namespace not loaded in clojure pedestal

Question

I am using the beginner guide in the pedestal guide but when trying to use use a namespace (require 'test) I get the following error messge: “Execution error (FileNotFoundException) at user/eval2012 (REPL:1). Could not locate test__init.class, test.clj or test.cljc on classpath.”

The same thing happens when trying (require 'hello)

I am using lein repl.

I have a directory called test and under src theres is a file called test.clj

test/src/test.clj:

(ns test
(:require [io.pedestal.http :as http]
[io.pedesteal.http.route :as route]))

test/src/hello.clj:

(defn respond-hello [request]
{:status 200 :body “Herllo world”})

any ideas?

test/deps.edn:

:deps                                                
 {io.pedestal/pedestal.service {:mvn/version "0.5.7"}
  io.pedestal/pedestal.route   {:mvn/version "0.5.7"}
  io.pedestal/pedestal.jetty   {:mvn/version "0.5.7"}
  org.slf4j/slf4j-simple       {:mvn/version "1.7.28"}}
 :paths ["src"]}

To be sure, you would have to show us your file/directory structures and your project.clj, but at first glance: If these are supposed to be tests, there usually is no `src` under the `test` dir - same for hello, but this lacks the `ns`? — cfrick, Mar 19 '21 at 12:02
there is no project.clj, I am just following the pedestal tutorial. the file structucture is shown above, i.e: test/src/test.clj and test/src/hello.clj. the name test is jut arbitary, it has nothing to do with any test. I added deps.edn above — Jonas Fredriksson, Mar 19 '21 at 12:27
Then you should not use `lein repl`? It will not find the files, if you configure things for the clojure cli tools. so the first level of `test` in your directory structure is the name of your project then and you are actually using all those tools inside it? For future reference: don't do that in questions - it confuses people (like me) - just assume the project root. — cfrick, Mar 19 '21 at 12:32

score 2 · Accepted Answer · answered Mar 19 '21 at 22:04

The clj repl differs from lein repl. To use lein repl, you need a project.clj file.

I went through Pedestal's beginner guide successfully using the suggested clj, but I got your error when using lein repl:

user=> (require 'test)
Execution error (FileNotFoundException) at user/eval2006 (REPL:1).

user=> (require 'hello)
Execution error (FileNotFoundException) at user/eval2008 (REPL:1).
Could not locate hello__init.class, hello.clj or hello.cljc on classpath.

I looked at the difference between a clj project and a Leiningen project, and here's what I see:

clj uses deps.edn. Leiningen puts the dependencies in project.clj
clj has :paths ["src"]. Leiningen has :main and :target-path in project.clj

So to switch from clj to lein repl, I added the project.clj file with this:

(defproject pedestal "0.1.0-SNAPSHOT"
  :dependencies [[org.clojure/clojure "1.10.1"]
                 [io.pedestal/pedestal.service "0.5.7"]
                 [io.pedestal/pedestal.route "0.5.7"]
                 [io.pedestal/pedestal.jetty "0.5.7"]]
  :main ^:skip-aot test
  :target-path "target/%s")

which follows my directory structure...

.../pedestal/src/test.clj
.../pedestal/project.clj
.../...

When I started it again, I didn't even need (require 'test) nor even(test/start). (start) did the trick, and the page would load

Leiningen differs from barebones clj tool. It points to starting files(?) differently and pulls in dependencies differently than a barebones clj project, which the guide recommended.

From your question, I don't see mention of a project.clj, so maybe this is what you need.

namespace not loaded in clojure pedestal

1 Answers1