Cannot copy file to Docker container via Spotify Docker Client

Question

I want to copy file to the not running container via Docker Client by Spotify -

File is created like -

File.createTempFile("olb-", "-temp").deleteOnExit().writeText("some text")

When I try:

client.copyToContainer(inputFileProvider.createFile(task.dataToInsert).toPath(), containerId, "/app/asd.json")

I get:

Either container 1adbf9c1ee511272bec78a46be08bf9299c317b11cdb176eed986640ac86a38c or path /app/my_json.json not found.

Well, ok - I create this file while building image with RUN touch /app/my_json.json Next run:

client.copyToContainer(inputFileProvider.createFile(task.dataToInsert).toPath(), containerId, "/app/my_json.json")

Resulted in

{"message":"extraction point is not a directory"}

Ok... I tried directory

copyToContainer(inputFileProvider.createFile(task.dataToInsert).toPath(), containerId, "/app/")

Result:

{"message":"Error processing tar file(exit status 1): cannot overwrite directory \"/\" with non-directory \"/\""}

Same for "/app"

Any ideas how to copy file into docker container via Java client?

Answer 1

It turned out that I must create whole new folder, then single file in it and copy that folder.

val dir = Files.createTempDirectory("tem-folder-")
Files.createFile(dir.resolve("filename")).toFile().writeText("data to write")

val toBeCopied = dir.toFile()

cliend.copyToContainer(toBeCopied.toPath(), "containerId", "targetPath")