A Ruby gem for interacting with Datomic through Flare.
This is not an official Datomic project or documentation and it is not affiliated with Datomic in any way.
gem 'datomic-flare', '~> 1.0.1'
require 'datomic-flare'
client = Flare.new(credentials: { address: 'http://localhost:3042' })
client.dsl.transact_schema!(
{
book: {
title: { type: :string, doc: 'The title of the book.' },
genre: { type: :string, doc: 'The genre of the book.' }
}
}
)
client.dsl.assert_into!(
:book,
{
title: 'The Tell-Tale Heart',
genre: 'Horror'
}
)
client.dsl.query(
datalog: <<~EDN
[:find ?e ?title ?genre
:where [?e :book/title ?title]
[?e :book/genre ?genre]]
EDN
)
[[4611681620380877802, 'The Tell-Tale Heart', 'Horror']]
require 'datomic-flare'
client = Flare.new(credentials: { address: 'http://localhost:3042' })
client.meta
{
'meta' =>
{
'at' => '2024-10-06T13:17:38.761128603Z',
'mode' => 'peer',
'took' => { 'milliseconds' => 0.500799 }
},
'data' =>
{
'mode' => 'peer',
'datomic-flare' => '1.0.0',
'org.clojure/clojure' => '1.12.0',
'com.datomic/peer' => '1.0.7187',
'com.datomic/client-pro' => '1.0.81'
}
}
It provides a Ruby-familiar approach to working with Datomic. It brings Ruby’s conventions and idioms while preserving Datomic’s data-first principles and terminology.
This approach should be cozy to those who are familiar with Ruby.
Learn more about Ruby and The Rails Doctrine:
client.dsl.create_database!('radioactive')
true
client.dsl.destroy_database!('radioactive')
true
client.dsl.databases
['my-datomic-database']
Like CREATE TABLE
in SQL databases or defining document or record structures in other databases.
client.dsl.transact_schema!(
{
book: {
title: { type: :string, doc: 'The title of the book.' },
genre: { type: :string, doc: 'The genre of the book.' },
published_at_year: { type: :long, doc: 'The year the book was first published.' }
}
}
)
true
Like SHOW COLUMNS FROM
in SQL databases or checking document or record structures in other databases.
client.dsl.schema
{
book: {
published_at_year: {
type: :long,
cardinality: :one,
doc: 'The year the book was first published.',
unique: false,
index: false,
history: true
},
title: {
type: :string,
cardinality: :one,
doc: 'The title of the book.',
unique: false,
index: false,
history: true
},
genre: {
type: :string,
cardinality: :one,
doc: 'The genre of the book.',
unique: false,
index: false,
history: true
}
}
}
Like INSERT INTO
in SQL databases or creating a new document or record in other databases.
client.dsl.assert_into!(
:book,
{
title: 'Pride and Prejudice',
genre: 'Romance',
published_at_year: 1813
}
)
4611681620380877802
client.dsl.assert_into!(
:book,
[{
title: 'Near to the Wild Heart',
genre: 'Novel',
published_at_year: 1943
},
{
title: 'A Study in Scarlet',
genre: 'Detective',
published_at_year: 1887
},
{
title: 'The Tell-Tale Heart',
genre: 'Horror',
published_at_year: 1843
}]
)
[4611681620380877804, 4611681620380877805, 4611681620380877806]
Like SELECT
in SQL databases or querying documents or records in other databases.
client.dsl.find_by_entity_id(4611681620380877804)
{
book: {
title: 'Near to the Wild Heart',
genre: 'Novel',
published_at_year: 1943,
_id: 4611681620380877804
}
}
Like SELECT
in SQL databases or querying documents or records in other databases.
client.dsl.query(
datalog: <<~EDN
[:find ?e ?title ?genre ?year
:where [?e :book/title ?title]
[?e :book/genre ?genre]
[?e :book/published_at_year ?year]]
EDN
)
[[4611681620380877805, 'A Study in Scarlet', 'Detective', 1887],
[4611681620380877804, 'Near to the Wild Heart', 'Novel', 1943],
[4611681620380877806, 'The Tell-Tale Heart', 'Horror', 1843],
[4611681620380877802, 'Pride and Prejudice', 'Romance', 1813]]
client.dsl.query(
params: ['The Tell-Tale Heart'],
datalog: <<~EDN
[:find ?e ?title ?genre ?year
:in $ ?title
:where [?e :book/title ?title]
[?e :book/genre ?genre]
[?e :book/published_at_year ?year]]
EDN
)
[[4611681620380877806, 'The Tell-Tale Heart', 'Horror', 1843]]
Like UPDATE
in SQL databases or updating documents or records in other databases. However, Datomic never updates data. It is an immutable database that only accumulates new facts or retracts past facts.
client.dsl.assert_into!(
:book, { _id: 4611681620380877806, genre: 'Gothic' }
)
4611681620380877806
Like DELETE
in SQL databases or deleting documents or records in other databases. However, Datomic never deletes data. It is an immutable database that only accumulates new facts or retracts past facts.
Retract the value of an attribute:
client.dsl.retract_from!(
:book, { _id: 4611681620380877806, genre: 'Gothic' }
)
true
Retract an attribute:
client.dsl.retract_from!(
:book, { _id: 4611681620380877804, genre: nil }
)
true
Retract an entity:
client.dsl.retract_from!(
:book, { _id: 4611681620380877805 }
)
true
It provides methods that mirror Datomic's APIs. Most interactions use EDN, closely following Datomic’s documentation.
This approach should be familiar to those who know Datomic concepts and APIs.
Learn more about Clojure and Datomic:
client.api.create_database!({ name: 'fireball' })['data']
true
client.api.delete_database!({ name: 'fireball' })['data']
true
# Flare on Peer Mode
client.api.get_database_names['data']
# Flare on Client Mode
client.api.list_databases['data']
['my-datomic-database']
client.api.transact!(
{ data: <<~EDN
[{:db/ident :book/title
:db/valueType :db.type/string
:db/cardinality :db.cardinality/one
:db/doc "The title of the book."}
{:db/ident :book/genre
:db/valueType :db.type/string
:db/cardinality :db.cardinality/one
:db/doc "The genre of the book."}
{:db/ident :book/published_at_year
:db/valueType :db.type/long
:db/cardinality :db.cardinality/one
:db/doc "The year the book was first published."}]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@7978603f',
'db-after' => 'datomic.db.Db@359875e3',
'tx-data' =>
[[13194139534312, 50, '2024-10-06T13:17:38.945Z', 13194139534312, true],
[72, 10, ':book/title', 13194139534312, true],
[72, 40, 23, 13194139534312, true],
[72, 41, 35, 13194139534312, true],
[72, 62, 'The title of the book.', 13194139534312, true],
[73, 10, ':book/genre', 13194139534312, true],
[73, 40, 23, 13194139534312, true],
[73, 41, 35, 13194139534312, true],
[73, 62, 'The genre of the book.', 13194139534312, true],
[74, 10, ':book/published_at_year', 13194139534312, true],
[74, 40, 22, 13194139534312, true],
[74, 41, 35, 13194139534312, true],
[74, 62, 'The year the book was first published.', 13194139534312, true],
[0, 13, 72, 13194139534312, true],
[0, 13, 73, 13194139534312, true],
[0, 13, 74, 13194139534312, true]],
'tempids' =>
{
'-9223300668110597923' => 72,
'-9223300668110597922' => 73,
'-9223300668110597921' => 74
}
}
client.api.q(
{
inputs: [{ database: { latest: true } }],
query: <<~EDN
[:find
?e ?ident ?value_type ?cardinality ?doc
?unique ?index ?no_history
:in $
:where
[?e :db/ident ?ident]
[?e :db/valueType ?value_type_id]
[?value_type_id :db/ident ?value_type]
[?e :db/cardinality ?cardinality_id]
[?cardinality_id :db/ident ?cardinality]
[(get-else $ ?e :db/doc "") ?doc]
[(get-else $ ?e :db/unique -1) ?unique_id]
[(get-else $ ?unique_id :db/ident false) ?unique]
[(get-else $ ?e :db/index false) ?index]
[(get-else $ ?e :db/noHistory false) ?no_history]]
EDN
}
)['data'].filter do |datom|
!%w[
db
db.alter db.attr db.bootstrap db.cardinality db.entity db.excise
db.fn db.install db.lang db.part db.sys db.type db.unique
fressian
].include?(datom[1].split('/').first)
end
[[74,
'book/published_at_year',
'db.type/long',
'db.cardinality/one',
'The year the book was first published.',
false,
false,
false],
[72,
'book/title',
'db.type/string',
'db.cardinality/one',
'The title of the book.',
false,
false,
false],
[73,
'book/genre',
'db.type/string',
'db.cardinality/one',
'The genre of the book.',
false,
false,
false]]
client.api.transact!(
{ data: <<~EDN
[{:db/id -1
:book/title "Pride and Prejudice"
:book/genre "Romance"
:book/published_at_year 1813}]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@1fd69b02',
'db-after' => 'datomic.db.Db@fb09bc2',
'tx-data' =>
[[13194139534313, 50, '2024-10-06T13:17:39.060Z', 13194139534313, true],
[4611681620380877802, 72, 'Pride and Prejudice', 13194139534313, true],
[4611681620380877802, 73, 'Romance', 13194139534313, true],
[4611681620380877802, 74, 1813, 13194139534313, true]],
'tempids' => { '-1' => 4611681620380877802 }
}
client.api.transact!(
{ data: <<~EDN
[{:db/id -1
:book/title "Near to the Wild Heart"
:book/genre "Novel"
:book/published_at_year 1943}
{:db/id -2
:book/title "A Study in Scarlet"
:book/genre "Detective"
:book/published_at_year 1887}
{:db/id -3
:book/title "The Tell-Tale Heart"
:book/genre "Horror"
:book/published_at_year 1843}]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@35f37b93',
'db-after' => 'datomic.db.Db@43b227a3',
'tx-data' =>
[[13194139534315, 50, '2024-10-06T13:17:39.105Z', 13194139534315, true],
[4611681620380877804, 72, 'Near to the Wild Heart', 13194139534315, true],
[4611681620380877804, 73, 'Novel', 13194139534315, true],
[4611681620380877804, 74, 1943, 13194139534315, true],
[4611681620380877805, 72, 'A Study in Scarlet', 13194139534315, true],
[4611681620380877805, 73, 'Detective', 13194139534315, true],
[4611681620380877805, 74, 1887, 13194139534315, true],
[4611681620380877806, 72, 'The Tell-Tale Heart', 13194139534315, true],
[4611681620380877806, 73, 'Horror', 13194139534315, true],
[4611681620380877806, 74, 1843, 13194139534315, true]],
'tempids' =>
{
'-1' => 4611681620380877804,
'-2' => 4611681620380877805,
'-3' => 4611681620380877806
}
}
client.api.entity(
{
database: { latest: true },
id: 4611681620380877804
}
)['data']
{
':book/title' => 'Near to the Wild Heart',
':book/genre' => 'Novel',
':book/published_at_year' => 1943,
':db/id' => 4611681620380877804
}
client.api.q(
{
inputs: [{ database: { latest: true } }],
query: <<~EDN
[:find ?e ?title ?genre ?year
:where [?e :book/title ?title]
[?e :book/genre ?genre]
[?e :book/published_at_year ?year]]
EDN
}
)['data']
[[4611681620380877805, 'A Study in Scarlet', 'Detective', 1887],
[4611681620380877804, 'Near to the Wild Heart', 'Novel', 1943],
[4611681620380877806, 'The Tell-Tale Heart', 'Horror', 1843],
[4611681620380877802, 'Pride and Prejudice', 'Romance', 1813]]
client.api.q(
{
inputs: [
{ database: { latest: true } },
'The Tell-Tale Heart'
],
query: <<~EDN
[:find ?e ?title ?genre ?year
:in $ ?title
:where [?e :book/title ?title]
[?e :book/genre ?genre]
[?e :book/published_at_year ?year]]
EDN
}
)['data']
[[4611681620380877806, 'The Tell-Tale Heart', 'Horror', 1843]]
client.api.transact!(
{ data: <<~EDN
[{:db/id 4611681620380877806 :book/genre "Gothic"}]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@6817aa5c',
'db-after' => 'datomic.db.Db@63f25217',
'tx-data' =>
[[13194139534319, 50, '2024-10-06T13:17:39.322Z', 13194139534319, true],
[4611681620380877806, 73, 'Gothic', 13194139534319, true],
[4611681620380877806, 73, 'Horror', 13194139534319, false]],
'tempids' => {}
}
Retract the value of an attribute:
client.api.transact!(
{ data: <<~EDN
[[:db/retract 4611681620380877806 :book/genre "Gothic"]]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@4d739219',
'db-after' => 'datomic.db.Db@7f38a06d',
'tx-data' =>
[[13194139534320, 50, '2024-10-06T13:17:39.385Z', 13194139534320, true],
[4611681620380877806, 73, 'Gothic', 13194139534320, false]],
'tempids' => {}
}
Retract an attribute:
client.api.transact!(
{ data: <<~EDN
[[:db/retract 4611681620380877804 :book/genre]]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@71ff51fa',
'db-after' => 'datomic.db.Db@75c0cb1d',
'tx-data' =>
[[13194139534321, 50, '2024-10-06T13:17:39.428Z', 13194139534321, true],
[4611681620380877804, 73, 'Novel', 13194139534321, false]],
'tempids' => {}
}
Retract an entity:
client.api.transact!(
{ data: <<~EDN
[[:db/retractEntity 4611681620380877805]]
EDN
}
)['data']
{
'db-before' => 'datomic.db.Db@30c25bc1',
'db-after' => 'datomic.db.Db@a43be7c',
'tx-data' =>
[[13194139534322, 50, '2024-10-06T13:17:39.471Z', 13194139534322, true],
[4611681620380877805, 72, 'A Study in Scarlet', 13194139534322, false],
[4611681620380877805, 73, 'Detective', 13194139534322, false],
[4611681620380877805, 74, 1887, 13194139534322, false]],
'tempids' => {}
}
bundle
rubocop -A
gem build datomic-flare.gemspec
gem signin
gem push datomic-flare-1.0.1.gem
Tests run against real Datomic databases, and documentation (README) is generated by interacting with real Datomic databases.
To accomplish that, we need to have Datomic and Flare running.
TL;DR:
git clone https://github.com/gbaptista/datomic-pro-docker.git
cd datomic-pro-docker
cp compose/datomic-flare-dev.yml docker-compose.yml
docker compose up -d datomic-storage
docker compose run datomic-tools psql \
-h datomic-storage \
-U datomic-user \
-d my-datomic-storage \
-c 'CREATE TABLE datomic_kvs (
id TEXT NOT NULL,
rev INTEGER,
map TEXT,
val BYTEA,
CONSTRAINT pk_id PRIMARY KEY (id)
);'
docker compose up -d datomic-transactor
docker compose run datomic-tools clojure -M -e "$(cat <<'CLOJURE'
(require '[datomic.api :as d])
(d/create-database "datomic:sql://my-datomic-database?jdbc:postgresql://datomic-storage:5432/my-datomic-storage?user=datomic-user&password=unsafe")
(d/create-database "datomic:sql://my-datomic-database-test?jdbc:postgresql://datomic-storage:5432/my-datomic-storage?user=datomic-user&password=unsafe")
(d/create-database "datomic:sql://my-datomic-database-test-green?jdbc:postgresql://datomic-storage:5432/my-datomic-storage?user=datomic-user&password=unsafe")
(System/exit 0)
CLOJURE
)"
docker compose up -d datomic-peer-server
docker compose up -d datomic-flare-peer datomic-flare-client
curl -s http://localhost:3042/meta \
-X GET \
-H "Content-Type: application/json" \
| jq
{
"data": {
"mode": "peer"
}
}
curl -s http://localhost:3043/meta \
-X GET \
-H "Content-Type: application/json" \
| jq
{
"data": {
"mode": "client"
}
}
You are ready to run tests and generate documentation.
Detailed instructions:
Clone the datomic-pro-docker repository and copy the Docker Compose template:
git clone https://github.com/gbaptista/datomic-pro-docker.git
cd datomic-pro-docker
cp compose/datomic-flare-dev.yml docker-compose.yml
Start PostgreSQL as Datomic's storage service:
docker compose up -d datomic-storage
docker compose logs -f datomic-storage
Create the table for Datomic databases:
docker compose run datomic-tools psql \
-h datomic-storage \
-U datomic-user \
-d my-datomic-storage \
-c 'CREATE TABLE datomic_kvs (
id TEXT NOT NULL,
rev INTEGER,
map TEXT,
val BYTEA,
CONSTRAINT pk_id PRIMARY KEY (id)
);'
You will be prompted for a password, which is unsafe
.
Start the Datomic Transactor:
docker compose up -d datomic-transactor
docker compose logs -f datomic-transactor
Create the following databases:
my-datomic-database
my-datomic-database-test
my-datomic-database-test-green
docker compose run datomic-tools clojure -M -e "$(cat <<'CLOJURE'
(require '[datomic.api :as d])
(d/create-database "datomic:sql://my-datomic-database?jdbc:postgresql://datomic-storage:5432/my-datomic-storage?user=datomic-user&password=unsafe")
(d/create-database "datomic:sql://my-datomic-database-test?jdbc:postgresql://datomic-storage:5432/my-datomic-storage?user=datomic-user&password=unsafe")
(d/create-database "datomic:sql://my-datomic-database-test-green?jdbc:postgresql://datomic-storage:5432/my-datomic-storage?user=datomic-user&password=unsafe")
(System/exit 0)
CLOJURE
)"
Start the Peer Server:
docker compose up -d datomic-peer-server
docker compose logs -f datomic-peer-server
Start 2 instances of Flare, one in Peer Mode and another in Client Mode:
docker compose up -d datomic-flare-peer datomic-flare-client
docker compose logs -f datomic-flare-peer
docker compose logs -f datomic-flare-client
You should be able to request both:
Flare in Peer Mode:
curl -s http://localhost:3042/meta \
-X GET \
-H "Content-Type: application/json" \
| jq
{
"data": {
"mode": "peer"
}
}
Flare in Client Mode:
curl -s http://localhost:3043/meta \
-X GET \
-H "Content-Type: application/json" \
| jq
{
"data": {
"mode": "client"
}
}
You are ready to run tests and generate documentation.
Tests run against real Datomic databases, so complete the Setup for Tests and Documentation first.
cp .env.example .env
bundle exec rspec
Documentation (README) is generated by interacting with real Datomic databases, so complete the Setup for Tests and Documentation first.
Update the docs/templates/*.md
files, and then:
cp .env.example .env
bundle exec ruby ports/cli.rb docs:generate
Trick for automatically updating the README.md
when docs/templates/*.md
files change:
sudo pacman -S inotify-tools # Arch / Manjaro
sudo apt-get install inotify-tools # Debian / Ubuntu / Raspberry Pi OS
sudo dnf install inotify-tools # Fedora / CentOS / RHEL
while inotifywait -e modify docs/templates/*; \
do bundle exec ruby ports/cli.rb docs:generate; \
done
Trick for Markdown Live Preview:
pip install -U markdown_live_preview
mlp README.md -p 8042 --no-follow