atom-latex is not showing the preview PDF

[stefaniecg]

After the last update, my atom-latex package does not show the preview PDF.
The last version it works in is 1.130.1 arm64
Please help,

[savetheclocktower]

Let me pull in an outside expert: @asiloisad, do you think this one might just come down to PDF.js being too old?

(We might be able to fork this package to update the dependencies.)

[asiloisad]

I looked into this and found the root cause. It's not related to PDF.js dependencies, it's an IPv6 URL formatting issue.

C:\Program Files\Pulsar\resources\app.asar\node_modules\@electron\remote\dist\src\renderer\callbacks-registry.js:54 Uncaught (in promise) Error: ERR_INVALID_URL (-300) loading 'http://::1:63870/viewer.html?file=preview.pdf'
    at rejectAndCleanup (node:electron/js2c/browser_init:2:78355)
    at finishListener (node:electron/js2c/browser_init:2:78517)
    at WebContents.failListener (node:electron/js2c/browser_init:2:78803)
    at WebContents.emit (node:events:518:28)
    at WebContents._.loadURL (node:electron/js2c/browser_init:2:79705)
    at BrowserWindow.n.loadURL (node:electron/js2c/browser_init:2:13177)
    at C:\Program Files\Pulsar\resources\app.asar\node_modules\@electron\remote\dist\src\main\server.js:480:71
    at IpcMainImpl.<anonymous> (C:\Program Files\Pulsar\resources\app.asar\node_modules\@electron\remote\dist\src\main\server.js:323:27)
    at IpcMainImpl.emit (node:events:518:28)
    at WebContents.<anonymous> (node:electron/js2c/browser_init:2:83569)
    at WebContents.emit (node:events:518:28)

In newer versions of Electron/Node.js, localhost resolves to the IPv6 loopback address ::1 instead of the IPv4 127.0.0.1. The package's built-in HTTP server binds to localhost, but when constructing the viewer URL, it doesn't account for IPv6 addresses.

In lib/viewer.coffee, the getUrl method builds the URL like this:

{ address, port } = @latex.server.http.address()
@url = """http://#{address}:#{port}/viewer.html?file=preview.pdf"""

When address is ::1, this produces http://::1:63870/viewer.html?file=preview.pdf, which is an invalid URL. Per the URL spec, IPv6 addresses must be enclosed in square brackets: http://[::1]:63870/....

The error in the dev console confirms this:

ERR_INVALID_URL (-300) loading 'http://::1:63870/viewer.html?file=preview.pdf'

The fix is a one-line change in lib/viewer.coffee:

getUrl: ->
    try
      { address, port } = @latex.server.http.address()
      host = if address.includes(':') then "[#{address}]" else address
      @url = """http://#{host}:#{port}/viewer.html?file=preview.pdf"""

After this change the preview works fine again.

[savetheclocktower]

@stefaniecg, sounds like you have two options:

• Make the suggested edit locally in ~/.pulsar/packages/atom-latex/lib/viewer.coffee, then reload your window. Quickest fix, but you may have to do it again in the future if you migrate to another computer.
• Investigate the other toolchain written and maintained by @asiloisad; would probably involve some changes to your workflow, but the upside might be worth it.

Luckily, you don't have to choose between these options; you can pursue both if you like.

[asiloisad]

I'm user of LaTeX too, but I'm using latex-tools and pdf-viewer. I'm the author of these packages and actively maintain them. The latex-tools is likely be smaller than atom-latex, but if you find something useful missing, I can add it probably. The pdf-viewer is newest pdf.js, adapted to works with Pulsar themes and other community packages e.g. scrollmap-pdf-viewer, navigation-panel.