Dev and test locally with dev-local

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What’s the recommended way to use in-memory databases - for automated tests - via the Datomic Client API?

Is that something I could/should do with dev-local?

So far I was using the Peer API for that purpose, but if I want to transition to using the Client API, then I can’t use that approach anymore, can I?

I’m aware of the https://github.com/ComputeSoftware/datomic-client-memdb library, which has been deprecated in favour of dev-local recently, but I don’t see how dev-local serves the in-memory use-case.

According to https://docs.datomic.com/on-prem/peer-server.html, we can start a peer-server, which exposes an in-memory db, but it doesn’t allow my automated test suite to isolate my tests into different, independent in-memory DBs.

I also haven’t found any official way to directly start a temporary peer-server from my application’s process, without shelling out.

I did look into what happens when I bin/run -m datomic.peer-server ..., so I could start a peer-server, but I have no idea how to shut it down.

I’ve added these to deps.edn (where CURRENT is a link to datomic-pro-1.0.6165/):

 :aliases
 {:datomic-peer
  {:extra-paths
   ["CURRENT/resources"
    "CURRENT/datomic-transactor-pro-1.0.6165.jar"
    "CURRENT/lib/*"
    "CURRENT/bin"]}

then I could do the following:

;; Start a Peer Server for convenience
(comment
  ;; Based on
  ;; https://docs.datomic.com/on-prem/getting-started/connect-to-a-database.html
  ;;   bin/run -m peer-server -h localhost -p 8998 \
  ;;           -a myaccesskey,mysecret -d hello,datomic:mem://hello

  (require '[datomic.peer-server :as peer-server]
           '[clojure.tools.cli :as cli])

  @(def peer-server-config
     (-> ["-h" "localhost"
          "-p" "8998"
          "-a" "myaccesskey,mysecret"
          "-d" "hello,datomic:mem://hello"]
         (cli/parse-opts datomic.peer-server/cli-options)))

  @(def peer-server
     (datomic.peer-server/create (:options peer-server-config)))

  )