Working With iOS WKWebView

[zeltas]

I've successfully integrated nomnoml within an iOS app. However, it seems WKWebView operates differently from standard browsers like Firefox and Safari.

Typically, the app creates the script and pushes it to Nomnoml and the diagram is rendered in the WKWebView browser.

Everything works great except as the digram gets larger, the sub texts must be reduced in length or Nominal renders a blank page to screen. The only fix is to reduce the length of the subtexts so the diagram reappears. At some point with a very large diagram, the subtext may have to be reduced to little or nothing. This becomes pointless because we need to see the full data in the diagram.

To help resolve this issue I have come up with this list:

1. How does Nomnoml handle subtexts?
2. What issues can cause Nomnoml to not display because the subtext length is long?
3. How can we avoid triggering these scripting errors? The fix.
4. How can we debug or force Nomnoml to display all/any errors so we can see what's going on and address them?]
   (I might not be able to debug Nomnoml in WebView because it displays a blank screen on errors).

If we can figure out Nomnoml inner workings with subtexts, we may be able to resolve or come up with a fix to address this issue.

[ Heading Title | subtext subtext subtext; subtext subtext subtext ]

This issue can NOT be reproduced in standard web browsers like Safari and Firefox, only in WKWebView. It might be how this mobile browser addresses or approaches security. In other browsers, large subtexts renders fine without issues.

For example: WKWebView doesn't accept Nonnoml use of symbols as filenames. We discovered this error when we kept getting sandbox errors, and opted to combine Nomnoml and supporting files into a single file to avoid sandboxing issues. Only to discover the sandbox security errors were being attributed to Nomnoml's use of symbols as filenames.

Once we corrected the errors in Nomnoml, the sandbox security errors went away.

And as always, thanks for any assistance in this matter.

[skanaar]

Sorry, I can't really help you here.
Getting this to work in a WKWebView is a bit of an advanced use case which is a bit out-of-scope for this project.

But I would love to integrate any bugfixed you make. Please make a PR if you would like to contribute.

[zeltas]

The WKWebView browser did not report these errors - just a blank screen. So I ran the code I used back in safari and found this error in Page Source:

Drilling down further we see:

And going to the location, I came across this:

so on line 1485 of our code in the getPath function, we found this (your line number may differ):

var Ω = path.length - 1; 
var copy = path.map((p) => ({ x: p.x, y: p.y })); 
var tokens = r.assoc.split(/[-_]/); 
copy[A] = add(copy[A], mult(startDir, size * terminatorSize(tokens[0]))); 
copy[Ω] = add(copy[Ω], mult(endDir, size * terminatorSize(last(tokens))));  

We revised it to the following code:

var q = path.length - 1;
var copy = path.map((p) => ({ x: p.x, y: p.y })); 
var tokens = r.assoc.split(/[-_]/); 
copy[A] = add(copy[A], mult(startDir, size * terminatorSize(tokens[0]))); 
copy[q] = add(copy[q], mult(endDir, size * terminatorSize(last(tokens))));

So the only modification made was revising the symbol declaration and changing the symbol Ω to q for the filename reference.

Originally, this created the sandbox error in iOS which I felt was Nomnoml's attempt to access its dependency files (which might not have been allowed under the sandbox rules). Once the files were inline, we knew this was no longer the issue. But we had to run the code back on Mac Safari to find the specific type of errors that WKView had encountered.

Merry X-Mas.

[skanaar]

Good find! I don't even remember that I used an Ω as a variable name.
I'll fix that!

[skanaar]

v1.5.3 released with a fix for this issue
https://www.npmjs.com/package/nomnoml

[42sol-eu]

I've successfully integrated nomnoml within an iOS app. However, it seems WKWebView operates differently from standard browsers like Firefox and Safari.

do you have a way to share? nomnoml on ios would be a-mazing!