Fixes Throw error for unbuilt engine #81

src/SIL.Machine.AspNetCore/Services/ServalTranslationEngineServiceV1.cs

@@ -37,12 +37,21 @@ public override async Task<Empty> Delete(DeleteRequest request, ServerCallContex
     public override async Task<TranslateResponse> Translate(TranslateRequest request, ServerCallContext context)
     {
         ITranslationEngineService engineService = GetEngineService(request.EngineType);
-        IEnumerable<Translation.TranslationResult> results = await engineService.TranslateAsync(
-            request.EngineId,
-            request.N,
-            request.Segment,
-            context.CancellationToken
-        );
+        IEnumerable<Translation.TranslationResult> results;
+        try
+        {
+            results = await engineService.TranslateAsync(
+                request.EngineId,
+                request.N,
+                request.Segment,
+                context.CancellationToken
+            );
+        }
+        catch (EngineNotBuiltException e)
+        {
+            throw new RpcException(new Status(StatusCode.Aborted, e.Message));
+        }
+
         return new TranslateResponse { Results = { results.Select(Map) } };
     }
 
@@ -52,11 +61,19 @@ ServerCallContext context
     )
     {
         ITranslationEngineService engineService = GetEngineService(request.EngineType);
-        Translation.WordGraph wordGraph = await engineService.GetWordGraphAsync(
-            request.EngineId,
-            request.Segment,
-            context.CancellationToken
-        );
+        Translation.WordGraph wordGraph;
+        try
+        {
+            wordGraph = await engineService.GetWordGraphAsync(
+                request.EngineId,
+                request.Segment,
+                context.CancellationToken
+            );
+        }
+        catch (EngineNotBuiltException e)
+        {
+            throw new RpcException(new Status(StatusCode.Aborted, e.Message));
+        }
         return new GetWordGraphResponse { WordGraph = Map(wordGraph) };
     }
 

src/SIL.Machine.AspNetCore/Services/SmtTransferEngineService.cs

@@ -70,7 +70,7 @@ public override async Task<IReadOnlyList<TranslationResult>> TranslateAsync(
         IDistributedReaderWriterLock @lock = await LockFactory.CreateAsync(engineId, cancellationToken);
         await using (await @lock.ReaderLockAsync(cancellationToken: cancellationToken))
         {
-            TranslationEngine engine = await GetEngineAsync(engineId, cancellationToken);
+            TranslationEngine engine = await GetBuiltEngineAsync(engineId, cancellationToken);
             HybridTranslationEngine hybridEngine = await state.GetHybridEngineAsync(engine.BuildRevision);
             IReadOnlyList<TranslationResult> results = await hybridEngine.TranslateAsync(n, segment, cancellationToken);
             state.LastUsedTime = DateTime.Now;
@@ -88,7 +88,7 @@ public override async Task<WordGraph> GetWordGraphAsync(
         IDistributedReaderWriterLock @lock = await LockFactory.CreateAsync(engineId, cancellationToken);
         await using (await @lock.ReaderLockAsync(cancellationToken: cancellationToken))
         {
-            TranslationEngine engine = await GetEngineAsync(engineId, cancellationToken);
+            TranslationEngine engine = await GetBuiltEngineAsync(engineId, cancellationToken);
             HybridTranslationEngine hybridEngine = await state.GetHybridEngineAsync(engine.BuildRevision);
             WordGraph result = await hybridEngine.GetWordGraphAsync(segment, cancellationToken);
             state.LastUsedTime = DateTime.Now;
@@ -170,12 +170,4 @@ IReadOnlyList<Corpus> corpora
         // Token "None" is used here because hangfire injects the proper cancellation token
         return r => r.RunAsync(engineId, buildId, corpora, CancellationToken.None);
     }
-
-    private async Task<TranslationEngine> GetEngineAsync(string engineId, CancellationToken cancellationToken)
-    {
-        TranslationEngine? engine = await Engines.GetAsync(e => e.EngineId == engineId, cancellationToken);
-        if (engine is null)
-            throw new InvalidOperationException("");
-        return engine;
-    }
 }

src/SIL.Machine.AspNetCore/Services/TranslationEngineServiceBase.cs

@@ -209,4 +209,20 @@ CancellationToken cancellationToken
         }
         return false;
     }
+
+    protected async Task<TranslationEngine> GetEngineAsync(string engineId, CancellationToken cancellationToken)
+    {
+        TranslationEngine? engine = await Engines.GetAsync(e => e.EngineId == engineId, cancellationToken);
+        if (engine is null)
+            throw new InvalidOperationException($"Engine with id {engineId} does not exist");
+        return engine;
+    }
+
+    protected async Task<TranslationEngine> GetBuiltEngineAsync(string engineId, CancellationToken cancellationToken)
+    {
+        TranslationEngine engine = await GetEngineAsync(engineId, cancellationToken);
+        if (engine.BuildState != BuildState.None || engine.BuildRevision == 0)
+            throw new EngineNotBuiltException("The engine must be built first");
+        return engine;
+    }
 }

src/SIL.Machine.AspNetCore/Utils/EngineNotBuiltException.cs

@@ -0,0 +1,9 @@
+namespace SIL.Machine.AspNetCore.Utils
+{
+    /// </summary> This exception is thrown when an unbuilt engine is requested to perform an action that requires it being built <summary>
+    public class EngineNotBuiltException : Exception
+    {
+        public EngineNotBuiltException(string message)
+            : base(message) { }
+    }
+}