gemini coding challenge

problem

The new order API endpoint is described here. How will you test it?

• Please code up functional test cases in the language of your choice or pseudocode.
• Include both positive and negative cases.
• Be able to quantify the number of distinct tests run.
• Do not invoke any other API endpoints (e.g., order status).
• Clearly articulate your assumptions.

sandbox

• URL: https://api.sandbox.gemini.com
• Key: $key
• Secret: $secret

solution

See solution.md.

how I tested this feature

Using postman, I was able to get a request through to the endpoint with the below steps. However, we wont be able to use the same headers to generate another 200 response. In order to make another successful request, we'd need to regenerate a few pieces of information. I generated my payload and signature, with the following steps:

1. Create a payload.json

   {
     "client_order_id": "20150102-4738721",
     "symbol": "btcusd",
     "amount": "34.12",
     "price": "622.13",
     "side": "buy",
     "type": "exchange limit",
     "options": ["maker-or-cancel"],
     "request": "/v1/order/new",
     "nonce": 1000000000
   }

   • nonce needs to be noted and incremented as requests are made

2. After creating the payload.json, I used a shell script to convert my JSON in to base64:

   openssl base64 -in $1 -out $2

3. Then I used another shell script to create my encrypted signature:

   echo -n $1 | openssl sha384 -hmac $2

4. Finally this gave me my full header:

   POST /v1/order/new HTTP/1.1
   Host: api.sandbox.gemini.com
   Content-Length: 0
   Content-Type: multipart/form-data; boundary=----WebKitFormBoundary7MA4YWxkTrZu0gW
   X-GEMINI-APIKEY: 0Ad2raecQBpUJs8difrv
   X-GEMINI-PAYLOAD: ewogICJjbGllbnRfb3JkZXJfaWQiOiAiMjAxNTAxMDItNDczODcyMSIsCiAgInN5bWJvbCI6ICJidGN1c2QiLAogICJhbW91bnQiOiAiMzQuMTIiLAogICJwcmljZSI6ICI2MjIuMTMiLAogICJzaWRlIjogImJ1eSIsCiAgInR5cGUiOiAiZXhjaGFuZ2UgbGltaXQiLAogICJvcHRpb25zIjogWyJtYWtlci1vci1jYW5jZWwiXSwKICAicmVxdWVzdCI6ICIvdjEvb3JkZXIvbmV3IiwKICAibm9uY2UiOiAxMDAwMDAwMDAwCn0K
   X-GEMINI-SIGNATURE: a8609f88b6d9b4f4cf9ed35afe5106473fd315961ca8d53b1549e5aecfcfe7aba3bac8dd00640570fc772155bdb535d0
   Cache-Control: no-cache
   Postman-Token: 78402821-bc4e-f3f5-b7d8-f2b82f16c180

5. After sending my request, I got a response like:

   {
       "order_id": "103413857",
       "id": "103413857",
       "symbol": "btcusd",
       "exchange": "gemini",
       "avg_execution_price": "0.00",
       "side": "buy",
       "type": "exchange limit",
       "timestamp": "1535005846",
       "timestampms": 1535005846365,
       "is_live": true,
       "is_cancelled": false,
       "is_hidden": false,
       "was_forced": false,
       "executed_amount": "0",
       "remaining_amount": "34.12",
       "client_order_id": "20150102-4738721",
       "options": [
           "maker-or-cancel"
       ],
       "price": "622.13",
       "original_amount": "34.12"
   }

running our automation commands

To use these scripts, you need a secret.json and you need to increment the start.js at the root of the project.

secret.js

module.exports = {
  key: '$secret',
  api: '$apikey'
}

start.js

module.exports = 3000000000

I've created a couple of scripts to help our goal of automating this as a test. You can skip steps 2-5 with npm run new:files

Run npm install, then:

1. Create the folder structure: npm run init
2. Generate a new payload: npm run new:payload
3. Convert a new payload: npm run new:convert
4. Create a signature with key and payload: npm run new:signature
5. Generate a header: npm run new:header
6. Lastly, make a request with npm run new:request

Again, you only have to run npm run new:files and npm run new:request.

testing our commands

npm run test