Document Image response in Spring REST Docs

Question

I have a REST endpoint that generates random images. I'm using Spring REST Docs, but the Response is all garbled in the http-response.adoc file. Is there an easy way for Mock MVC and REST Docs to store the file somewhere so my .adoc files can reference it?

Answer 1

Not the perfect but working solution:

class ImageSnippet implements Snippet {

    private final String filePath;

    public ImageSnippet(String filePath) {
        this.filePath = filePath;
    }

    @Override
    public void document(Operation operation) throws IOException {
        byte[] picture = operation.getResponse().getContent();

        Path path = Paths.get(filePath);
        Files.deleteIfExists(path);
        Files.createDirectories(path.getParent());
        Files.createFile(path);

        try (FileOutputStream fos = new FileOutputStream(path.toFile())) {
            fos.write(picture);
        }
    }
}

And usage in MockMvc test (image folder path is important):

    mockMvc.perform(get("/my-profile/barcode")
                      .accept(MediaType.IMAGE_PNG))
            .andExpect(status().isOk())
            .andDo(document("my-profile/barcode",
                      new ImageSnippet("build/asciidoc/html5/images/barcode.png")));

In .adoc template:

 image::barcode.png[]

And here is my build.gradle Asciidoctor configuration (imagesdir is important):

asciidoctor {
    dependsOn test
    backends = ['html5']
    options doctype: 'book'

    attributes = [
            'source-highlighter': 'highlightjs',
            'imagesdir'         : './images',
            'toc'               : 'left',
            'toclevels'         : 3,
            'numbered'          : '',
            'icons'             : 'font',
            'setanchors'        : '',
            'idprefix'          : '',
            'idseparator'       : '-',
            'docinfo1'          : '',
            'safe-mode-unsafe'  : '',
            'allow-uri-read'    : '',
            'snippets'          : snippetsDir,
            linkattrs           : true,
            encoding            : 'utf-8'
    ]

    inputs.dir snippetsDir
    outputDir 'build/asciidoc'
    sourceDir 'src/docs/asciidoc'
    sources {
        include 'index.adoc'
    }
}