freqtrade_origin/docs/freqai-developers.md
2022-10-03 11:01:58 +02:00

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Development

Project architecture

The architecture and functions of FreqAI are generalized to encourages development of unique features, functions, models, etc.

The class structure and a detailed algorithmic overview is depicted in the following diagram:

image

As shown, there are three distinct objects comprising FreqAI:

  • IFreqaiModel - A singular persistent object containing all the necessary logic to collect, store, and process data, engineer features, run training, and inference models.
  • FreqaiDataKitchen - A non-persistent object which is created uniquely for each unique asset/model. Beyond metadata, it also contains a variety of data processing tools.
  • FreqaiDataDrawer - A singular persistent object containing all the historical predictions, models, and save/load methods.

There are a variety of built-in prediction models which inherit directly from IFreqaiModel. Each of these models have full access to all methods in IFreqaiModel and can therefore override any of those functions at will. However, advanced users will likely stick to overriding fit(), train(), predict(), and data_cleaning_train/predict().

Data handling

FreqAI aims to organize model files, prediction data, and meta data in a way that simplifies post-processing and enhances crash resilience by automatic data reloading. The data is saved in a file structure,user_data_dir/models/, which contains all the data associated with the trainings and backtests. The FreqaiDataKitchen() relies heavily on the file structure for proper training and inferencing and should therefore not be manually modified.

File structure

The file structure is automatically generated based on the model identifier set in the config. The following structure shows where the data is stored for post processing:

Structure Description
config_*.json A copy of the model specific configuration file.
historic_predictions.pkl A file containing all historic predictions generated during the lifetime of the identifier model during live deployment. historic_predictions.pkl is used to reload the model after a crash or a config change. A backup file is always held in case of corruption on the main file. FreqAI automatically detects corruption and replaces the corrupted file with the backup.
pair_dictionary.json A file containing the training queue as well as the on disk location of the most recently trained model.
sub-train-*_TIMESTAMP A folder containing all the files associated with a single model, such as:
*_metadata.json - Metadata for the model, such as normalization max/min, expected training feature list, etc.
*_model.* - The model file saved to disk for reloading from a crash. Can be joblib (typical boosting libs), zip (stable_baselines), hd5 (keras type), etc.
*_pca_object.pkl - The Principal component analysis (PCA) transform (if principal_component_analysis: True is set in the config) which will be used to transform unseen prediction features.
*_svm_model.pkl - The Support Vector Machine (SVM) model (if use_SVM_to_remove_outliers: True is set in the config) which is used to detect outliers in unseen prediction features.
*_trained_df.pkl - The dataframe containing all the training features used to train the identifier model. This is used for computing the Dissimilarity Index (DI) and can also be used for post-processing.
*_trained_dates.df.pkl - The dates associated with the trained_df.pkl, which is useful for post-processing.

The example file structure would look like this:

├── models
│   └── unique-id
│       ├── config_freqai.example.json
│       ├── historic_predictions.backup.pkl
│       ├── historic_predictions.pkl
│       ├── pair_dictionary.json
│       ├── sub-train-1INCH_1662821319
│       │   ├── cb_1inch_1662821319_metadata.json
│       │   ├── cb_1inch_1662821319_model.joblib
│       │   ├── cb_1inch_1662821319_pca_object.pkl
│       │   ├── cb_1inch_1662821319_svm_model.joblib
│       │   ├── cb_1inch_1662821319_trained_dates_df.pkl
│       │   └── cb_1inch_1662821319_trained_df.pkl
│       ├── sub-train-1INCH_1662821371
│       │   ├── cb_1inch_1662821371_metadata.json
│       │   ├── cb_1inch_1662821371_model.joblib
│       │   ├── cb_1inch_1662821371_pca_object.pkl
│       │   ├── cb_1inch_1662821371_svm_model.joblib
│       │   ├── cb_1inch_1662821371_trained_dates_df.pkl
│       │   └── cb_1inch_1662821371_trained_df.pkl
│       ├── sub-train-ADA_1662821344
│       │   ├── cb_ada_1662821344_metadata.json
│       │   ├── cb_ada_1662821344_model.joblib
│       │   ├── cb_ada_1662821344_pca_object.pkl
│       │   ├── cb_ada_1662821344_svm_model.joblib
│       │   ├── cb_ada_1662821344_trained_dates_df.pkl
│       │   └── cb_ada_1662821344_trained_df.pkl
│       └── sub-train-ADA_1662821399
│           ├── cb_ada_1662821399_metadata.json
│           ├── cb_ada_1662821399_model.joblib
│           ├── cb_ada_1662821399_pca_object.pkl
│           ├── cb_ada_1662821399_svm_model.joblib
│           ├── cb_ada_1662821399_trained_dates_df.pkl
│           └── cb_ada_1662821399_trained_df.pkl