I wish there was a "transactor library" as well as a peer library, as an alternative to shipping code as strings to the transactor

a library where you spawn the transactor server yourself, and there's hooks for processing transactions and registering transaction functions

so you can redeploy your transactor service, rather than shipping strings and running code in a "foreign" place

would also allow for transactor functions to be written in any JVM language

@hmaurer - it’s a bit more involved than that 🙂 I know I could do it on the peer, hence my 2nd solution. I’d really like to avoid it though.

@augustl cognitect's advice is to add a jar to the transactor classpath with your code. Then the tx fn impl just calls something from that jar

The problem with these approaches is that it doesn't version code in the same timeline as data

ah, didn't know that was possible, but that makes sense

are there any practical problems with not having the transaction functions in the database, versioning/history/timeline wise?

hello folks - simple question that is annoyingly hard to google…

I have a uri type

I try to add “https:/some-url,.com”

but it blows up

what is the magic to convert this string into a literal URi?

:cause :db.error/wrong-type-for-attribute Value https://some-url.com is not a valid :uri for attribute :person/photo

@raymcdermott (java.net.URI. "")

ok, yes … so no literal?

what do you mean?

#uuid

Datomic’s URIs are java.net.URI instances

ok, thanks

I can move on 🙂

@raymcdermott ah; #uuid is a reader macro which creates an instance of java.util.UUID

e.g.

=> (type #uuid "6c84fb90-12c4-11e1-840d-7b25c5ee775a")
#<Class@6a2f6f80 java.util.UUID>

there does not appear to be a similar reader macro for URIs

yes, indeed. Thanks

bit of a shame but there we are 🙂

you can make one 🙂

it means you cannot put it into an edn file

which is the main drawback

Hey all, I’m running into an odd problem. On my docker container I’m unable to pull datomic-pro yet locally I am. I have set teh following:

:repositories [["" {:url ""
                                    :username [:env/datomic_username]
                                    :password [:env/datomic_password]}]]

@raymcdermott ah if it’s in an EDN file it’s easy

I know I’m doing something stupid, I just can’t figure out what

you can define custom tags when parsing the edn

with the :readers options iirc

@hmaurer I’m gonna have to think about that

This all works fine outside of the container

(clojure.edn/read-string input {:readers {'uri #(new java.net.URI %)}}

nice

@hmaurer I’ll give it a shot, though TBH I find it irksome that the supported data types don’t have reader literals

@raymcdermott these are Datomic’s supported data types. I am not sure why uuid has a reader macro in clojure and URI does not, but you can’t have a reader literal for every type anyway

maybe someone else can elighten us on this

b/c java.net.URI is a disaster

i wouldn’t use the uri datatype @raymcdermott

not sure what using it gets you other than pain 🙂

so uri is not useful in Datomic? Just use strings?

maybe somebody better tell the Datomic team 😉

but I will explain why types are sometimes useful if you insist @robert-stuttaford 😉

goes against the grain though

Anyone have a link to the docs for updating a transactor on aws?

@petr there are several ways to do it, but updating the cloudformation stack through the aws console is probably the easiest http://docs.datomic.com/aws.html#aws-management-console

@stijn I was thinking more in terms of updating the version/cw metrics. Basically the stuff set in the config files

the version is a parameter in the cloudformation stack

i'm not sure about cw metrics though

OH sweet

I didn’t know that

@hmaurer I tried to add my own reader as suggested and now the datomic reader is missing

CompilerException java.lang.RuntimeException: No reader function for tag db/id, compiling:(core.clj:141:25)

is there a way to chain them?

@raymcdermott how are you reading your edn file?

and how were you reading it previously?

(def data-tx (edn/read-string reader-opts (slurp “resources/data.edn”)))

where reader-opts

(def reader-opts {:readers {‘uri #(new java.net.URI %)}})

previously

(def data-tx (read-string (slurp “resources/data.edn”)))

so not using the edn reader

or any opts

I am not too sure how the Datomic library defines the EDN tag literals, so I can’t advise you on how to merge your custom ones. Someone more knowledgeable might be able to answer 🙂

so maybe @robert-stuttaford is right … pure pain … what do you think @alexmiller?

It’s midnight here so I have to go catch my carriage home…. ttyl

well, you can either set up an external data_readers.clj in your project (it should be merged with all others found on the classpath) OR you can explicit bind your own around the reader call

binding *data-readers* that is

(doc *data-readers*) is a good place to start

this and all the related things around it is an area ripe for a guide

I guess I did write some stuff about it at https://clojure.org/reference/reader#tagged_literals

but could use some more exposition and examples

if i’m using lein - what’s the least painful way to get my code on the classpath in a way that datomic db.fn :requires can find it?

this is how i’ve unblocked myself:

(let [cl (.getContextClassLoader (Thread/currentThread))
        dcl (clojure.lang.DynamicClassLoader. cl)]
    (.setContextClassLoader (Thread/currentThread) dcl)
    (add-classpath "file://./src"))

¯\(ツ)/¯