Translate Api

translation api that uses bing-translate-apid

Designing

the app is divided into 4 modules

• server.js
  this is the main api server that recives calls

• apiFetch.js
  this module act between the server.js and the cachingDB.js is mainly for remote api for translate and for giving data to cashingDB.js

• cachingDB.js
  takes care of the cache db like updating cache,deleting old entries .

in remote

in this senario we expect the result is in remote and not in cache .

• 1 end user makes request to the server
• 2 server.js makes a request to (following arrow 3 )apiFetch.js which then makes a request to caching.js (following arrow 5 )to check the cache server where it gets a cache miss it returns undefined. following arrow 6
• 7 apiFetch.js makes a request to remote api and gets the result (arrow 8 ) apiFetch.js stores the data following the paths then finally returns to server.js it then send response to the end user.

in cache

• 1 end user makes request to the server
• 2 server.js makes a request to (following arrow 3 )apiFetch.js which then makes
• apifetch makes a request to cachedb.js via 3 then gets response following 5 and 4 returns responce following path 6 9 10

Installation

# clone repo 
git clone https://github.com/Ayan-web/translateApi.git api

cd api
npm install

add a .env in the root of the project with the following

cat .env
PORT=8080 # server port
host=localhost #server hosting address
user=dataconnect # database username
password=connectplease # database password
database=caching # database/schema name
table=cache # table name
cacheSize=2 # cache size

## Running

```sh
npm start
> translateRESTApi@1.0.0 start
> node src/index.js

listening on http://localhost:8080

Testing

we have used jest and supertest to end to end test

npm test
> translateRESTApi@1.0.0 test
> jest

 PASS  tests/api.test.js (14.938 s)
  endpoint testing 
    ✓ get response 200 (4840 ms)
    ✓ maching response with cache db (55 ms)
  cache db test
    ✓ watching that catch size not increasing catch size (9046 ms)

Test Suites: 1 passed, 1 total
Tests:       3 passed, 3 total
Snapshots:   0 total
Time:        15.033 s, estimated 20 s
Ran all test suites.

Consuming

the uri syntax in
http://localhost:8080/text/source-target

curl -s http://localhost:8080/hello/en-bn  

{"text":"hello","from":"en","to":"bn","translation":"নমস্কার"}                                               

for target and source follow lang.js.

Caching

we have used FIFO caching policy for this project as it is the easiest to implement. we are using MySql 8 as cache database.

mysql> desc cache;
+-------------+-------------+------+-----+-------------------+-------------------+
| Field       | Type        | Null | Key | Default           | Extra             |
+-------------+-------------+------+-----+-------------------+-------------------+
| keytext     | varchar(20) | NO   |     | NULL              |                   |
| translate   | varchar(40) | NO   |     | NULL              |                   |
| target      | varchar(4)  | NO   |     | NULL              |                   |
| createdtime | timestamp   | NO   |     | CURRENT_TIMESTAMP | DEFAULT_GENERATED |
| id          | tinyint     | NO   | PRI | NULL              | auto_increment    |
+-------------+-------------+------+-----+-------------------+-------------------+
5 rows in set (0.00 sec)