QuantConnect.Lean.Engine.DataFeeds.BaseDownloaderDataProvider Class Referenceabstract
Base downloader implementation with some helper methods More...
Inheritance diagram for QuantConnect.Lean.Engine.DataFeeds.BaseDownloaderDataProvider:
Protected Member Functions | |
| Stream | DownloadOnce (string key, Action< string > download) |
| Helper method which guarantees each requested key is downloaded only once concurrently if required based on NeedToDownload More... | |
| virtual Stream | GetStream (string key) |
| Get's the stream for a given file path More... | |
| abstract bool | NeedToDownload (string filePath) |
| Main filter to determine if this file needs to be downloaded More... | |
 Protected Member Functions inherited from QuantConnect.Lean.Engine.DataFeeds.DefaultDataProvider | |
| virtual void | OnNewDataRequest (DataProviderNewDataRequestEventArgs e) |
| Event invocator for the NewDataRequest event More... | |
Additional Inherited Members | |
| Public Member Functions inherited from QuantConnect.Lean.Engine.DataFeeds.DefaultDataProvider | |
| virtual Stream | Fetch (string key) |
| Retrieves data from disc to be used in an algorithm More... | |
| void | Dispose () |
| The stream created by this type is passed up the stack to the IStreamReader The stream is closed when the StreamReader that wraps this stream is disposed More... | |
| Events inherited from QuantConnect.Lean.Engine.DataFeeds.DefaultDataProvider | |
| EventHandler< DataProviderNewDataRequestEventArgs > | NewDataRequest |
| Event raised each time data fetch is finished (successfully or not) More... | |
| Events inherited from QuantConnect.Interfaces.IDataProvider | |
| EventHandler< DataProviderNewDataRequestEventArgs > | NewDataRequest |
| Event raised each time data fetch is finished (successfully or not) More... | |
Detailed Description
Base downloader implementation with some helper methods
Definition at line 26 of file BaseDownloaderDataProvider.cs.
Member Function Documentation
◆ DownloadOnce()
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protected |
Helper method which guarantees each requested key is downloaded only once concurrently if required based on NeedToDownload
- Parameters
-
key A string representing where the data is stored download The download operation we want to perform once concurrently per key
- Returns
- A Stream of the data requested
Definition at line 39 of file BaseDownloaderDataProvider.cs.
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◆ GetStream()
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protectedvirtual |
Get's the stream for a given file path
Reimplemented in QuantConnect.Lean.Engine.DataFeeds.DownloaderDataProvider.
Definition at line 57 of file BaseDownloaderDataProvider.cs.
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◆ NeedToDownload()
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protectedpure virtual |
Main filter to determine if this file needs to be downloaded
- Parameters
-
filePath File we are looking at
- Returns
- True if should download
Implemented in QuantConnect.Lean.Engine.DataFeeds.DownloaderDataProvider, and QuantConnect.Lean.Engine.DataFeeds.ApiDataProvider.
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The documentation for this class was generated from the following file:
- Engine/DataFeeds/BaseDownloaderDataProvider.cs
