feat: update translation endpoint to be compatible for different endp…

…oints

src/controllers/translation.ts

@@ -1,6 +1,6 @@
 import axios from 'axios';
 import { MiddleWare } from '../types';
-import { IGBO_TO_ENGLISH_API, MAIN_KEY } from '../config';
+import { ENGLIGH_TO_IGBO_API, IGBO_TO_ENGLISH_API, MAIN_KEY } from '../config';
 import { z } from 'zod';
 import { fromError } from 'zod-validation-error';
 import LanguageEnum from '../shared/constants/LanguageEnum';
@@ -19,9 +19,18 @@ export interface Translation {
   translation: string;
 }
 
-// Due to limit on inputs used to train the model, the maximum
-// Igbo translation input is 120 characters
-const IGBO_ENGLISH_TRANSLATION_INPUT_MAX_LENGTH = 120;
+// TODO: move this information to remote config
+const SUPPORTED_TRANSLATIONS = {
+  [`${LanguageEnum.IGBO}to${LanguageEnum.ENGLISH}`]: {
+    maxInputLength: 120,
+    translationAPI: IGBO_TO_ENGLISH_API,
+  },
+  [`${LanguageEnum.ENGLISH}to${LanguageEnum.IGBO}`]: {
+    maxInputLength: 150,
+    translationAPI: ENGLIGH_TO_IGBO_API,
+  },
+} as const;
+type SupportedTranslationCodes = keyof typeof SUPPORTED_TRANSLATIONS;
 
 /**
  * Talks to Igbo-to-English translation model to translate the provided text.
@@ -32,43 +41,48 @@ const IGBO_ENGLISH_TRANSLATION_INPUT_MAX_LENGTH = 120;
  */
 export const getTranslation: MiddleWare = async (req, res, next) => {
   try {
-    console.log('entered translation endpoint');
-    console.log('request body', req.body);
     const requestBodyValidation = TranslationRequestBody.safeParse(req.body);
     if (!requestBodyValidation.success) {
       throw fromError(requestBodyValidation.error);
     }
 
     const requestBody = requestBodyValidation.data;
-    console.log(`validation succeeded, body: ${requestBody}`);
 
     if (requestBody.sourceLanguageCode === requestBody.destinationLanguageCode) {
       throw new Error('Source and destination languages must be different');
     }
+
     if (
-      requestBody.sourceLanguageCode !== LanguageEnum.IGBO ||
-      requestBody.destinationLanguageCode !== LanguageEnum.ENGLISH
+      !(
+        `${requestBody.sourceLanguageCode}to${requestBody.destinationLanguageCode}` in
+        SUPPORTED_TRANSLATIONS
+      )
     ) {
       throw new Error(
         `${requestBody.sourceLanguageCode} to ${requestBody.destinationLanguageCode} translation is not yet supported`
       );
     }
-    const igboText = requestBody.text;
-    if (!igboText) {
+    const textToTranslate = requestBody.text;
+    if (!textToTranslate) {
       throw new Error('Cannot translate empty string');
     }
-
-    if (igboText.length > IGBO_ENGLISH_TRANSLATION_INPUT_MAX_LENGTH) {
-      throw new Error('Cannot translate text greater than 120 characters');
+    const translationKey =
+      `${requestBody.sourceLanguageCode}to${requestBody.destinationLanguageCode}` as SupportedTranslationCodes;
+    // TODO: update this use map based on language
+    if (textToTranslate.length > SUPPORTED_TRANSLATIONS[translationKey].maxInputLength) {
+      throw new Error(
+        `Cannot translate text greater than ${SUPPORTED_TRANSLATIONS[translationKey].maxInputLength} characters`
+      );
     }
 
-    const payload: IgboEnglishTranslationMetadata = { igbo: igboText };
+    // TODO: joint model will standardize request
+    const payload =
+      translationKey == 'ibotoeng' ? { igbo: textToTranslate } : { english: textToTranslate };
 
     // Talks to translation endpoint
-    console.log('making translation request');
     const { data: response } = await axios.request<Translation>({
       method: 'POST',
-      url: IGBO_TO_ENGLISH_API,
+      url: SUPPORTED_TRANSLATIONS[translationKey].translationAPI,
       headers: {
         'Content-Type': 'application/json',
         'X-API-Key': MAIN_KEY,