
Collimator
Collimator is a JavaScript library that uses reflection techniques to introspect PostgreSQL databases:
- Enumerate table names and identify primary keys
- Generate JSON Schema v4 for a given table
- Extract table relationship information using foreign key constraints
Why?
Traditionally, programmers have defined their schema by writing model definitions in application code. Some kind of migration tool then transforms this schema into SQL, and applies it against a database.
Collimator allows this pattern to be reversed. The database now becomes the canonical source of your application's schema and relationship metadata.
Prior Art
The approach to schema extraction is inspired by DDL.js. Collimator's implementation is currently not as robust as DDL.js, and only targets PostgreSQL (an intentional design decision, and unlikely to change). However, Collimator supports the extraction of relationship information.
Installation
Install as a dependency in your application with npm install --save collimator
.
Usage
Enumerate table names and primary keys with collimator.tables(db)
.
Generate JSON Schema with collimator.schema(db, 'tableName')
.
Extract relationship information with collimator.relationships(db, 'tableName')
.
The top-level Collimator functions (tables
, schema
and relationships
) accept a pg-promise connection as their first argument, and return a promise. For further guidance, please refer to the examples and API Documentation.
Change Log
Please consult the Change Log for detailed notes on each release.
Development
Install dependencies with:
npm install
Run the tests with:
gulp
Run unit test coverage with:
gulp coverage
Update API documentation with:
gulp docs
Enter development mode with:
gulp dev
This will watch the src
and spec
directories and run gulp
automatically when a change is detected. Note that it will not run the tests until it detects a change, so you may prefer to run it with gulp & gulp dev
.