> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/getting-started/streaming-snapshot-types.md).

# Streaming Snapshot Types

Openfeed supports `REAL_TIME_SNAPSHOT` and `DELAYED_SNAPSHOT`. Both operate the same way. The service determines whether the data is real-time or delayed.

Set a snapshot service type and the interval for data delivery. See the `SubscriptionRequest.Request` message for additional details.

Snapshot service is currently available only for symbol subscriptions.

The following message flow shows a 15-second real-time snapshot subscription.

### Real-time snapshot subscription example

```protobuf
Sending: subscriptionRequest {
  token: "b35720bb-0788-4d4f-b170-4701c8204301"
  service: REAL_TIME_SNAPSHOT
  requests {
    symbol: "^EURUSD"
    subscriptionType: TRADES
    snapshotIntervalSeconds: 15
  }
}

subscriptionResponse {
  status {
    result: SUCCESS
    service: REAL_TIME_SNAPSHOT
  }
  symbol: "^EURUSD"
  marketId: 8663698093865741069
  channelId: 13
  subscriptionType: TRADES
}

instrumentDefinition {
  marketId: 8663698093865741069
  instrumentType: FOREX
  vendorId: "FOREX"
  symbol: "^EURUSD"
  exchangeCode: "FOREX"
  recordCreateTime: 1631133721587
  recordUpdateTime: 1631133721587
  timeZoneName: "America/Chicago"
  channel: 13
  priceFormat {
    denominator: 100000
    subDenominator: 1
  }
  priceDenominator: 1000000
  quantityDenominator: 1
  symbols {
    vendor: "Barchart"
    symbol: "^EURUSD"
  }
  subscriptionSymbol: "^EURUSD"
}

// Initial MarketSnapshot

marketSnapshot {
  marketId: 8663698093865741069
  transactionTime: 1634155017627648000
  marketSequence: 8434383
  tradeDate: 20211013
  totalChunks: 1
  currentChunk: 1
  symbol: "^EURUSD"
  service: REAL_TIME_SNAPSHOT
  instrumentStatus {
    tradingStatus: OPEN
    tradeDate: 20211013
  }
  bbo {
    bidPrice: 1159400
    bidOriginator: "SURF:LDN"
    offerPrice: 1159700
    offerOriginator: "SURF:LDN"
  }
  open {
    price: 1152969
  }
  high {
    price: 1159713
  }
  low {
    price: 1152657
  }
  last {
    tradeDate: 20211013
    price: 1159443
    quantity: 1
  }
  volume {
    volume: 165788
  }
  numberOfTrades {
    numberTrades: 165788
  }
  monetaryValue {
    value: 19065620
  }
  previousSession {
    tradeDate: 20211012
    open {
      price: 1155223
    }
    high {
      price: 1157013
    }
    low {
      price: 1152427
    }
    last {
      tradeDate: 20211012
      price: 1152974
      quantity: 1
    }
    volume {
      volume: 144627
    }
    settlement {
      tradeDate: 20211012
      price: 1152974
    }
    numberOfTrades {
      numberTrades: 144627
    }
    monetaryValue {
      value: 16632105
    }
    prevSettlement {
      tradeDate: 20211011
      price: 1155255
    }
  }
}

// MarketSnapshot 15 Seconds Later

marketSnapshot {
  marketId: 8663698093865741069
  transactionTime: 1634155034763987000
  marketSequence: 8434429
  tradeDate: 20211013
  totalChunks: 1
  currentChunk: 1
  symbol: "^EURUSD"
  service: REAL_TIME_SNAPSHOT
  instrumentStatus {
    tradingStatus: OPEN
    tradeDate: 20211013
  }
  bbo {
    bidPrice: 1159370
    bidOriginator: "BNPF:PAR"
    offerPrice: 1159400
    offerOriginator: "BNPF:PAR"
  }
  open {
    price: 1152969
  }
  high {
    price: 1159713
  }
  low {
    price: 1152657
  }
  last {
    tradeDate: 20211013
    price: 1159393
    quantity: 1
  }
  volume {
    volume: 165809
  }
  numberOfTrades {
    numberTrades: 165809
  }
  monetaryValue {
    value: 19068035
  }
  previousSession {
    tradeDate: 20211012
    open {
      price: 1155223
    }
    high {
      price: 1157013
    }
    low {
      price: 1152427
    }
    last {
      tradeDate: 20211012
      price: 1152974
      quantity: 1
    }
    volume {
      volume: 144627
    }
    settlement {
      tradeDate: 20211012
      price: 1152974
    }
    numberOfTrades {
      numberTrades: 144627
    }
    monetaryValue {
      value: 16632105
    }
    prevSettlement {
      tradeDate: 20211011
      price: 1155255
    }
  }
}

...
```


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