src/main/java/se/su/dsv/whisperapi/JDBCTranscriptionRepository.java

@@ -6,6 +6,7 @@ import se.su.dsv.whisperapi.core.Job;
 import se.su.dsv.whisperapi.core.JobCompletion;
 import se.su.dsv.whisperapi.core.NotificationStatus;
 import se.su.dsv.whisperapi.core.OutputFormat;
+import se.su.dsv.whisperapi.core.SourceFile;
 import se.su.dsv.whisperapi.core.TranscriptionRepository;
 import se.su.dsv.whisperapi.core.Transcription;
 
@@ -55,14 +56,16 @@ public class JDBCTranscriptionRepository implements TranscriptionRepository {
     }
 
     @Override
-    public void addFileToTranscription(Transcription transcription, String filename) {
+    public void addFileToTranscription(Transcription transcription, SourceFile sourceFile) {
         jdbcClient.sql("""
-                INSERT INTO transcriptions_files (transcription_id, filename)
+                INSERT INTO transcriptions_files (id, transcription_id, filename, transcribed_result_uri)
-                VALUES (:transcription_id, :filename)
+                VALUES (:id, :transcription_id, :filename, :result_file_download_uri)
                 ON DUPLICATE KEY UPDATE filename = :filename
                 """)
                 .param("transcription_id", transcription.id())
-                .param("filename", filename)
+                .param("id", sourceFile.id())
+                .param("filename", sourceFile.filename())
+                .param("result_file_download_uri", sourceFile.downloadUri().toString())
                 .update();
     }
 

src/main/java/se/su/dsv/whisperapi/api/ApiController.java

@@ -1,6 +1,8 @@
 package se.su.dsv.whisperapi.api;
 
+import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.PutMapping;
@@ -15,7 +17,7 @@ import se.su.dsv.whisperapi.core.JobCompletion;
 import se.su.dsv.whisperapi.core.JobNotFound;
 import se.su.dsv.whisperapi.core.OutputFormat;
 import se.su.dsv.whisperapi.core.Transcription;
-import se.su.dsv.whisperapi.core.TranscriptionFile;
+import se.su.dsv.whisperapi.core.SourceFileUpload;
 import se.su.dsv.whisperapi.core.TranscriptionService;
 
 import java.io.IOException;
@@ -78,6 +80,7 @@ public class ApiController {
             Principal owner,
             @PathVariable("id") String id,
             @RequestHeader("X-Filename") String filename,
+            UriComponentsBuilder uriComponentsBuilder,
             InputStream fileData)
     {
         try {
@@ -87,7 +90,22 @@ public class ApiController {
             UUID uuid = UUID.fromString(id);
             Transcription transcription = transcriptionService.getTranscription(owner, uuid)
                     .orElseThrow(() -> new TranscriptionNotFound(id));
-            transcriptionService.addFileToBeTranscribed(transcription, new TranscriptionFile(filename, fileData));
+            transcriptionService.addFileToBeTranscribed(
+                    transcription,
+                    new SourceFileUpload(filename, fileData),
+                    // The URI is generated here at upload since we need to be in a web context to generate it.
+                    // It is likely that the source who uploaded is the same as who will download the result
+                    // so using this as the web context seem like the best spot, the other option would be at
+                    // submission time.
+                    transcribedFileId -> uriComponentsBuilder.cloneBuilder()
+                            .pathSegment("api")
+                            .pathSegment("transcriptions")
+                            .pathSegment(id)
+                            .pathSegment("file")
+                            .pathSegment(transcribedFileId.toString())
+                            .pathSegment("result")
+                            .build()
+                            .toUri());
             return ResponseEntity.accepted().build();
         } catch (IllegalArgumentException ignored) {
             // Invalid UUID
@@ -98,6 +116,30 @@ public class ApiController {
         }
     }
 
+    /**
+     * Get the transcribed result for a given source file if it was transcribed successfully.
+     *
+     * @param owner owner of the transcription job
+     * @param transcriptionId id of the transcription job
+     * @param fileId id of the source file
+     * @return the transcribed result
+     */
+    @GetMapping(value = "/api/transcriptions/{transcriptionId}/file/{fileId}/result",
+                consumes = MediaType.ALL_VALUE,
+                produces = MediaType.APPLICATION_OCTET_STREAM_VALUE)
+    public InputStream getTranscribedResult(
+            Principal owner,
+            @PathVariable("transcriptionId") String transcriptionId,
+            @PathVariable("fileId") String fileId)
+    {
+        // access control
+        transcriptionService.getTranscription(owner, UUID.fromString(transcriptionId))
+                .orElseThrow(() -> new TranscriptionNotFound(transcriptionId));
+
+        // todo
+        throw new UnsupportedOperationException("NYI");
+    }
+
     @PostMapping(value = "/api/transcriptions/{id}/job", consumes = "*/*")
     public ResponseEntity<Void> submitTranscriptionJob(
             Principal owner,

src/main/java/se/su/dsv/whisperapi/core/Callback.java

@@ -0,0 +1,29 @@
+package se.su.dsv.whisperapi.core;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonSubTypes;
+import com.fasterxml.jackson.annotation.JsonTypeInfo;
+
+import java.util.List;
+import java.util.UUID;
+
+public record Callback(
+        @JsonProperty("transcription_id") UUID transcriptionId,
+        @JsonProperty("files") List<File> files)
+{
+    @JsonTypeInfo(use = JsonTypeInfo.Id.NAME, property = "result")
+    @JsonSubTypes({
+            @JsonSubTypes.Type(value = File.Transcribed.class, name = "success"),
+            @JsonSubTypes.Type(value = File.Failed.class, name = "failure")
+    })
+    sealed interface File {
+        record Transcribed(
+                @JsonProperty("original_file_name") String originalFilename,
+                @JsonProperty("transcription_download_link") String transcriptionDownloadLink)
+                implements File {}
+        record Failed(
+                @JsonProperty("original_file_name") String originalFilename,
+                @JsonProperty("error_message") String errorMessage)
+                implements File {}
+    }
+}

src/main/java/se/su/dsv/whisperapi/core/SourceFile.java

@@ -0,0 +1,11 @@
+package se.su.dsv.whisperapi.core;
+
+import java.net.URI;
+import java.util.UUID;
+
+/**
+ * @param filename the user provided file name
+ * @param downloadUri a pre-generated download link for any potential future transcription result
+ */
+public record SourceFile(UUID id, String filename, URI downloadUri) {
+}

src/main/java/se/su/dsv/whisperapi/core/SourceFileUpload.java

@@ -0,0 +1,6 @@
+package se.su.dsv.whisperapi.core;
+
+import java.io.InputStream;
+
+public record SourceFileUpload(String filename, InputStream data) {
+}

src/main/java/se/su/dsv/whisperapi/core/TranscribedFileDownloadUriGenerator.java

@@ -0,0 +1,9 @@
+package se.su.dsv.whisperapi.core;
+
+import java.net.URI;
+import java.util.UUID;
+
+@FunctionalInterface
+public interface TranscribedFileDownloadUriGenerator {
+    URI generateDownloadUri(UUID transcribedFileId);
+}

src/main/java/se/su/dsv/whisperapi/core/TranscriptionFile.java

@@ -1,6 +0,0 @@
-package se.su.dsv.whisperapi.core;
-
-import java.io.InputStream;
-
-public record TranscriptionFile(String filename, InputStream data) {
-}

src/main/java/se/su/dsv/whisperapi/core/TranscriptionRepository.java

@@ -11,7 +11,7 @@ public interface TranscriptionRepository {
 
     Optional<Transcription> findByOwnerAndId(Principal owner, UUID uuid);
 
-    void addFileToTranscription(Transcription transcription, String filename);
+    void addFileToTranscription(Transcription transcription, SourceFile sourceFile);
 
     /**
      * @return the list of filenames that have been {@link #addFileToTranscription added}

src/main/java/se/su/dsv/whisperapi/core/TranscriptionService.java

@@ -50,16 +50,22 @@ public class TranscriptionService {
         return transcriptionRepository.findByOwnerAndId(owner, uuid);
     }
 
-    public void addFileToBeTranscribed(Transcription transcription, TranscriptionFile file)
+    public void addFileToBeTranscribed(
+            Transcription transcription,
+            SourceFileUpload file,
+            TranscribedFileDownloadUriGenerator downloadUriGenerator)
             throws IOException
     {
-        Path fileToBeTranscribed = fileDirectory.resolve(transcription.id().toString()).resolve(file.filename());
+        UUID uuid = UUID.randomUUID();
+        URI downloadUri = downloadUriGenerator.generateDownloadUri(uuid);
+        Path fileToBeTranscribed = fileDirectory.resolve(transcription.id().toString()).resolve(uuid.toString());
         Files.createDirectories(fileToBeTranscribed.getParent());
         try (var out = Files.newOutputStream(fileToBeTranscribed, StandardOpenOption.CREATE, StandardOpenOption.TRUNCATE_EXISTING);
              var in = file.data())
         {
             in.transferTo(out);
-            transcriptionRepository.addFileToTranscription(transcription, file.filename());
+            SourceFile sourceFile = new SourceFile(uuid, file.filename(), downloadUri);
+            transcriptionRepository.addFileToTranscription(transcription, sourceFile);
         }
     }
 
@@ -150,6 +156,21 @@ public class TranscriptionService {
 
     private boolean notifyOwner(final Transcription transcription, List<Job> jobs) {
         URI callbackUri = transcription.callbackUri();
+        List<Callback.File> files = jobs.stream()
+                .<Callback.File>map(job -> {
+                    switch (job.status()) {
+                        case Job.Status.Completed(JobCompletion.Success ignored) -> {
+                            return new Callback.File.Transcribed("<unknown>", "http://"); //job.transcribedDownloadLink());
+                        }
+                        case Job.Status.Completed(JobCompletion.Failure(String errorMessage)) -> {
+                            return new Callback.File.Failed("<unknown>", errorMessage);
+                        }
+                        case Job.Status.Pending() -> throw new IllegalStateException("Job should be completed");
+                    }
+                })
+                .toList();
+        Callback callback = new Callback(transcription.id(), files);
+        ObjectMapper objectMapper = new ObjectMapper();
         try (HttpClient client = HttpClient.newHttpClient()) {
             HttpRequest request = HttpRequest.newBuilder()
                     .uri(callbackUri)

src/main/resources/db/migration/V5__download_uri_for_transcribed_result.sql

@@ -0,0 +1,7 @@
+ALTER TABLE transcriptions_files
+    ADD COLUMN id UUID NOT NULL FIRST,
+    ADD COLUMN transcribed_result_uri VARCHAR(255) NOT NULL AFTER filename;
+
+ALTER TABLE transcriptions_files ADD INDEX FK_transcriptions_files_transcription (transcription_id);
+ALTER TABLE transcriptions_files DROP PRIMARY KEY;
+ALTER TABLE transcriptions_files ADD PRIMARY KEY (id);