Building post lists of multiple versions

[omalaspinas]

Hello,

sorry if it is a silly question. I am currently producing multiple versions of posts (html and pdf) and want to list them on a page. While have only the html version works just fine, I can't find a way to dynamically also show both versions. I usually end up with an error message like

  [ERROR] Hakyll.Core.Compiler.Require.load: test.markdown (pdf) (snapshot _final) was found in the cache, but does not have the right type: expected [Char] but got TmpFile

Any idea/advice on how to have both versions in the list?

Thanks in advance for your help.

[Minoru]

Hi! A fellow user here. Do you have a minimal example of this somewhere? I don't have an answer for you offhand, but I'd like to take a look at the code and see if I can help somehow.

[omalaspinas]

Hello,

thank you very much for your answer. Basically what I'm doing is that I first generate two "versions" of my markdown files: one in html and the other in pdf (this is copy pasted from https://github.com/jaspervdj/jaspervdj basically):

    -- posts
    match "posts/*.markdown" $ do
        route $ setExtension "html"
        compile $ pandocCompiler
            >>= loadAndApplyTemplate "templates/class.html" postCtx
            >>= relativizeUrls

    -- posts in PDF
     match "posts/*.markdown" $ version "pdf" $ do
         route   $ setExtension "pdf"
         compile $ do getResourceBody
             >>= readPandoc
             >>= writeXeTex
             >>= loadAndApplyTemplate "templates/default.latex" defaultContext
             >>= xelatex

    where
      writeXeTex :: Item Pandoc.Pandoc -> Compiler (Item String)
      writeXeTex = traverse $ \pandoc ->
          case Pandoc.runPure (Pandoc.writeLaTeX Pandoc.def pandoc) of
              Left err -> fail $ show err
              Right x  -> return (T.unpack x)

xelatex :: Item String -> Compiler (Item TmpFile)
xelatex item = do
    TmpFile texPath <- newTmpFile "xelatex.tex"
    let tmpDir  = takeDirectory texPath
        pdfPath = replaceExtension texPath "pdf"

    unsafeCompiler $ do
        writeFile texPath $ itemBody item
        _ <- Process.system $ unwords ["xelatex", "-halt-on-error",
            "-output-directory", tmpDir, texPath, ">/dev/null", "2>&1"]
        return ()

    makeItem $ TmpFile pdfPath

This generates .html and .pdf files as I want (which is a good first step).

Then I would like to do something like

    -- post list
    create ["posts.html"] $ do
        route idRoute
        compile $ do
            posts <- recentFirst =<< loadAll ("posts/*.markdown" .&&. hasVersion "pdf")
            makeItem ""
                >>= loadAndApplyTemplate "templates/archive.html" (pageCtx posts "MyPage")
                >>= relativizeUrls

Unfortunately it miserably fails with the error message printed above (that I reproduce below for completeness....). It works fine without the pdf part though.

  [ERROR] Hakyll.Core.Compiler.Require.load: test.markdown (pdf) (snapshot _final) was found in the cache, but does not have the right type: expected [Char] but got TmpFile

The rest of the code is basically like in any hakyll example (copying static files, ...).

[Minoru]

Hmm, I don't see anything wrong with your code. I tried to reproduce the problem with my own blog by replacing hasNoVersion with hasVersion "gzipped" here ("gzipped" versions are produced here using a compiler very similar to yours), but no luck: for me, it just works.

Perhaps your cache is broken by some previous experiments? Try running yoursite clean (stack run -- clean, Cabal probably has a command for that too, haven't used it in a while) and retrying then.

If that doesn't help, can you please post the whole code somewhere so I can clone it and play around? Copy-pasting things from here and there is a bit slow, and I might end up with a setup that's slightly — but crucially — different from yours.

[omalaspinas]

Thanks! I'll try to put a minimal example somewhere. For the moment it's in a huge file with some useless stuff that only add noise. I'll post it during the week I guess.