HTTP 400 - Unable to parse remote repository npm metadata - artifactory

Question

We have 2 remote NPM registries inside of a virtual repository. One of them is the NPM Registry, the other one is from a software provider. When I add the second repository to the virtual repository, I am getting HTTP 400 messages at random.
For example: if I want to install a package from the npm-registry, I see through the logs that Artifactory is trying to get the package from the other repository (which does not have the package) and tries to parse the response as json. The response from the other repository gives back a html file though which results in the following error message:
2017-02-23 09:39:05,424 [http-nio-8080-exec-7112] [ERROR]
(o.a.a.n.r.NpmRemoteRepoHandler:362) - Error while parsing the response of a remote npm
JSON query on 'https://repository.domain.com/api/npm/public/file-loader':
Unexpected character ('<' (code 60)): expected a valid value (number, String, array, object,
'true', 'false' or 'null')
at [Source:org.artifactory.storage.db.binstore.service.UsageTrackingBinaryProvider$ReaderTrackingStream#7360bc6c; line: 1, column: 2]
As you can see, Artifactory is trying to get the package from the other repository. The JSON response of our artifactory, when I try to get the package manually is :
{
"errors" : [ {
"status" : 400,
"message" : "Unable to parse remote repository npm metadata."
} ]
}
Any help would be greatly appreciated, since this makes the NPM Registry completely useless as some requests are returning this HTTP 400 error.
fyi: We are using Artifactory Pro 4.5.1

Answer 1

There are 2 things you should do to avoid this behavior
Configure the virtual repository resolution order so the NPM registry is approached before the software provider registry. The resolution order is controlled by the order they are presented in the Selected Repositories list.
Use include/exclude patterns to control which packages are resolved from the software provider registry. Assuming there is a way to identify the packages which should be resolved from software provider you can define patterns which will limit this registry only for the resolution of certain packages.
Another thing to check is whether the software provider remote repository configured properly. Normally it should not return an HTML response for an API call.