CCM-11602: GET Letters endpoint

Author: simonlabarere

internal/datastore/src/letter-repository.ts

@@ -131,15 +131,25 @@ export class LetterRepository {
     return LetterSchema.parse(result.Attributes);
   }
 
-  async getLettersBySupplier(supplierId: string, status: string, size: number, cursor?: string): Promise<Letter[]> {
+  async getLettersBySupplier(supplierId: string, status: string, size: number, cursor?: string): Promise<{
+    nextCursor: string;
+    letters: Letter[]}> {
+    const supplierStatus = `${supplierId}#${status}`;
     const result = await this.ddbClient.send(new QueryCommand({
       TableName: this.config.lettersTableName,
       IndexName: 'supplierStatus-index',
       KeyConditionExpression: 'supplierStatus = :supplierStatus',
       Limit: size,
       ExpressionAttributeValues: {
-        ':supplierStatus': `${supplierId}#${status}`
-      }
+        ':supplierStatus': supplierStatus
+      },
+      ...(cursor != undefined ? {
+        LastEvaluatedKey: {
+          id: cursor,
+          supplierStatus,
+          supplierId,
+        }
+      } : {})
     }));
     this.log.info({
       description: 'items',
@@ -149,6 +159,9 @@ export class LetterRepository {
       cursor,
       result,
     })
-    return z.array(LetterSchema).parse(result.Items);
+    return {
+      nextCursor: result.LastEvaluatedKey.id,
+      letters: z.array(LetterSchema).parse(result.Items)
+    };
   }
 }

lambdas/api-handler/src/handlers/get-letters.ts

@@ -35,9 +35,9 @@ export const getLetters: APIGatewayProxyHandler = async (event) => {
 
     const cursor = event.queryStringParameters?.cursor;
 
-    const letters = await getLettersForSupplier(supplierId, status, Number(size), letterRepo, cursor);
+    const {nextCursor, letters} = await getLettersForSupplier(supplierId, status, Number(size), letterRepo, cursor);
 
-    const response = createGetLettersResponse(event.path, letters, supplierId);
+    const response = createGetLettersResponse(event.path, letters, supplierId, status, size, cursor, nextCursor);
 
     return {
       statusCode: 200,
@@ -54,7 +54,7 @@ export const getLetters: APIGatewayProxyHandler = async (event) => {
 interface GetLettersLinks {
   self: string;
   first: string;
-  last: string;
+  last?: string;
   next?: string;
   prev?: string;
 }
@@ -77,14 +77,18 @@ function createGetLettersResponse(
   baseUrl: string,
   letters: Letter[],
   supplierId: string,
+  status: string,
+  size: string,
+  cursor?: string,
+  nextCursor?: string
 ): GetLettersResponse {
+  const cursorParam = cursor != undefined ? `&cursor=${cursor}` : '';
+  const nextCursorParam = nextCursor != undefined ? `&cursor=${nextCursor}` : '';
   return {
     links: {
-      self: `${baseUrl}?page=1`,
-      first: `${baseUrl}?page=1`,
-      last: `${baseUrl}?page=1`,
-      next: `${baseUrl}?page=1`,
-      prev: `${baseUrl}?page=1`
+      self: `${baseUrl}?status=${status}&size=${size}${cursorParam}`,
+      first: `${baseUrl}?status=${status}&size=${size}`,
+      next: `${baseUrl}?status=${status}&size=${size}${nextCursorParam}`
     },
     data: {
       type: 'Letters',

lambdas/api-handler/src/services/letter-operations.ts

@@ -1,10 +1,12 @@
-import { LetterRepository } from '../../../../internal/datastore/src'
+import { Letter, LetterRepository } from '../../../../internal/datastore/src'
 import { NotFoundError, ValidationError } from '../errors';
 import { LetterApiResource, LetterApiDocument } from '../contracts/letter-api';
 import { toApiLetter } from '../mappers/letter-mapper';
 
 
-export const getLettersForSupplier = async (supplierId: string, status: string, size: number, letterRepo: LetterRepository, cursor?: string): Promise<string[]> => {
+export const getLettersForSupplier = async (supplierId: string, status: string, size: number, letterRepo: LetterRepository, cursor?: string): Promise<{
+    nextCursor: string;
+    letters: Letter[]}> => {
 
   return await letterRepo.getLettersBySupplier(supplierId, status, size, cursor);
 }