M5 AP-002 Externen Prompt geladen und deterministische KI-Anfrage

aufgebaut
2026-04-07 00:02:20 +02:00
parent c15fb6b18d
commit cd5b6253df
7 changed files with 654 additions and 0 deletions
@@ -0,0 +1,97 @@
+package de.gecheckt.pdf.umbenenner.adapter.out.prompt;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Objects;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import de.gecheckt.pdf.umbenenner.application.port.out.PromptLoadingFailure;
+import de.gecheckt.pdf.umbenenner.application.port.out.PromptLoadingResult;
+import de.gecheckt.pdf.umbenenner.application.port.out.PromptLoadingSuccess;
+import de.gecheckt.pdf.umbenenner.application.port.out.PromptPort;
+import de.gecheckt.pdf.umbenenner.domain.model.PromptIdentifier;
+
+/**
+ * Filesystem-based implementation of {@link PromptPort}.
+ * <p>
+ * Loads prompt templates from an external file on disk and derives a stable identifier
+ * from the filename. Ensures that empty or technically unusable prompts are rejected.
+ * <p>
+ * <strong>Identifier derivation:</strong>
+ * The stable prompt identifier is derived from the filename of the prompt file.
+ * This ensures deterministic, reproducible identification across batch runs.
+ * For example, a prompt file named {@code "prompt_de_v2.txt"} receives the identifier
+ * {@code "prompt_de_v2.txt"}.
+ * <p>
+ * <strong>Content validation:</strong>
+ * After loading, the prompt content is trimmed and validated to ensure it is not empty.
+ * An empty prompt (or one containing only whitespace) is considered technically unusable
+ * and results in a {@link PromptLoadingFailure}.
+ * <p>
+ * <strong>Error handling:</strong>
+ * All technical failures (file not found, I/O errors, permission issues) are caught
+ * and returned as {@link PromptLoadingFailure} rather than thrown as exceptions.
+ */
+public class FilesystemPromptPortAdapter implements PromptPort {
+
+    private static final Logger LOG = LogManager.getLogger(FilesystemPromptPortAdapter.class);
+
+    private final Path promptFilePath;
+
+    /**
+     * Creates the adapter with the configured prompt file path.
+     *
+     * @param promptFilePath the path to the prompt template file; must not be null
+     * @throws NullPointerException if promptFilePath is null
+     */
+    public FilesystemPromptPortAdapter(Path promptFilePath) {
+        this.promptFilePath = Objects.requireNonNull(promptFilePath, "promptFilePath must not be null");
+    }
+
+    @Override
+    public PromptLoadingResult loadPrompt() {
+        try {
+            if (!Files.exists(promptFilePath)) {
+                return new PromptLoadingFailure(
+                        "FILE_NOT_FOUND",
+                        "Prompt file not found at: " + promptFilePath);
+            }
+
+            String content = Files.readString(promptFilePath, StandardCharsets.UTF_8);
+            String trimmedContent = content.trim();
+
+            if (trimmedContent.isEmpty()) {
+                return new PromptLoadingFailure(
+                        "EMPTY_CONTENT",
+                        "Prompt file is empty or contains only whitespace: " + promptFilePath);
+            }
+
+            PromptIdentifier identifier = deriveIdentifier();
+            LOG.debug("Prompt loaded successfully from {}", promptFilePath);
+            return new PromptLoadingSuccess(identifier, trimmedContent);
+
+        } catch (IOException e) {
+            LOG.error("Failed to load prompt file: {}", promptFilePath, e);
+            return new PromptLoadingFailure(
+                    "IO_ERROR",
+                    "Failed to read prompt file: " + e.getMessage());
+        }
+    }
+
+    /**
+     * Derives a stable prompt identifier from the filename.
+     * <p>
+     * The identifier is simply the filename (without the directory path).
+     * This ensures that the same prompt file always receives the same identifier.
+     *
+     * @return a stable PromptIdentifier based on the filename
+     */
+    private PromptIdentifier deriveIdentifier() {
+        String filename = promptFilePath.getFileName().toString();
+        return new PromptIdentifier(filename);
+    }
+}
@@ -0,0 +1,11 @@
+/**
+ * Adapters for external prompt template loading.
+ * <p>
+ * This package provides concrete implementations of the {@link de.gecheckt.pdf.umbenenner.application.port.out.PromptPort}
+ * interface. These adapters handle all technical details of locating, loading, and validating prompt templates
+ * from external sources (typically filesystem files).
+ * <p>
+ * Prompt files are never embedded in code. They are loaded at runtime, assigned stable identifiers for
+ * traceability, and validated to ensure they are not empty or technically unusable.
+ */
+package de.gecheckt.pdf.umbenenner.adapter.out.prompt;