This is a file in the Conan cache that is useful to define a set of key-value pairs that will be sent together with the packages uploaded in the conan upload command. This information is sent as custom headers in the PUT request and, if the server has the capability, as matrix params.
custom_header1=Value1 custom_header2=45 build.name=BuildJob
Artifactory users can benefit from this capability to set file properties for the uploaded files.
If the Artifactory version doesn’t support matrix params yet (available since Artifactory 7.3.2) it will use
the properties from the file that are prefixed with
artifact_property_build.name=Build1 artifact_property_build.number=23 artifact_property_build.timestamp=1487676992 artifact_property_custom_multiple_var=one;two;three;four
Take into account that some reverse proxies will block headers that contain a period in their name, for example Nginx, as they consider it to be a security issue (you can bypass this check adding the ignore_invalid_headers to your Nginx configuration).