Gist auto filesharing in help threads

application/config.json.template

@@ -1,5 +1,6 @@
 {
     "token": "<put_your_token_here>",
+    "gistApiKey": "<your_gist_personal_access_token>",
     "databasePath": "local-database.db",
     "projectWebsite": "https://github.com/Together-Java/TJ-Bot",
     "discordGuildInvite": "https://discord.com/invite/XXFUXzK",

application/src/main/java/org/togetherjava/tjbot/commands/Features.java

@@ -2,10 +2,8 @@
 
 import net.dv8tion.jda.api.JDA;
 import org.jetbrains.annotations.NotNull;
-import org.togetherjava.tjbot.commands.basic.PingCommand;
-import org.togetherjava.tjbot.commands.basic.RoleSelectCommand;
-import org.togetherjava.tjbot.commands.basic.SuggestionsUpDownVoter;
-import org.togetherjava.tjbot.commands.basic.VcActivityCommand;
+import org.togetherjava.tjbot.commands.basic.*;
+import org.togetherjava.tjbot.commands.filesharing.FileSharingMessageListener;
 import org.togetherjava.tjbot.commands.help.*;
 import org.togetherjava.tjbot.commands.mathcommands.TeXCommand;
 import org.togetherjava.tjbot.commands.mathcommands.wolframalpha.WolframAlphaCommand;
@@ -81,6 +79,7 @@ public enum Features {
         features.add(new SuggestionsUpDownVoter(config));
         features.add(new ScamBlocker(actionsStore, scamHistoryStore, config));
         features.add(new ImplicitAskListener(config, helpSystemHelper));
+        features.add(new FileSharingMessageListener(config));
 
         // Event receivers
         features.add(new RejoinModerationRoleListener(actionsStore, config));

application/src/main/java/org/togetherjava/tjbot/commands/filesharing/FileSharingMessageListener.java

@@ -0,0 +1,213 @@
+package org.togetherjava.tjbot.commands.filesharing;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import net.dv8tion.jda.api.entities.ChannelType;
+import net.dv8tion.jda.api.entities.Message;
+import net.dv8tion.jda.api.entities.ThreadChannel;
+import net.dv8tion.jda.api.entities.User;
+import net.dv8tion.jda.api.events.message.MessageReceivedEvent;
+import net.dv8tion.jda.api.interactions.components.buttons.Button;
+import org.jetbrains.annotations.NotNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.togetherjava.tjbot.commands.MessageReceiverAdapter;
+import org.togetherjava.tjbot.config.Config;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UncheckedIOException;
+import java.net.HttpURLConnection;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.nio.charset.StandardCharsets;
+import java.util.*;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Predicate;
+import java.util.regex.Pattern;
+
+/**
+ * Listener that receives all sent help messages and uploads them to a share service if the message
+ * contains a file with the given extension in the
+ * {@link FileSharingMessageListener#extensionFilter}.
+ */
+public class FileSharingMessageListener extends MessageReceiverAdapter {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(FileSharingMessageListener.class);
+    private static final ObjectMapper JSON = new ObjectMapper();
+
+    private static final String SHARE_API = "https://api.github.com/gists";
+    private static final HttpClient CLIENT = HttpClient.newHttpClient();
+
+    private final String gistApiKey;
+    private final Set<String> extensionFilter = Set.of("txt", "java", "gradle", "xml", "kt", "json",
+            "fxml", "css", "c", "h", "cpp", "py", "yml");
+
+    private final Predicate<String> isStagingChannelName;
+    private final Predicate<String> isOverviewChannelName;
+
+
+    public FileSharingMessageListener(@NotNull Config config) {
+        super(Pattern.compile(".*"));
+
+        gistApiKey = config.getGistApiKey();
+        isStagingChannelName = Pattern.compile(config.getHelpSystem().getStagingChannelPattern())
+            .asMatchPredicate();
+        isOverviewChannelName = Pattern.compile(config.getHelpSystem().getOverviewChannelPattern())
+            .asMatchPredicate();
+    }
+
+    @Override
+    public void onMessageReceived(@NotNull MessageReceivedEvent event) {
+        User author = event.getAuthor();
+        if (author.isBot() || event.isWebhookMessage()) {
+            return;
+        }
+
+        if (!isHelpThread(event)) {
+            return;
+        }
+
+
+        List<Message.Attachment> attachments = event.getMessage()
+            .getAttachments()
+            .stream()
+            .filter(this::isAttachmentRelevant)
+            .toList();
+
+        CompletableFuture.runAsync(() -> {
+            try {
+                processAttachments(event, attachments);
+            } catch (Exception e) {
+                LOGGER.error("Unknown error while processing attachments", e);
+            }
+        });
+    }
+
+    private boolean isAttachmentRelevant(@NotNull Message.Attachment attachment) {
+        String extension = attachment.getFileExtension();
+        if (extension == null) {
+            return false;
+        }
+        return extensionFilter.contains(extension);
+    }
+
+
+    private void processAttachments(@NotNull MessageReceivedEvent event,
+            @NotNull List<Message.Attachment> attachments) {
+
+        Map<String, GistFile> nameToFile = new ConcurrentHashMap<>();
+
+        List<CompletableFuture<Void>> tasks = new ArrayList<>();
+        for (Message.Attachment attachment : attachments) {
+            CompletableFuture<Void> task = attachment.retrieveInputStream()
+                .thenApply(this::readAttachment)
+                .thenAccept(
+                        content -> nameToFile.put(getNameOf(attachment), new GistFile(content)));
+
+            tasks.add(task);
+        }
+
+        tasks.forEach(CompletableFuture::join);
+
+        GistFiles files = new GistFiles(nameToFile);
+        GistRequest request = new GistRequest(event.getAuthor().getName(), false, files);
+        String url = uploadToGist(request);
+        sendResponse(event, url);
+    }
+
+    private @NotNull String readAttachment(@NotNull InputStream stream) {
+        try {
+            return new String(stream.readAllBytes(), StandardCharsets.UTF_8);
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+
+    private @NotNull String getNameOf(@NotNull Message.Attachment attachment) {
+        String fileName = attachment.getFileName();
+        String fileExtension = attachment.getFileExtension();
+
+        if (fileExtension == null || fileExtension.equals("txt")) {
+            fileExtension = "java";
+        } else if (fileExtension.equals("fxml")) {
+            fileExtension = "xml";
+        }
+
+        int extensionIndex = fileName.lastIndexOf('.');
+        if (extensionIndex != -1) {
+            fileName = fileName.substring(0, extensionIndex);
+        }
+
+        fileName += "." + fileExtension;
+
+        return fileName;
+    }
+
+    private @NotNull String uploadToGist(@NotNull GistRequest jsonRequest) {
+        String body;
+        try {
+            body = JSON.writeValueAsString(jsonRequest);
+        } catch (JsonProcessingException e) {
+            throw new IllegalStateException(
+                    "Attempting to upload a file to gist, but unable to create the JSON request.",
+                    e);
+        }
+
+        HttpRequest request = HttpRequest.newBuilder()
+            .uri(URI.create(SHARE_API))
+            .header("Accept", "application/json")
+            .header("Authorization", "token " + gistApiKey)
+            .POST(HttpRequest.BodyPublishers.ofString(body))
+            .build();
+
+        HttpResponse<String> apiResponse;
+        try {
+            apiResponse = CLIENT.send(request, HttpResponse.BodyHandlers.ofString());
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            throw new IllegalStateException(
+                    "Attempting to upload a file to gist, but the request got interrupted.", e);
+        }
+
+        int statusCode = apiResponse.statusCode();
+
+        if (statusCode < HttpURLConnection.HTTP_OK
+                || statusCode >= HttpURLConnection.HTTP_MULT_CHOICE) {
+            throw new IllegalStateException("Gist API unexpected response: " + apiResponse.body());
+        }
+
+        GistResponse gistResponse;
+        try {
+            gistResponse = JSON.readValue(apiResponse.body(), GistResponse.class);
+        } catch (JsonProcessingException e) {
+            throw new IllegalStateException(
+                    "Attempting to upload file to gist, but unable to parse its JSON response.", e);
+        }
+        return gistResponse.getHtmlUrl();
+    }
+
+    private void sendResponse(@NotNull MessageReceivedEvent event, @NotNull String url) {
+        Message message = event.getMessage();
+        String messageContent =
+                "I uploaded your attachments as **gist**. That way, they are easier to read for everyone, especially mobile users 👍";
+
+        message.reply(messageContent).setActionRow(Button.link(url, "gist")).queue();
+    }
+
+    private boolean isHelpThread(@NotNull MessageReceivedEvent event) {
+        if (event.getChannelType() != ChannelType.GUILD_PUBLIC_THREAD) {
+            return false;
+        }
+
+        ThreadChannel thread = event.getThreadChannel();
+        String rootChannelName = thread.getParentChannel().getName();
+        return isStagingChannelName.test(rootChannelName)
+                || isOverviewChannelName.test(rootChannelName);
+    }
+}

application/src/main/java/org/togetherjava/tjbot/commands/filesharing/GistFile.java

@@ -0,0 +1,10 @@
+package org.togetherjava.tjbot.commands.filesharing;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @see <a href="https://docs.github.com/en/rest/gists/gists#create-a-gist">Create a Gist via
+ *      API</a>
+ */
+record GistFile(@NotNull String content) {
+}

application/src/main/java/org/togetherjava/tjbot/commands/filesharing/GistFiles.java

@@ -0,0 +1,13 @@
+package org.togetherjava.tjbot.commands.filesharing;
+
+import com.fasterxml.jackson.annotation.JsonAnyGetter;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Map;
+
+/**
+ * @see <a href="https://docs.github.com/en/rest/gists/gists#create-a-gist">Create a Gist via
+ *      API</a>
+ */
+record GistFiles(@NotNull @JsonAnyGetter Map<String, GistFile> nameToContent) {
+}

application/src/main/java/org/togetherjava/tjbot/commands/filesharing/GistRequest.java

@@ -0,0 +1,12 @@
+package org.togetherjava.tjbot.commands.filesharing;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @see <a href="https://docs.github.com/en/rest/gists/gists#create-a-gist">Create a Gist via
+ *      API</a>
+ */
+record GistRequest(@NotNull String description, @JsonProperty("public") boolean isPublic,
+        @NotNull GistFiles files) {
+}

application/src/main/java/org/togetherjava/tjbot/commands/filesharing/GistResponse.java

@@ -0,0 +1,23 @@
+package org.togetherjava.tjbot.commands.filesharing;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * @see <a href="https://docs.github.com/en/rest/gists/gists#create-a-gist">Create a Gist via
+ *      API</a>
+ */
+@JsonIgnoreProperties(ignoreUnknown = true)
+final class GistResponse {
+    @JsonProperty("html_url")
+    private String htmlUrl;
+
+    public @NotNull String getHtmlUrl() {
+        return this.htmlUrl;
+    }
+
+    public void setHtmlUrl(@NotNull String htmlUrl) {
+        this.htmlUrl = htmlUrl;
+    }
+}

application/src/main/java/org/togetherjava/tjbot/commands/filesharing/package-info.java

@@ -0,0 +1,5 @@
+/**
+ * This package offers all the functionality for automatically uploading files to sharing services.
+ * The core class is {@link org.togetherjava.tjbot.commands.filesharing.FileSharingMessageListener}.
+ */
+package org.togetherjava.tjbot.commands.filesharing;

application/src/main/java/org/togetherjava/tjbot/config/Config.java

@@ -14,6 +14,7 @@
  */
 public final class Config {
     private final String token;
+    private final String gistApiKey;
     private final String databasePath;
     private final String projectWebsite;
     private final String discordGuildInvite;
@@ -31,6 +32,7 @@ public final class Config {
     @SuppressWarnings("ConstructorWithTooManyParameters")
     @JsonCreator(mode = JsonCreator.Mode.PROPERTIES)
     private Config(@JsonProperty("token") String token,
+            @JsonProperty("gistApiKey") String gistApiKey,
             @JsonProperty("databasePath") String databasePath,
             @JsonProperty("projectWebsite") String projectWebsite,
             @JsonProperty("discordGuildInvite") String discordGuildInvite,
@@ -45,6 +47,7 @@ private Config(@JsonProperty("token") String token,
             @JsonProperty("wolframAlphaAppId") String wolframAlphaAppId,
             @JsonProperty("helpSystem") HelpSystemConfig helpSystem) {
         this.token = token;
+        this.gistApiKey = gistApiKey;
         this.databasePath = databasePath;
         this.projectWebsite = projectWebsite;
         this.discordGuildInvite = discordGuildInvite;
@@ -100,6 +103,18 @@ public String getToken() {
         return token;
     }
 
+    /**
+     * Gets the API Key of GitHub to upload pastes via the API.
+     *
+     * @return the upload services API Key
+     * @see <a href=
+     *      "https://docs.github.com/en/enterprise-server@3.4/authentication/keeping-your-account-and-data-secure/creating-a-personal-access-token">Create
+     *      a GitHub key</a>
+     */
+    public String getGistApiKey() {
+        return gistApiKey;
+    }
+
     /**
      * Gets the path where the database of the application is located at.
      *