Why is microservice able to load 'txt' files from subdirectory but not ".mat" files?

consider this function loadFile.m:

function w = loadFile()

readlines("subdirectory/txtfile.txt")

load('subdirectory\someMatFile.mat')

w = 1;

end

Which I compiled using:

compiler.build.productionServerArchive

With options set to Include both files in subdirectory as 'Additional Files'. Then I compiled the function to a microservice using compiler.package.microserviceDockerImage.

The issue is - When I start the microservice as a docker container, the function is only able to read from the .txt file in the subdirectory, and not load the '.mat'. This Issue occurs only when loading mat file from subdirectory. if it is located in the same directory as function when compiling, loading is available when running as container.

I modified the DockerFile and rebuilt the image to make the script run as root, so I am confident this isn't a permissions issue.

The error message recieved in the http response:

"error":{"id":"MATLAB:load:couldNotReadFile","message":"Unable to find file or directory 'subdirectory\\someMatFile.mat'}

[Dyuman Joshi]

Best to use fullfile instead of manually providing a path.

Answer 1

[Fangjun Jiang]

Notice the two backslashes "\\" in the error message about the file?

"error":{"id":"MATLAB:load:couldNotReadFile","message":"Unable to find file or directory 'subdirectory\\someMatFile.mat'}

Does it make a difference between slash "/" and back slash "\"? Try to use

fullfile('subdirectory','someMatFile.mat')

ans = 'subdirectory/someMatFile.mat'

filesep

ans = '/'

[Aran Ofer]

Thanks, Error turned out to be a combination of path specification and partial inclusion of Additional Files at compilation.