Add logit bias parameter to CompletionRequest (#41)

api/src/main/java/com/theokanning/openai/completion/CompletionRequest.java

@@ -6,6 +6,7 @@ import lombok.Data;
 import lombok.NoArgsConstructor;
 
 import java.util.List;
+import java.util.Map;
 
 /**
  * A request for OpenAi to generate a predicted completion for a prompt.
@@ -110,6 +111,15 @@ public class CompletionRequest {
      */
     Integer bestOf;
 
+    /**
+     * Modify the likelihood of specified tokens appearing in the completion.
+     *
+     * Maps tokens (specified by their token ID in the GPT tokenizer) to an associated bias value from -100 to 100.
+     *
+     * https://beta.openai.com/docs/api-reference/completions/create#completions/create-logit_bias
+     */
+    Map<String, Integer> logitBias;
+
     /**
      * A unique identifier representing your end-user, which will help OpenAI to monitor and detect abuse.
      */

client/src/test/java/com/theokanning/openai/CompletionTest.java

@@ -4,6 +4,7 @@ import com.theokanning.openai.completion.CompletionChoice;
 import com.theokanning.openai.completion.CompletionRequest;
 import org.junit.jupiter.api.Test;
 
+import java.util.HashMap;
 import java.util.List;
 
 import static org.junit.jupiter.api.Assertions.assertFalse;
@@ -21,6 +22,7 @@ public class CompletionTest {
                 .prompt("Somebody once told me the world is gonna roll me")
                 .echo(true)
                 .user("testing")
+                .logitBias(new HashMap<>())
                 .build();
 
         List<CompletionChoice> choices = service.createCompletion(completionRequest).getChoices();