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Is it possible to write to database or file using a local instance of Lean?
regards,
Felipe
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Jasper van Merle
Hi Felipe,
Yes, you can do both of that.
If you want to read from/write to files you should use the data directory (or a path inside that directory), because the data directory is mounted into every Docker container ran by the CLI. You can get the path to this directory in your algorithm using the `Globals.DataFolder` variable, and use your programming language's normal filesystem APIs to interact with the contents of it.
If you want to use a MySQL database, it's probably easiest to use the CLI's Custom libraries feature with your preferred library for connecting to your database. You can use custom libraries like usual, but keep in mind that when you want to connect to a database running on a localhost port you must replace the localhost part with host.docker.internal. In other words, instead of connecting to “localhost:3306" you would connect to “host.docker.internal:3306”.
Felipe Ludena
The material on this website is provided for informational purposes only and does not constitute an offer to sell, a solicitation to buy, or a recommendation or endorsement for any security or strategy, nor does it constitute an offer to provide investment advisory services by QuantConnect. In addition, the material offers no opinion with respect to the suitability of any security or specific investment. QuantConnect makes no guarantees as to the accuracy or completeness of the views expressed in the website. The views are subject to change, and may have become unreliable for various reasons, including changes in market conditions or economic circumstances. All investments involve risk, including loss of principal. You should consult with an investment professional before making any investment decisions.
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