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OMG API
OMG API

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OMG Game Aggregation Platform — Complete API Integration Guide (Single Wallet & Transfer Wallet)

What is OMG?

OMG (docs.omgapi.cc) is a professional game aggregation platform that provides third-party merchants with a unified API to access a wide variety of game content:

  • Slots — classic and video slot machines
  • Fishing Games — skill-based arcade fishing titles
  • Mass Table Games — multi-player table games
  • Mini Games — lightweight casual game modules

Merchants integrate once and gain access to the full OMG game library, with centralized wallet management, bet record reporting, and player RTP control.

Two Wallet Modes

OMG supports two mutually exclusive wallet architectures:

Single Wallet

  • Player balance is maintained by the merchant.
  • OMG calls back the merchant for balance queries and changes.
  • Merchant must implement: verify_session, get_balance, change_balance.

Transfer Wallet

  • Player balance is maintained by OMG.
  • Merchant actively calls OMG to transfer funds in/out.
  • No callbacks needed — merchant only calls OMG APIs.
Dimension Single Wallet Transfer Wallet
Balance owner Merchant OMG platform
Enter game API /api/usr/ingame /api/game/v1/entergame
Token source Merchant's own auth OMG /api/player/v1/authorize
Balance change OMG callbacks merchant Merchant calls OMG /api/cash/v1/transfer

MD5 Signature Authentication (Critical!)

Every API request must be signed:

sign = md5( URL_query_string + raw_body_JSON + secret_key )
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Key rules:

  • MD5 result must be lowercase hex
  • Body must use the original raw JSON bytes — never re-serialize after parsing
  • sign goes in the HTTP header, not the body
  • URL query string (e.g., trace_id=xxx) must be included in the signature

Go Implementation Example 

// Sending a request
bodyBytes := []byte(`{"player_logon_token":"...","account_id":"1002402","timestamp":1711971655}`)
urlQuery := "trace_id=" + traceID
toSign := urlQuery + string(bodyBytes) + key
sign := fmt.Sprintf("%x", md5.Sum([]byte(toSign))) // lowercase hex

req, _ := http.NewRequest("POST", url+"?"+urlQuery, bytes.NewReader(bodyBytes))
req.Header.Set("Content-Type", "application/json; charset=utf-8")
req.Header.Set("sign", sign)
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Response Code Convention (Common Bug Source!)

Interface Type Success Code
Merchant to OMG (game APIs) code = 0
OMG to Merchant callbacks (Single Wallet) code = 1
Backend / report APIs code = 1

If your callback returns code=0, OMG will treat it as a failure and keep retrying!

Single Wallet Flow 

1. Merchant -> OMG: /api/usr/ingame          -> get game URL
2. Player visits game URL
3. OMG -> Merchant: /api/luck/user/verify_session    (verify token)
4. OMG -> Merchant: /api/luck/balance/get_balance    (query balance)
5. OMG -> Merchant: /api/luck/balance/change_balance (bet/payout/cancel)
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change_balance Transaction Types

type Meaning money sign
1 Bet negative
2 Cancel bet (rollback) positive
3 Payout positive
4 Verify round end 0
5 LuckWin bonus positive

Common Pitfalls & Fixes

Symptom Root Cause Fix
Always 10002 sign invalid Body re-serialized before signing Use raw request bytes
Sign correct but still fails URL query not in sign string Include query in concatenation
OMG keeps retrying callback Returned code=0 instead of code=1 Return code=1 on success
Duplicate deductions No idempotency on order_id Add unique constraint
Amount precision loss Parsed as float Use string/Decimal, 4 decimal places

Resources

Contact

For business inquiries and integration support:

This guide is based on the complete integration skill available at github.com/omgapi/omg-api-integration.

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