Crate ohmers [−] [src]

Object-hash mapping library for Redis.

Ohmers is a library for storing objects in Redis, a persistent key-value database. It is based on the Ruby library Ohm, and it uses the same key names, so it can be used in the same system.

Prerequisites

Have a redis server running and a redis-rs connection.

Getting started

Ohmers maps Rust structs to hash maps in Redis. First define the structs using the model! macro, and then use their methods to created, read, update, delete.


model!(Event {
    indices {
        name:String = "My Event".to_string();
    };
    venue:Reference<Venue> = Reference::new();
    participants:Set<Person> = Set::new();
    votes:Counter = Counter;
});

model!(Venue {
    name:String = "My Venue".to_string();
    events:Set<Event> = Set::new();
});

model!(Person {
    name:String = "A Person".to_string();
});
let p1 = create!(Person { name: "Alice".to_string(), }, &client).unwrap();
let p2 = create!(Person { name: "Bob".to_string(), }, &client).unwrap();
let p3 = create!(Person { name: "Charlie".to_string(), }, &client).unwrap();

let v1 = create!(Venue { name: "Home".to_string(), }, &client).unwrap();
let v2 = create!(Venue { name: "Work".to_string(), }, &client).unwrap();

let mut e1 = create!(Event { name: "Birthday Party".to_string(), }, &client).unwrap();
insert!(e1.participants, p1, &client).unwrap();
insert!(e1.participants, p2, &client).unwrap();
insert!(e1.participants, p3, &client).unwrap();
e1.venue.set(&v1);
e1.save(&client).unwrap();

let mut e2 = create!(Event { name: "Work Meeting".to_string(), }, &client).unwrap();
insert!(e2.participants, p1, &client).unwrap();
insert!(e2.participants, p2, &client).unwrap();
e2.venue.set(&v2);
e2.save(&client).unwrap();

Macros

collection!	Properties declared as `Collection` can use the collection macro to get a `Query` to iterate over all of its elements. A `Collection` is an accessor to objects that have a `Reference` to the object.
contains!	Checks if an element is in a List or a Set.
counter!
create!	Creates a new instance of `$class` using the default properties, overriding specified collection of `$key` with `$value`, and saving it in the database
decr!
find!	Returns a `Query` with all the `$class` objects where `$key` is `$value`. All the `$key` must be declared as `indices` in the `model!` declaration.
first!	Retrieves an element from the beginning of `$obj.$prop`. The property must be a List.
incr!
insert!	Insert `$el` in `$obj.$prop`. The property must be a Set.
last!	Retrieves an element from the end of `$obj.$prop`. The property must be a List.
len!	Number of elements in a List or Set property.
model!	Declares a struct. Fields may be declared as a part of uniques, indices, or regular fields. Every field must have a default value. The struct will derive RustcEncodable, RustcDecodable, and Default. More `derive`s can be specified.
new!	Creates a new instance of `$class` using the default properties, overriding specified collection of `$key` with `$value`.
pop_back!	Retrieves and remove an element from the end of `$obj.$prop`. The property must be a List.
pop_front!	Retrieves and remove an element from the beginning of `$obj.$prop`. The property must be a List.
push_back!	Adds `$el` at the end of `$obj.$prop`. The property must be a List.
push_front!	Adds `$el` at the beginning of `$obj.$prop`. The property must be a List.
remove!	Removes occurences of an element in a List or a Set.
try_iter!	Creates an iterable of all elements in `$obj.$prop`. The property must be a List.
try_range!	Creates an iterable of `$obj.$prop` between `$start` and `$end`. The property must be a List.

Structs

Collection	A wrapper for classes that are referenced from another classes property.
Counter	Atomic counter
Iter	Iterator for query results
List	A list of elements.
Query	A query of a set, or a result of set operations.
Reference	A Reference to another Ohmer object.
Set	An unordered collection of items.

Enums

OhmerError
StalSet	A set of values. It can be generated from a Redis key or from a set operation based on other sets.

Traits

Ohmer

Structs that can be stored in and retrieved from Redis. You can use the model! macro as a helper.

Functions

all	Gets an iterator for all elements.
all_query	Gets a query for all elements.
get	Gets an element by id.
with	Find an element by a unique index.