Trouble connecting to postgresql DB on Heroku with Korma (Clojure)

Question

I am parsing the postgresql uri in my config settings on Heroku. But I cannot seem to get it working. Any help would be greatly appreciated, I'm probably missing something straight forward.

Here is the code used.

(def dev-db-info
  {:db "dbname"
   :user "username"})

(defn parse-db-uri
  [uri]
  (drop 1 (split uri #"://|:|@|/")))

(defn create-map-from-uri
  [uri]
  (let [parsed (parse-db-uri uri)]
  (zipmap [:user :password :host :port :db] parsed)))

(defn db-info
  []
  (if production?
    (create-map-from-uri (System/getenv "DATABASE_URL"))
    dev-db-info))

(defdb connected-db
   (postgres (db-info)))

The map I retrieve from the uri looks like this:

{:db "dbname"
 :port "5662"
 :host "ec2-url.compute-1.amazonaws.com"
 :password "pwd"
 :user "username"}

I get the following error:

Connections could not be acquired from the underlying database!

EDIT:

I have since given up on using Korma, and switched to using Clojure.JDBC 0.2.3 which supports "connection-uri" and therefore ssl connections to the db. Korma doesn't currently support this. I will file an issue on Github to allow this connection method.

Answer 1

EDIT: There's no reason to use [org.clojars.ccfontes/korma "0.3.0-beta12-pgssl"] anymore. Read this to know more about it. Also, please ignore the following instructions.

Added postgres SSL support.

In project.clj insert: [org.clojars.ccfontes/korma "0.3.0-beta12-pgssl"]

Defining a connection to a postgres database on heroku:

(ns app.db
    (:require [clojure.java.jdbc :as sql]
              [korma.db :as db]
              [clojure.string :as string])
    (:import (java.net URI)))

    (defn set-app-pg-db! [mode]
      (let [db-uri (java.net.URI. (System/getenv "DATABASE_URL"))]
        (->> (string/split (.getUserInfo db-uri) #":")
          (#(identity {:db (last (string/split (System/getenv "DATABASE_URL") #"\/"))
                       :host (.getHost db-uri)
                       :port (.getPort db-uri)
                       :user (% 0)
                       :password (% 1)
                       :ssl true
                       :sslfactory (when (= mode :dev) "org.postgresql.ssl.NonValidatingFactory")}))
          (db/postgres)
          (db/defdb app-pg-db))))

The fix uses Tomcat JDBC Connection Pool and their configuration sample for the connection pool, so it may not be well suited for everyone's needs, plus this is only a hack. Ideally the original Korma project should integrate these changes or other possible solution.

Would appreciate some feedback from other people since it was only tested in my own project. Thanks.