register Crate in Metabase

src/metabase/driver/crate.clj

+(ns metabase.driver.crate
+  (:require [metabase.driver :as driver]
+            [metabase.driver.generic-sql :as sql]
+            [clojure.string :as s])
+  (:import (clojure.lang Named)))
+
+(defrecord CrateDriver []
+  Named
+  (getName [_] "Crate"))
+
+
+(defn- crate-spec
+  [{:keys [host port]
+    :or {host "localhost", port 4300}
+    :as opts}]
+  (merge {:classname "io.crate.client.jdbc.CrateDriver" ; must be in classpath
+          :subprotocol "crate"
+          :subname (str "//" host ":" port)}
+         (dissoc opts :host :port)))
+
+(defn- connection-details->spec [_ details]
+  (-> details crate-spec))
+
+(def CrateISQLDriverMixin
+  "Implementations of `ISQLDriver` methods for `PostgresDriver`."
+  (merge (sql/ISQLDriverDefaultsMixin)
+         {:connection-details->spec  connection-details->spec}))
+
+(extend CrateDriver
+  driver/IDriver
+  (merge (sql/IDriverSQLDefaultsMixin)
+         {:details-fields (constantly [{:name         "host"
+                                        :display-name "Host"
+                                        :default      "localhost"}
+                                       {:name         "port"
+                                        :display-name "Port"
+                                        :type         :integer
+                                        :default      4300}])
+          })
+  sql/ISQLDriver CrateISQLDriverMixin)
+
+(driver/register-driver! :crate (CrateDriver.))

test/metabase/test/data/crate.clj

+(ns metabase.test.data.crate
+  "Code for creating / destroying a Crate database from a `DatabaseDefinition`."
+  (:require metabase.driver.crate
+            (metabase.test.data [generic-sql :as generic]
+                                [interface :as i]))
+  (:import metabase.driver.crate.CrateDriver))
+
+(defn- database->connection-details [_]
+  (merge {:host         "localhost"
+          :port         4300}))
+
+(extend CrateDriver
+  generic/IGenericSQLDatasetLoader
+  (merge generic/DefaultsMixin
+         {})
+  i/IDatasetLoader
+  (merge generic/IDatasetLoaderMixin
+         {:database->connection-details database->connection-details
+          :engine                       (constantly :crate)}))