;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.collect.ImmutableList;
+import com.google.errorprone.annotations.concurrent.GuardedBy;
+import java.time.Clock;
+import java.time.Instant;
+import java.util.Objects;
+import javax.inject.Inject;
+import javax.inject.Singleton;
+import javax.mail.MessagingException;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import tfb.status.config.ShareResultsMailerConfig;
+
+@Singleton
+public final class ShareResultsMailer {
+  private final Logger logger = LoggerFactory.getLogger(getClass());
+  private final Clock clock;
+  private final EmailSender emailSender;
+  private final ShareResultsMailerConfig config;
+
+  @GuardedBy("emailTimeLock")
+  private volatile @Nullable Instant previousEmailTime;
+  private final Object emailTimeLock = new Object();
+
+  @Inject
+  public ShareResultsMailer(Clock clock,
+                            EmailSender emailSender,
+                            ShareResultsMailerConfig config) {
+    this.clock = Objects.requireNonNull(clock);
+    this.emailSender = Objects.requireNonNull(emailSender);
+    this.config = Objects.requireNonNull(config);
+  }
+
+  public void onShareDirectoryFull(long capacityBytes, long sizeBytes) {
+    synchronized (emailTimeLock) {
+      Instant now = clock.instant();
+      Instant previous = this.previousEmailTime;
+
+      if (previous != null) {
+        Instant nextEmailTime =
+            previous.plusSeconds(config.minSecondsBetweenDirectoryFullEmails);
+
+        if (now.isBefore(nextEmailTime)) {
+          logger.warn(
+              "Suppressing email for full share directory, "
+                  + "another email was sent for that account too recently, "
+                  + "previous email time = {}, next possible email time = {}",
+              previous,
+              nextEmailTime);
+          return;
+        }
+      }
+
+      this.previousEmailTime = now;
+    }
+
+    sendShareDirectoryFullEmail(capacityBytes, sizeBytes);
+  }
+
+  private void sendShareDirectoryFullEmail(long capacityBytes, long sizeBytes) {
+    try {
+      emailSender.sendEmail(
+          /* subject= */ SHARE_DIRECTORY_FULL_SUBJECT,
+          /* textContent= */
+          composeShareDirectoryFullEmail(capacityBytes, sizeBytes),
+          /* attachments= */ ImmutableList.of());
+    } catch (MessagingException e) {
+      logger.warn("Error sending email for share directory full", e);
+    }
+  }
+
+  private String composeShareDirectoryFullEmail(long capacityBytes,
+                                                long sizeBytes) {
+    return "Hello,"
+        + "\n"
+        + "\n"
+        + "The share directory used for storing public uploads of "
+        + "results files has reached capacity. Please audit the "
+        + "directory and delete old uploads or expand the configured "
+        + "capacity."
+        + "\n"
+        + "\n"
+        + "Share directory capacity: " + capacityBytes + " bytes"
+        + "\n"
+        + "Share directory size:     " + sizeBytes + " bytes"
+        + "\n"
+        + "\n"
+        + "-a robot";
+  }
+
+  @VisibleForTesting
+  public static final String SHARE_DIRECTORY_FULL_SUBJECT =
+      "<tfb> <auto> Share directory full";
+}

src/main/java/tfb/status/service/ShareResultsUploader.java

@@ -48,16 +48,19 @@ public final class ShareResultsUploader {
   private final UrlsConfig urlsConfig;
   private final FileStore fileStore;
   private final ObjectMapper objectMapper;
+  private final ShareResultsMailer shareResultsMailer;
 
   @Inject
   public ShareResultsUploader(FileStoreConfig fileStoreConfig,
                               UrlsConfig urlsConfig,
                               FileStore fileStore,
-                              ObjectMapper objectMapper) {
+                              ObjectMapper objectMapper,
+                              ShareResultsMailer shareResultsMailer) {
     this.fileStoreConfig = Objects.requireNonNull(fileStoreConfig);
     this.urlsConfig = Objects.requireNonNull(urlsConfig);
     this.fileStore = Objects.requireNonNull(fileStore);
     this.objectMapper = Objects.requireNonNull(objectMapper);
+    this.shareResultsMailer = Objects.requireNonNull(shareResultsMailer);
   }
 
   /**
@@ -191,6 +194,8 @@ public ShareResultsUploadReport upload(Path tempFile) throws IOException {
     long shareDirectorySize = FileUtils.directorySizeBytes(
         fileStore.shareDirectory());
     if (shareDirectorySize >= fileStoreConfig.maxShareDirectorySizeBytes) {
+      shareResultsMailer.onShareDirectoryFull(
+          fileStoreConfig.maxShareDirectorySizeBytes, shareDirectorySize);
       return "Share uploads has reached max capacity.";
     }
 

src/test/java/tfb/status/service/ShareResultsMailerTest.java

@@ -0,0 +1,51 @@
+package tfb.status.service;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import com.google.common.collect.ImmutableList;
+import java.io.IOException;
+import java.util.List;
+import javax.mail.MessagingException;
+import javax.mail.internet.MimeMessage;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import tfb.status.testlib.MailServer;
+import tfb.status.testlib.TestServicesInjector;
+
+/**
+ * Tests for {@link ShareResultsMailer}.
+ */
+@ExtendWith(TestServicesInjector.class)
+public final class ShareResultsMailerTest {
+  /**
+   * Verifies that the mailer sends an email with the expected title when the
+   * {@link ShareResultsMailer#onShareDirectoryFull(long, long)} method is
+   * invoked.
+   */
+  @Test
+  public void shareResultsMailer_shareDirectoryFullEmail(
+      MailServer mailServer,
+      ShareResultsMailer shareResultsMailer)
+      throws IOException, MessagingException {
+
+    // The mailer is a singleton and may have been called by other tests
+    // indirectly. We just need to make sure it sent an email as a result of
+    // this test.
+    List<MimeMessage> messages =getShareDirectoryFullEmails(mailServer);
+    int initialMessagesSize = messages.size();
+
+    shareResultsMailer.onShareDirectoryFull(1234, 5678);
+
+    messages = getShareDirectoryFullEmails(mailServer);
+
+    assertEquals(initialMessagesSize + 1, messages.size());
+  }
+
+  private static ImmutableList<MimeMessage> getShareDirectoryFullEmails(
+      MailServer mailServer) throws IOException, MessagingException {
+
+    return mailServer.getMessages(
+        m -> m.getSubject().equals(
+            ShareResultsMailer.SHARE_DIRECTORY_FULL_SUBJECT));
+  }
+}

src/test/resources/test_config.yml

@@ -32,3 +32,6 @@ runCompleteMailer:
 urls:
   tfbStatus: https://test.tfb-status.techempower.com
   teWeb: https://www.test.techempower.com
+
+shareResultsMailer:
+  minSecondsBetweenDirectoryFullEmails: 0