Re-organize requirements files

[harupy]

Signed-off-by: harupy hkawamura0130@gmail.com

What changes are proposed in this pull request?

Re-organize requirements files to improve the file structure in the repository.

How is this patch tested?

NA

Does this PR change the documentation?

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Release Notes

Is this a user-facing change?

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• Yes. Give a description of this change to be included in the release notes for MLflow users.

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What component(s), interfaces, languages, and integrations does this PR affect?

Components

• area/artifacts: Artifact stores and artifact logging
• area/build: Build and test infrastructure for MLflow
• area/docs: MLflow documentation pages
• area/examples: Example code
• area/model-registry: Model Registry service, APIs, and the fluent client calls for Model Registry
• area/models: MLmodel format, model serialization/deserialization, flavors
• area/projects: MLproject format, project running backends
• area/scoring: MLflow Model server, model deployment tools, Spark UDFs
• area/server-infra: MLflow Tracking server backend
• area/tracking: Tracking Service, tracking client APIs, autologging

Interface

• area/uiux: Front-end, user experience, plotting, JavaScript, JavaScript dev server
• area/docker: Docker use across MLflow's components, such as MLflow Projects and MLflow Models
• area/sqlalchemy: Use of SQLAlchemy in the Tracking Service or Model Registry
• area/windows: Windows support

Language

• language/r: R APIs and clients
• language/java: Java APIs and clients
• language/new: Proposals for new client languages

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• integrations/azure: Azure and Azure ML integrations
• integrations/sagemaker: SageMaker integrations
• integrations/databricks: Databricks integrations

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• rn/feature - A new user-facing feature worth mentioning in the release notes
• rn/bug-fix - A user-facing bug fix worth mentioning in the release notes
• rn/documentation - A user-facing documentation change worth mentioning in the release notes

[liangz1]

LGTM. I agree with this re-org of the files. Because putting the requirements files under dev could confuse the developer to think that dev directory is used for setting up the personal development environment (which is actually used for github workflows).

Only one non-blocking comment about the wording.

[liangz1]

Actually, I find the ordering here a bit annoying. When I read this doc, I follow the order to install ip install -e .[extras] first (in the previous paragraph). After that, I read If you plan on doing development and testing, you will also need to install the following into the conda environment, where it asks you to install requirements/test-requirements.txt first and then extras. The result is, many libs are installed, uninstalled, and reinstalled back and forth (since some requirements have version limitations while others don't).

It would be convenient if you rephrase it to avoid developers installing pip install -e .[extras] first or make the requirements compatible (installing test-requirements.txt should not need to uninstall libs from extras).

[harupy]

@liangz1 Good point. Can we merge these code two blocks into one?

conda create --name mlflow-dev-env python=3.6
conda activate mlflow-dev-env
# installs mlflow from current checkout with packages required for development
pip install -e .[extras] -r requirements/test-requirements.txt
pip install -e tests/resources/mlflow-test-plugin

[liangz1]

I'm not sure whether this will resolve the difficulty, since the audience might still install [extras] first and then have to uninstall the dependencies that do not meet requirements/test-requirements.txt.
Anyways, it just takes a longer time but is correct, so we don't have to spend too much time on it.