Can't use aws-amplify or aws-sdk with npm-deps

Question

If I put {{aws-amplify}} in {{:npm-deps}} it seems to require {{aws-sdk}}, but when I put {{aws-sdk}} in there, it outputs this error:

`
Compiling build :dev to "resources/public/js/main.js" from ["src"]...
events.js:182

  throw er; // Unhandled 'error' event
  ^

Error: module not found: "fs" from file /home/quang/dev/org-re-frame/node_modules/aws-amplify/node_modules/aws-sdk/lib/util.js

at onresolve (/home/quang/dev/org-re-frame/node_modules/@cljs-oss/module-deps/index.js:181:30)
at onResolve (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/Resolver.js:70:11)
at innerCallback (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/Resolver.js:143:22)
at callbackWrapper (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/createInnerCallback.js:10:21)
at next (/home/quang/dev/org-re-frame/node_modules/tapable/lib/Tapable.js:249:35)
at innerCallback (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/Resolver.js:143:22)
at callbackWrapper (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/createInnerCallback.js:10:21)
at next (/home/quang/dev/org-re-frame/node_modules/tapable/lib/Tapable.js:249:35)
at resolver.doResolve.createInnerCallback (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/DescriptionFilePlugin.js:41:24)
at callbackWrapper (/home/quang/dev/org-re-frame/node_modules/enhanced-resolve/lib/createInnerCallback.js:10:21)

`

Answer 1

_Comment made by: jffry_

I've also run into the same issue.  Here's a simple repro:

{code:title=deps.edn|borderStyle=solid}
{:deps {org.clojure/clojurescript {:mvn/version "1.10.238"}}}


{code:title=src/foo.cljs|borderStyle=solid}
(ns foo (:require ["aws-sdk" :as sdk]))
(defn -main [] (println "hello world"))


then run:


$ clj -m cljs.main -co '{:install-deps true, :npm-deps {:aws-sdk "2.229.1"}}' -m foo
...
Error: module not found: "fs" from file /Users/jeff/repro/node_modules/aws-sdk/lib/util.js
    at onresolve (/Users/jeff/repro/node_modules/@cljs-oss/module-deps/index.js:181:30)
    at onResolve (/Users/jeff/repro/node_modules/enhanced-resolve/lib/Resolver.js:70:11)
    at innerCallback (/Users/jeff/repro/node_modules/enhanced-resolve/lib/Resolver.js:143:22)
    at callbackWrapper (/Users/jeff/repro/node_modules/enhanced-resolve/lib/createInnerCallback.js:10:21)
    ...

Answer 2

_Comment made by: mfikes_

The big picture is not completely clear to me for this one, but it appears that the NPM version of the library is not intended to be used directly from the browser runtime, and instead you need to build it so that it is packaged for the browser.

The root problem is that the code is attempting to use Node's {{fs}} code, but from the browser.

You can see that the code can be compiled and executed if you target Node: If you modify Jeffrey's minimal repro to add


(set! *main-cli-fn* -main)


to the bottom of {{src/foo.cljs}} then things will compile and execute in Node:


$ clj -m cljs.main -co '{:install-deps true, :npm-deps {:aws-sdk "2.229.1"}}' -O simple -o main.js -t node -c foo
WARNING: foo is a single segment namespace at line 1 /private/tmp/aws/src/foo.cljs
$ node main.js
hello world


For the browser case, if you look at the code in {{node_modules/aws-sdk/lib/util.js}} you can see that it has conditional branches for browser use, but I suspect that this is intended to be used as described here https://github.com/aws/aws-sdk-js#in-the-browser but if you really want to use the code directly from its NPM dependency, you have to use that NPM dependency to build the JavaScript intended to be used in the browser as detailed here: https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/building-sdk-for-browsers.html

If this can be confirmed, then this issue can be resolved as a non-issue, and it is just a matter of correct use of the library.

Answer 3

Comment made by: djwhitt

I can confirm that it works in the browser with the AWS recommended browser build process. I was hoping it would also work as a node dep, but I think you're probably right that it's just not intended to be used that way.

Answer 4

Comment made by: dehli

So adding aws-sdk the recommended way does work, however there are many AWS packages that pull in aws-sdk as a dependency. One example is https://github.com/awslabs/aws-mobile-appsync-sdk-js/tree/master/packages/aws-appsync. This means that these packages won't run in ClojureScript because they throw the same error as above. I have confirmed that in a regular JavaScript project, aws-sdk is added correctly (an example is here: https://github.com/aws-samples/aws-mobile-appsync-events-starter-react/).

Like Mike said, it looks to be coming from this line in the code: https://github.com/aws/aws-sdk-js/blob/ebe83921863f1eb020b6a07ef471f2017cd58550/lib/util.js#L39. process.browser is what's indicating to aws-sdk whether or not it's a browser environment.

My guess would be if we set process.browser to true for when building to non-node environments it would solve this problem (https://nolanlawson.com/2017/01/09/how-to-write-a-javascript-package-for-both-node-and-the-browser/)

Answer 5

Reference: https://clojure.atlassian.net/browse/CLJS-2738 (reported by alex+import)