w-henderson/jasondb

🗄️ A Blazingly-Fast, JSON-Based, Log-Structured Database.

👋 Hi there, I'm William

I'm a Computer Science student at the University of Cambridge with a passion for solving problems by developing efficient, robust and maintainable software, built with performance in mind. I thrive on projects where every millisecond counts, and I find immense satisfaction in delivering performant and reliable solutions across diverse domains, from systems development to web applications, back-end infrastructure to mobile apps.

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jasondb's Issues

JasonDB v0.2 Roadmap

JasonDB v0.2 is a complete rewrite from scratch, replacing the previous dodgy code which has now been placed in the legacy branch. A very bare-bones implementation has been completed, and this issue details the features and fixes needed to flesh it out before we can publish it.

Checklist

• #6
• #7
• #8
• #9
• #10

If any more features come up, they will be added here.

Field `closure` of struct `jasondb::query::PredicateClosure` is private

The closure field of jasondb::query::PredicateClosure is pub(crate), meaning the query! macro cannot be used with closures outside of the crate. This should be changed to pub.

Add support for a `push` method

This would append to the end of the collection and automatically generate an ID which would be chronologically correct. (basically just copying Firebase from this blog post).

Optimise more queries using secondary indexes

Queries that include fields which are indexed can be optimised so they are faster and use less disk operations.

In the table below, fields refers to fields in the query, for example in age >= 18 the field is age. Queries can be combined with a PredicateCombination (and or or) and there can be any number of predicates in a query.

Progress Table

	PredicateCombination::And	PredicateCombination::Or
All fields are the same and indexed	✔️ Optimised in 62b0bc1	✔️ Optimised in 62b0bc1
All fields are indexed	✔️ Optimised in 27174a2	✔️ Optimised in 27174a2
Some fields are indexed	✔️ Optimised in 1e69eb3	❌ Not optimisable
No fields are indexed	❌ Not optimisable	❌ Not optimisable

Optimise the crate generally using profiling

Making a flamegraph would be useful as well as maybe some benchmarks.

Add migration options for changing datatype

This should probably be implemented with a closure mapping one datatype to another.

Potential signature:

impl<T, S> Database<T, S>
where
    T: IntoJson + FromJson,
    S: Source,
{
    pub fn migrate<U, F>(mut self, f: F) -> Result<Database<U, S>, JasonError>
    where
        U: IntoJson + FromJson,
        F: Fn(T) -> U;
}

Add closure-based queries

This would allow even more complex queries to be optimised.

Write inline documentation for the crate

This should also be enforced for the future with #![warn(missing_docs)].

Add more flexible methods for creating and opening databases

Currently, opening a database looks like this:

let source = FileSource::open("my_database.jdb")?;
let mut db: Database<MyStruct> = Database::new(source)?;

This is very inflexible so maybe we should add the following methods:

Database::open_file("my_database.jdb")
Database::create_file("my_database.jdb")
Database::new_file("my_database.jdb")
Database::new_memory()
Database::new_config("my_database.jdb", config_options)