Lib.rs

OptionChain-Simulator API and Architecture

System Architecture

flowchart TD
Client[Client Applications] --> API[API Layer]
API --> SM[Session Management]
SM --> App[Application Layer]
App --> Domain[Domain Layer]
App --> Infra[Infrastructure Layer]
Domain --> SimEngine[Simulation Engine]
Infra --> ClickHouse[(ClickHouse DB)]
Infra --> Redis[(Redis)]
Infra --> MongoDB[(MongoDB)]

Session State Transitions

stateDiagram-v2
[*] --> Initialized: POST /api/v1/chain
Initialized --> InProgress: GET
InProgress --> InProgress: GET
InProgress --> Modified: PATCH
Modified --> InProgress: GET
InProgress --> Reinitialized: PUT
Modified --> Reinitialized: PUT
Reinitialized --> InProgress: GET
Initialized --> [*]: DELETE
InProgress --> [*]: DELETE
Modified --> [*]: DELETE
Reinitialized --> [*]: DELETE

API Request Flow

sequenceDiagram
participant Client
participant API as REST API
participant SM as Session Manager
participant SS as Simulator Service

Client->>API: POST /api/v1/chain
API->>SM: Create new session
SM->>SS: Initialize simulation
SS-->>SM: Initial state
SM-->>API: Session created (id: abc123)
API-->>Client: 201 Created (session details)

Client->>API: GET /api/v1/chain
API->>SM: Get next step
SM->>SS: Advance simulation
SS-->>SM: Step data
SM-->>API: Chain data
API-->>Client: 200 OK (Chain data)

REST API Endpoints

The OptionChain-Simulator exposes the following REST API endpoints:

Request/Response Models

1. Create Session (POST /api/v1/chain)

Request Body:

{
  "symbol": "AAPL",
  "steps": 10,
  "initial_price": 185.5,
  "days_to_expiration": 45.0,
  "volatility": 0.25,
  "risk_free_rate": 0.04,
  "dividend_yield": 0.005,
  "method": {
    "GeometricBrownian": {
      "dt": 0.004,
      "drift": 0.05,
      "volatility": 0.25
    }
  },
  "time_frame": "Day",
  "chain_size": 15,
  "strike_interval": 5.0,
  "smile_curve": 0.0005,
  "spread": 0.02
}

Response (201 Created):

{
    "id": "6af613b6-569c-5c22-9c37-2ed93f31d3af",
    "created_at": "2025-04-21T15:37:30.518022+00:00",
    "updated_at": "2025-04-21T15:37:30.518022+00:00",
    "parameters": {
        "symbol": "AAPL",
        "initial_price": 185.5,
        "volatility": 0.25,
        "risk_free_rate": 0.04,
        "method": "GeometricBrownian { dt: 0.004, drift: 0.05, volatility: 0.25 }",
        "time_frame": "day",
        "dividend_yield": 0.005,
        "smile_curve": 0.0005,
        "spread": 0.02
    },
    "current_step": 0,
    "total_steps": 10,
    "state": "Initialized"
}

2. Get Next Step (GET /api/v1/chain?sessionid=6af613b6-569c-5c22-9c37-2ed93f31d3af)

Response (200 OK):

{
    "underlying": "AAPL",
    "timestamp": "2025-04-21T15:33:03.597061+00:00",
    "price": 185.299430466522,
    "contracts": [
        {
            "strike": 160.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 26.08,
                "ask": 26.1,
                "mid": 26.09,
                "delta": 0.9993778215543331
            },
            "put": {
                "bid": null,
                "ask": null,
                "mid": null,
                "delta": -4.2479708093406946e-6
            },
            "implied_volatility": 0.09731095458186256,
            "gamma": 3.121236702609213e-6
        },
        {
            "strike": 165.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 21.14,
                "ask": 21.16,
                "mid": 21.15,
                "delta": 0.9888998386575956
            },
            "put": {
                "bid": 0.03,
                "ask": 0.05,
                "mid": 0.04,
                "delta": -0.010482230867546823
            },
            "implied_volatility": 0.15077922021760087,
            "gamma": 0.0028266289100911603
        },
        {
            "strike": 170.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 16.62,
                "ask": 16.64,
                "mid": 16.63,
                "delta": 0.9153696474659715
            },
            "put": {
                "bid": 0.49,
                "ask": 0.51,
                "mid": 0.5,
                "delta": -0.08401242205917087
            },
            "implied_volatility": 0.1927733286389461,
            "gamma": 0.012279670056243013
        },
        {
            "strike": 175.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 12.87,
                "ask": 12.89,
                "mid": 12.88,
                "delta": 0.7964192920937592
            },
            "put": {
                "bid": 1.71,
                "ask": 1.73,
                "mid": 1.72,
                "delta": -0.2029627774313833
            },
            "implied_volatility": 0.22329327984589836,
            "gamma": 0.019409579420062936
        },
        {
            "strike": 180.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 9.76,
                "ask": 9.78,
                "mid": 9.77,
                "delta": 0.6700429413591044
            },
            "put": {
                "bid": 3.57,
                "ask": 3.59,
                "mid": 3.58,
                "delta": -0.3293391281660381
            },
            "implied_volatility": 0.24233907383845762,
            "gamma": 0.022910122989513254
        },
        {
            "strike": 185.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 7.09,
                "ask": 7.11,
                "mid": 7.1,
                "delta": 0.5468721177394451
            },
            "put": {
                "bid": 5.87,
                "ask": 5.89,
                "mid": 5.88,
                "delta": -0.45250995178569736
            },
            "implied_volatility": 0.24991071061662393,
            "gamma": 0.024315069945191076
        },
        {
            "strike": 190.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 4.68,
                "ask": 4.7,
                "mid": 4.69,
                "delta": 0.4237521134194814
            },
            "put": {
                "bid": 8.45,
                "ask": 8.47,
                "mid": 8.46,
                "delta": -0.5756299561056611
            },
            "implied_volatility": 0.24385078722742481,
            "gamma": 0.024638652336979393
        },
        {
            "strike": 195.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 2.62,
                "ask": 2.64,
                "mid": 2.63,
                "delta": 0.29452137751494756
            },
            "put": {
                "bid": 11.36,
                "ask": 11.38,
                "mid": 11.37,
                "delta": -0.7048606920101947
            },
            "implied_volatility": 0.22617927813392658,
            "gamma": 0.023389127623181388
        },
        {
            "strike": 200.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 1.03,
                "ask": 1.05,
                "mid": 1.04,
                "delta": 0.15952905609846607
            },
            "put": {
                "bid": 14.75,
                "ask": 14.77,
                "mid": 14.76,
                "delta": -0.8398530134266764
            },
            "implied_volatility": 0.19703361182603538,
            "gamma": 0.01891326128023662
        },
        {
            "strike": 205.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": 0.16,
                "ask": 0.18,
                "mid": 0.17,
                "delta": 0.04271051015963935
            },
            "put": {
                "bid": 18.85,
                "ask": 18.87,
                "mid": 18.86,
                "delta": -0.9566715593655031
            },
            "implied_volatility": 0.15641378830375124,
            "gamma": 0.008916660747165772
        },
        {
            "strike": 210.0,
            "expiration": "2025-06-05",
            "call": {
                "bid": null,
                "ask": null,
                "mid": null,
                "delta": 0.0005597778266970925
            },
            "put": {
                "bid": 23.66,
                "ask": 23.68,
                "mid": 23.67,
                "delta": -0.9988222916984453
            },
            "implied_volatility": 0.10431980756707404,
            "gamma": 0.0002902662707065403
        }
    ],
    "session_info": {
        "id": "6af613b6-569c-5c22-9c37-2ed93f31d3af",
        "current_step": 1,
        "total_steps": 10
    }
}

3. Update Session Parameters (PATCH /api/v1/chain?sessionid=6af613b6-569c-5c22-9c37-2ed93f31d3af)

Request Body:

{
  "symbol": "AAPL",
   "initial_price": 385.5,
  "steps": 8,
  "volatility": 0.2,
  "risk_free_rate": 0.03,
  "dividend_yield": 0.005,
  "days_to_expiration": 30.0,
  "time_frame": "Day"
}

Response (200 OK):

{
    "id": "6af613b6-569c-5c22-9c37-2ed93f31d3af",
    "created_at": "2025-04-21T15:32:59.551486+00:00",
    "updated_at": "2025-04-21T15:33:19.515911+00:00",
    "parameters": {
        "symbol": "AAPL",
        "initial_price": 385.5,
        "volatility": 0.2,
        "risk_free_rate": 0.03,
        "method": "GeometricBrownian { dt: 0.004, drift: 0.05, volatility: 0.25 }",
        "time_frame": "day",
        "dividend_yield": 0.005,
        "smile_curve": 0.0005,
        "spread": 0.02
    },
    "current_step": 0,
    "total_steps": 30,
    "state": "Reinitialized"
}

4. Replace Session (PUT /api/v1/chain)

Request Body:

{
  "symbol": "AAPL",
  "steps": 30,
  "initial_price": 385.5,
  "days_to_expiration": 45.0,
  "volatility": 0.25,
  "risk_free_rate": 0.04,
  "dividend_yield": 0.005,
  "method": {
    "GeometricBrownian": {
      "dt": 0.004,
      "drift": 0.05,
      "volatility": 0.25
    }
  },
  "time_frame": "Day",
  "chain_size": 15,
  "strike_interval": 5.0,
  "smile_curve": 0.0005,
  "spread": 0.02
}

Response (200 OK):

{
    "id": "6af613b6-569c-5c22-9c37-2ed93f31d3af",
    "created_at": "2025-04-21T15:37:30.518022+00:00",
    "updated_at": "2025-04-21T15:37:33.951540+00:00",
    "parameters": {
        "symbol": "AAPL",
        "initial_price": 385.5,
        "volatility": 0.25,
        "risk_free_rate": 0.04,
        "method": "GeometricBrownian { dt: 0.004, drift: 0.05, volatility: 0.25 }",
        "time_frame": "day",
        "dividend_yield": 0.005,
        "smile_curve": 0.0005,
        "spread": 0.02
    },
    "current_step": 0,
    "total_steps": 30,
    "state": "Reinitialized"
}

5. Delete Session (DELETE /api/v1/chain?sessionid=6af613b6-569c-5c22-9c37-2ed93f31d3af)

Response (200 OK):

{
    "message": "Session deleted successfully: 6af613b6-569c-5c22-9c37-2ed93f31d3af",
    "session_id": "6af613b6-569c-5c22-9c37-2ed93f31d3af"
}

Domain Models

classDiagram
class SessionManager {
+createSession(params) Session
+getNextStep(id) (Session, OptionChain)
+updateSession(id, params) Session
+reinitializeSession(id, params) Session
+deleteSession(id) bool
}

class Session {
+id UUID
+createdAt DateTime
+updatedAt DateTime
+parameters SimulationParameters
+currentStep usize
+totalSteps usize
+state SessionState
+advanceStep() Result
+modifyParameters(params)
+reinitialize(params, steps)
}

class SessionState {
<<enumeration>>
Initialized
InProgress
Modified
Reinitialized
Completed
Error
}

class SimulationParameters {
+symbol String
+initialPrice Positive
+volatility Positive
+riskFreeRate Decimal
+strikes Vec~Positive~
+expirations Vec~String~
+method SimulationMethod
+timeFrame TimeFrame
}

class Simulator {
+simulateNextStep(session) OptionChain
-createRandomWalk(session) RandomWalk
}

class OptionChain {
+underlying String
+timestamp DateTime
+price Positive
+contracts Vec~OptionContract~
}

class OptionContract {
+strike Positive
+expiration String
+call OptionData
+put OptionData
+impliedVolatility Positive
+gamma Positive
}

Session --> SimulationParameters
Session --> SessionState
SessionManager --> Session: manages
SessionManager --> Simulator: uses
Simulator --> OptionChain: produces
OptionChain --> OptionContract: contains

Infrastructure Components

classDiagram
class SessionStore {
<<interface>>
+get(id) Session
+save(session) void
+delete(id) bool
+cleanup() int
}

class InMemorySessionStore {
-sessions Map~UUID, Session~
+get(id) Session
+save(session) void
+delete(id) bool
+cleanup() int
}

class RedisSessionStore {
-client RedisClient
+get(id) Session
+save(session) void
+delete(id) bool
+cleanup() int
}

class HistoricalDataRepository {
<<interface>>
+getHistoricalPrices(symbol, timeframe, startDate, endDate) Vec~Positive~
+listAvailableSymbols() Vec~String~
+getDateRangeForSymbol(symbol) (DateTime, DateTime)
}

class ClickHouseHistoricalRepository {
-client ClickHouseClient
+getHistoricalPrices(symbol, timeframe, startDate, endDate) Vec~Positive~
+listAvailableSymbols() Vec~String~
+getDateRangeForSymbol(symbol) (DateTime, DateTime)
}

SessionStore <|.. InMemorySessionStore: implements
SessionStore <|.. RedisSessionStore: implements
HistoricalDataRepository <|.. ClickHouseHistoricalRepository: implements

🚀 Deploy the project

To deploy the services defined in Docker/docker-compose.yml, run the following command:

make deploy

This will:

• Build the Docker images (--build)
• Force container recreation (--force-recreate)
• Run everything in detached mode (-d)
• Use optionchain-simulator as the project name to namespace containers and resources

Make sure Docker and Docker Compose are installed and running on your system.

Makefile Commands for Development

The project includes a Makefile with useful commands for development:

Additional commands for CI/CD and deployment:

Contribution and Contact

We welcome contributions to this project! If you would like to contribute, please follow these steps:

1. Fork the repository.
2. Create a new branch for your feature or bug fix.
3. Make your changes and ensure that the project still builds and all tests pass.
4. Commit your changes and push your branch to your forked repository.
5. Submit a pull request to the main repository.

If you have any questions, issues, or would like to provide feedback, please feel free to contact the project maintainer:

Joaquín Béjar García

• Email: jb@taunais.com
• GitHub: joaquinbejar

We appreciate your interest and look forward to your contributions!

✍️ License

Licensed under MIT license