Seattle Example

Datomic distribution has a great sample maintained by Seattle user group. This document explains how to run the Seattle example on Diametric gem. This document assumes Peer-based API on JRuby. REST-API is a subset of Peer API and some of methods using here are not supported.

1. Schema definition

   class Seattle
     include Diametric::Entity
     include Diametric::Persistence::Peer
   
     attribute :name, String, :cardinality => :one, :fulltext => true, :doc => "A community's name"
     attribute :url, String, :cardinality => :one, :doc => "A community's url"
     attribute :neighborhood, Ref, :cardinality => :one, :doc => "A community's neighborhood"
     attribute :category, String, :cardinality => :many, :fulltext => true, :doc => "All community categories"
     attribute :orgtype, Ref, :cardinality => :one, :doc => "A community orgtype enum value"
     attribute :type, Ref, :cardinality => :one, :doc => "A community type enum value"
     enum :orgtype, [:community, :commercial, :nonprofit, :personal]
     enum :type, [:email_list, :twitter, :facebook_page, :blog, :website, :wiki, :myspace, :ning]
   end
   
   class Neighborhood
     include Diametric::Entity
     include Diametric::Persistence::Peer
   
     attribute :name, String, :cardinality => :one, :unique => :identity, :doc => "A unique neighborhood name(upsertable)"
     attribute :district, Ref, :cardinality => :one, :doc => "A neighborhood's district"
   end
   
   class District
     include Diametric::Entity
     include Diametric::Persistence::Peer
   
     attribute :name, String, :cardinality => :one, :unique => :identity, :doc => "A unique district name (upsertable)"
     attribute :region, Ref, :cardinality => :one, :doc => "A district region enum value"
     enum :region, [:n, :ne, :e, :se, :s, :sw, :w, :nw]
   end

   This definitions is equivalent to Datomic schema below:

   [
    ;; seattle
   
    {:db/id #db/id[:db.part/db]
     :db/ident :seattle/name
     :db/valueType :db.type/string
     :db/cardinality :db.cardinality/one
     :db/fulltext true
     :db/doc "A community's name"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :seattle/url
     :db/valueType :db.type/string
     :db/cardinality :db.cardinality/one
     :db/doc "A community's url"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :seattle/neighborhood
     :db/valueType :db.type/ref
     :db/cardinality :db.cardinality/one
     :db/doc "A community's neighborhood"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :seattle/category
     :db/valueType :db.type/string
     :db/cardinality :db.cardinality/many
     :db/fulltext true
     :db/doc "All community categories"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :seattle/orgtype
     :db/valueType :db.type/ref
     :db/cardinality :db.cardinality/one
     :db/doc "A community orgtype enum value"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :seattle/type
     :db/valueType :db.type/ref
     :db/cardinality :db.cardinality/one
     :db/doc "A community type enum value"
     :db.install/_attribute :db.part/db}
   
    ;; community/org-type enum values
    [:db/add #db/id[:db.part/user] :db/ident :seattle.orgtype/community]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.orgtype/commercial]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.orgtype/nonprofit]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.orgtype/personal]
   
    ;; community/type enum values
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/email-list]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/twitter]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/facebook-page]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/blog]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/website]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/wiki]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/myspace]
    [:db/add #db/id[:db.part/user] :db/ident :seattle.type/ning]
   
    ;; neighborhood
    {:db/id #db/id[:db.part/db]
     :db/ident :neighborhood/name
     :db/valueType :db.type/string
     :db/cardinality :db.cardinality/one
     :db/unique :db.unique/identity
     :db/doc "A unique neighborhood name (upsertable)"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :neighborhood/district
     :db/valueType :db.type/ref
     :db/cardinality :db.cardinality/one
     :db/doc "A neighborhood's district"
     :db.install/_attribute :db.part/db}
   
    ;; district
    {:db/id #db/id[:db.part/db]
     :db/ident :district/name
     :db/valueType :db.type/string
     :db/cardinality :db.cardinality/one
     :db/unique :db.unique/identity
     :db/doc "A unique district name (upsertable)"
     :db.install/_attribute :db.part/db}
   
    {:db/id #db/id[:db.part/db]
     :db/ident :district/region
     :db/valueType :db.type/ref
     :db/cardinality :db.cardinality/one
     :db/doc "A district region enum value"
     :db.install/_attribute :db.part/db}
   
    ;; district/region enum values
    [:db/add #db/id[:db.part/user] :db/ident :district.region/n]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/ne]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/e]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/se]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/s]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/sw]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/w]
    [:db/add #db/id[:db.part/user] :db/ident :district.region/nw]
    ]