How to check proxy settings in Leiningen ? (Clojure) - clojure

I want to check if Windows ENV variable http_proxy is picked properly by Leiningen. I've found a function get-proxy-settings but can't understand how to call it properly. Seems I have to use namespace leiningen.core.classpath somehow for this?
This is my second day to learn Clojure and I am not familiar with namespaces yet.

Just try your proxy settings in your environment and see if it works. It should work automatically.
But if you must, you can call leiningen.core.classpath/get-proxy-settings from your project definition by using unquote. Minimal example:
(defproject proxy-settings "0.1-SNAPSHOT"
:dependencies [[org.clojure/clojure "1.8.0"]]
:plugins [[lein-pprint "1.1.2"]]
:debug/proxy ~(leiningen.core.classpath/get-proxy-settings))
Note the lein-pprint plugin there.
Use lein pprint to see the value of :debug/proxy.

Related

Could not locate clojure/data/json: How do I get my REPL to see this (and similar) dependencies

I am using lein repl without a project so there is no project.clj.
I am running Leiningen 2.8.1 on Java 1.8.0_191 OpenJDK 64-Bit Server VM.
When I require a Clojure dependency that I assume should just work - like clojure.data.json - I notice that it is not in my .m2 directory. Is that why I am getting a FileNotFoundException Could not locate clojure/data/json__init.class or clojure/data/js
on.clj on classpath? I can't find my other Clojure dependencies there either so I don't know where they reside and if this dependancy should be in .m2 or not.
I understand the error message but without knowing its location or even knowing how to properly add it to the CLASSPATH for the REPL to see it, I remain stuck.
Is this a dependency that I still need to install? If so, how do I install it without going through a project?
I don't understand the JVM as I am new to it, so add a little extra information in your answer.
I have looked at this, this, this, this and this. I don't know if I am overlooking anything so your help will really be appreciated.
I am using lein run without a project so there is no project.clj.
If you're using Leiningen, this'll be much easier if you create a project.clj file that declares your dependencies. Leiningen will read project.clj and handle fetching any missing dependencies to your local Maven repository, and add them to your classpath when you start your REPL/application. (lein run doesn't work for me in a directory without a project.clj; I get an error: No :main namespace specified in project.clj.. Did you mean lein repl?)
When I require a Clojure dependency that I assume should just work - like clojure.data.json - I notice that it is not in my .m2 directory.
clojure.data.json doesn't ship with Clojure — it's a separate dependency that must be fetched and added to your classpath in order to use it. The classpath tells the JVM where to look when it loads class files. Leiningen will do both of these things for you if you declare the dependency in project.clj:
:dependencies [[org.clojure/clojure "1.10.0"]
[org.clojure/data.json "0.2.6"]]
You can also use the lein deps command if you only want to fetch dependencies.
You can create a new/blank Leiningen project with lein new project_name_goes_here. It will have a project.clj with a few boilerplate entries and a :dependencies key where you can declare dependencies.
I understand the error message but without knowing its location or even knowing how to properly add it to the CLASSPATH for the REPL to see it, I remain stuck. Is this a dependency that I still need to install? If so, how do I install it without going through a project?
You could manually download it from the internet, then manually add its path to your classpath, but if you're already using Leiningen it's much easier to add a line to a project.clj file and have Leiningen handle this for you.
If using a project.clj file w/Leiningen isn't an option, there are other ways to use Clojure and resolve dependencies/build a classpath at runtime. Boot accommodates this workflow, you can use Leiningen like this with a little added effort, as well as the newer tools.deps tooling. There are examples of each in this ClojureVerse thread, but note that some of these approaches are doing essentially the same thing as declaring the dependency in a file — instead declaring them as CLI arguments.
For example, using Clojure CLI tooling:
$ clj -Sdeps "{:deps {org.clojure/data.json {:mvn/version \"0.2.6\"}}}"
Clojure 1.9.0
user=> (require '[clojure.data.json :as json])
nil
user=> (json/write-str {:foo "bar"})
"{\"foo\":\"bar\"}"
user=> (System/getProperty "java.class.path")
"src:
/Users/me/.m2/repository/org/clojure/clojure/1.9.0/clojure-1.9.0.jar:
/Users/me/.m2/repository/org/clojure/data.json/0.2.6/data.json-0.2.6.jar:
/Users/me/.m2/repository/org/clojure/spec.alpha/0.1.143/spec.alpha-0.1.143.jar:
/Users/me/.m2/repository/org/clojure/core.specs.alpha/0.1.24/core.specs.alpha-0.1.24.jar"
You could create a deps.edn file containing {:deps {org.clojure/data.json {:mvn/version \"0.2.6\"}}} in the same directory, and clj would read that, resolve the dependencies if necessary, and build the classpath accordingly.
This is a great opportunity to use lein try. Once you add it to your ~/.lein/profiles.clj, you'd simply run: lein try org.clojure/data.json and you'll be greeted with a running REPL with that dependency just a require away.

How do I add a library to LightTable so that when I use instarepl it will always have said library?

I'd like to add certain library dependencies to LightTable as a whole so that when I am messing around learning new stuff, I don't have to create a new project as a whole.
Let's say I want to always have access to these libraries: math.combinatorics and math.numeric-tower.
Lighttable seems to be calling a repl from leinigen, so am I really needing to add something there?
See https://github.com/LightTable/LightTable/blob/master/project.clj
It will be calling a repl of Leiningen. Rather than adding the dependencies to LightTable you could add them to your Leiningen Profile (~/.lein/profiles.clj)
The file would probably look something like this with your dependencies:
{:user {:dependencies [[math.combinatorics "x.x.x"]
[math.numeric-tower "x.x.x"]]}}
Generally this is not a very good idea. It will be a global thing and will probably cause you problems in the future. If you create an application you might find that these two libraries are available when they won't be for other people or on difference computers.
What would be a better option would be to create a new project using Leiningen. You can then edit your project.clj file to look something like this
(defproject math-thing "0.1.0-SNAPSHOT"
:description "FIXME: write description"
:dependencies [[org.clojure/clojure "1.6.0"]
[math.combinatorics "x.x.x"]
[math.numeric-tower "x.x.x"]])
Then when editing your clj file LightTable uses your project.clj file to start instrepl and will resolve any needed dependencies.
Use the leiningen profile e.g. ~/.lein/profiles.clj and define a :injections [ ... ] node which performs the (require '[ ]) and import, refer-clojure and other items you have. I generally prefer to have at least Alembic present in my dev profile (wrapping Maven/Sonatype) so I can download, install in maven then classpath and project reload in one go using a macro/function wrapper around distill* to prevent a long load time due to too many libraries included in the user space. Pretty much this is the only function I usually want present in any REPL or LT InstaRepl and I put development and debugging snippets in project ./dev/user.clj to keep most of the messy stuff project specific.

Using lwjgl in Leiningen/Clojure

Solution
(1) (println (. System getProperty "java.library.path"))
This gives me a list of places java looks for native extensions.
Then, I took the lwjgl native extensions, and put them there.
Things that didn't work for me (probably because I used them incorrectly)
(*) setting :native-path
(*) setting :native-dependencies
Problem
My setup:
(lein deps; echo "====="; cat project.clj; echo "====="; cat src/main.clj; echo "====="; lein repl) &> log
contents of "log"
Copying 10 files to /Volumes/ramdisk/fail/lib
=====
(defproject
mincase "0.0.1"
:dependencies [[org.clojure/clojure "1.4.0"]
[org.lwjgl.lwjgl/lwjgl "2.8.2"] ]
:repositories {"local" "/Users/x/z/maven_repo"}
:jvm-opts ["-Xms4g" "-Xmx4g"]
:repl-init main
)
=====
(ns main
(:import org.lwjgl.opengl.Display))
=====
REPL started; server listening on localhost port 31235
UnsatisfiedLinkError no lwjgl in java.library.path java.lang.ClassLoader.loadLibrary (ClassLoader.java:1860)
clojure.core=>
Note -- I had already done a "lein deps", so the lwjgl library has been pulled into maven. What I don't understand are:
(*) how do I get access to lwjgl from Clojure?
(*) more importantly, how do I debug which step this whole thing has gone wrong at?
$ find lib
lib
lib/clojure-1.4.0.jar
lib/jinput-2.0.5.jar
lib/jinput-platform-2.0.5-natives-linux.jar
lib/jinput-platform-2.0.5-natives-osx.jar
lib/jinput-platform-2.0.5-natives-windows.jar
lib/jutils-1.0.0.jar
lib/lwjgl-2.8.2.jar
lib/lwjgl-platform-2.8.2-natives-linux.jar
lib/lwjgl-platform-2.8.2-natives-osx.jar
lib/lwjgl-platform-2.8.2-natives-windows.jar
So it appears that lwjgl has been pulled in.
What are the steps I should try to figure out which step I went wrong on?
Thanks!
Dropping this note here since google found this post for my similar question.
The Leiningen folks have now addressed this: https://github.com/technomancy/leiningen/issues/898
If you get version 2.1.0 or later, it has the fix. See the bug for details.
UPDATE: (Aug 2013)
I have a project on github I use for experimentation with lwjgl here: https://github.com/rogerallen/hello_lwjgl
I'm also using LWJGL in my shadertone project here: https://github.com/overtone/shadertone
Because Shadertone is a library, I found I needed to package up the natives myself to get it to install reasonably for projects that depend on shadertone.
If anyone has some pull with the LWJGL folks, it sure would be nice if they just put natives into appropriate subdirectories as lein expects in their clojars releases.
Looks like a problem with your LD_LIBRARY_PATH. Are you including the correct .dll or .so files?
You probably need to add something like :native-dependencies [[lwjgl "2.8.2"]] to your project.clj.
Alternatively, you could try setting the right value from your shell:
export LD_LIBRARY_PATH=/home/username/lwjgl-2.8.2/native/linux/
It's a bit confusing why Display is refusing to import, though other classes in the same jar file import properly
(import '[org.lwjgl.opengl Util WindowsAWTGLCanvasPeerInfo])
I suspect that this jar file is broken, perhaps you could try a different version.
I tried debuggin this by running
cd lib
jar xf lwjgl-2.8.2.jar
cd org/lwjgl/opengl/
and then trying to load various classes i see there.
lein swank also does tab completion which can help in exploring classes without extracting them from the shell.
Ran into this today, solved it a bit differently by adding the native directory to :jvm-opts in project.clj:
(defproject projectname "0.0.1-SNAPSHOT"
:description "my project"
:jvm-opts ["-Djava.library.path=native/linux"]
:dependencies [[org.clojure/clojure "1.4.0"]])
I copied the jar files from the latest lwjgl release into lib and copied the native directory into the project root. Seems to work so far:
user=> (import org.lwjgl.opengl.Display)
org.lwjgl.opengl.Display
But I am only just getting started. Anyway, hope this helps someone else :)

upgrading lein project from clojure 1.2.1 to 1.3.0-beta1

I have a leiningen project that uses clojure 1.2.1. I would like to add a dependency to a package that requires clojure 1.3.0-beta1. So I decided to upgrade my project to the newer version.
To be honest I was not sure what that involved but I did the following..
In my project.clj I changed my dependency from
[org.clojure/clojure "1.2.1] to [org.clojure/clojure "1.3.0"]
I use swank so I changed my swank clojure dependency to [swank-clojure "1.3.2"].
I then ran
lein deps
Lastly I manually edited my /usr/bin/lein file to change the CLOJURE_JAR variable to point to the newer clojure jar.
When I start swank with 'lein swank'. It starts fine and I now get the following warning messages
like so..
Warning: default-javac-options not declared dynamic and thus is not dynamically rebindable, >but its name suggests otherwise. Please either indicate ^:dynamic default-javac-options or >change the name.
Which I think has to do with clojure 1.3.0.
I then fire up Aquamacs and run slime-connect. The REPL starts fine but when call clojure-version
if get "1.2.1".
; SLIME 20100404
user> (clojure-version)
"1.2.1"
Is there something else I need to do?
I think, that you need to add :exclusions list to swank-clojure specification, something like:
:dev-dependencies [[swank-clojure "1.3.2"
:exclusions [org.clojure/clojure]]]
although, I just checked my installation, and clojure 1.3 worked out of box. I think, that you just forgot to call lein clean before lein deps...

How do I use the Apache Commons Codec library from Clojure?

I'm trying to use the Base 64 functions present in the Apache Commons Codec package. I'm using Leiningen, and have this in my project.clj:
:dependencies [[org.clojure/clojure "1.2.0"]
[commons-codec/commons-codec "1.4"]]
Leiningen successfully finds the appropriate .jar. I can't for the life of me figure out which class I actually need to import, though. I have tried all variations of
(ns my-project.core
(:import (org.apache.commons.codec.binary Base64)))
but nothing seems to work. What class name should I be using for this?
I would recommend cutting to the chase and checking where the rubber hits the road. Make sure Leiningen did in fact place the correct jar in the lib directory of your project. Open the jar and look inside and see of the class you are looking for is there. If the path to that class in the jar should match the path of your import statement.
Whoops. It looks like I was just calling the class itself incorrectly. The following worked fine after the :import line above: (.decode (Base64.) s). Thanks for the responses, everyone.