Create database table ExtractMetadata to store extract files

[mikehgrantsgov]

Related to 2454

Summary

The legacy website provides the ability to download XML extracts of opportunity data: https://www.grants.gov/xml-extract - this is something we should also support. Having extracts (especially if they're just the same data as our search endpoints) reduces the traffic our search endpoint will need to handle as we can point anyone that would want to scrape our data to an extract file.

Create a table to track extract metadata.

Something like:

class ExtractMetadata(Base):
    __tablename__ = 'extract_metadata'

    id = Column(Integer, primary_key=True, autoincrement=True)
    extract_type = Column(String, nullable=False)
    file_name = Column(String, nullable=False)
    file_path = Column(String, nullable=False)
    file_size = Column(Integer, nullable=False)
    created_on = Column(DateTime, server_default=func.now(), nullable=False)
    updated_on = Column(DateTime, server_default=func.now(), onupdate=func.now(), nullable=False)

Acceptance criteria

• Model created
• Database migration generated