78436 - PAC: PAC files need to be displayed (not loaded)

Status: NEW

(Firefox :: File Handling, enhancement, P5)

Description

[benc]

Mac, commercial 2001-04-30-08-mtrunk
STEPS:
1- Type the URL of a PAC file into a URL field and hit return

OBSERVED BEHAVIOR:

Netscape 6 tries to download this file:

"Downloading

This file has mime type application-x-ns-proxy-autoconfig and cannot be viewed
in Netscape 6. You can open it with another application, or save it to disk.

[]Open Using
[]Save to disk"

EXPECTED BEHAVIOR:
Communicator 4 would refuse to load and execute PAC files via "normal surfing
methods (typing URL, links, etc).

"Warning:

Server sent an unregistered proxy automatic configuration file to Netscape:
     http://proxy.packetgram.com:443//
Configuration file will be ignored.

POSSIBLE SOLUTIONS:

1- emulate Communicator 4 fully

We need a similar error for mozilla.

2- use a newer, smarter behavior

Treat surfed pac files as text and display them on the screen. Why? When I was a
proxy administrator, I hated working with a configuration file that I could not
easily see. Knowing that the browser can load and display the file is a win for
admins (ease of configuration) and users (they can see where their requests are
going).

NOTES:
The download dialog also was behaving weird in several ways. I used Mac, but
will update for Win32+Linux later:

1- Open does not display the file, but saves it to disk as a text file (openable
in Simpletext)
2- Save suggests a filename, but already creates the file on disk, so you cannot
save to the suggested name. If you change the name so you can save, you get a
corrupted file that has a blank file icon but appears to ResEdit as a folder?!

Comment 1

[benc]

qa to me. 

I don't think this should be futured, so I'm nominating this nscatfood.

Comment 2

[neeti]

-->PAC bugs to Jussi

Comment 3

[Jussi-Pekka Mantere]

Serge, can you take a look at these PAC issues? Thanks - Jussi-Pekka

Comment 4

[Asa Dotzler [:asa]]

Bugs targeted at mozilla1.0 without the mozilla1.0 keyword moved to mozilla1.0.1 
(you can query for this string to delete spam or retrieve the list of bugs I've 
moved)

Comment 5

[serge (gone)]

to default owner

Comment 6

[benc]

qa to me - (pac is back).
+nsbeta1, 4xp - this is a design aspect where I don't fully understand if
downloading is a security issue. Comm 4 had a behavior that we definitely don't
have.

Comment 7

[benc]

-> file handling, now that I think about it.

Comment 8

[Samir Gehani]

Nav triage team: nsbeta1-

Comment 9

[Christian :Biesinger (don't email me, ping me on IRC)]

I think that bug 57342 would basically fix this bug, if I understood it correctly.

Comment 10

[Vedran Miletic]

retargeting

Comment 11

[benc]

I think law is gone.

Comment 12

[timeless]

.

Comment 13

[Boris Zbarsky [:bzbarsky]]

I'm not going to hack layout and parser to know about this random made-up MIME
type.  IMO this should be wontfix and the server should use the JS type for what
is after all a JS file.  Note that we don't try to "load" the PAC file when
loading this way -- we simply don't know what to do with it.

Comment 14

[Christian :Biesinger (don't email me, ping me on IRC)]

bz: maybe a non-hacky solution would be a streamconverter that converts PAC
files to HTML and shows a message as in comment 0 at top and the file in <pre> below

Comment 15

[Boris Zbarsky [:bzbarsky]]

Yeah, that would work.

In fact, could we just write a stream converter to convert arbitrary data to
text/plain?  Then we could stop special-casing all sorts of MIME types in layout
and parser in favor of registering this stream converter with various
contractids, maybe...

Comment 16

[Christian :Biesinger (don't email me, ping me on IRC)]

that would be for things like text/javascript? sounds good to me

Comment 17

[Boris Zbarsky [:bzbarsky]]

Yeah, text/javascript, text/css, application/x-javascript, etc.

Comment 18

[Dan Mellem]

WFM on 1.7a (2004010708); it won't execute it but instead asks what to do with
the file. When I go to our PAC server, I get the normal download dialog:

===========
The file "" is of type application/x-ns-proxy-autoconfig, and Mozilla does not
know how to handle this file type. This file is located at:

http://pac.pusd.org

What should Mozilla do with this file?
.
.
.
===========

I've mapped .PAC to a text editor so opening it in the default application
works. This is also resolved by creating a MIME type in Helper Applications that
always opens it in a text editor (e.g., Notepad).

Comment 19

[benc]

I thought about this, but couldn't get it to work on my Mac. It turns out I had
done the config wrong. It seems to work well, should look at editing the file
handling defaults?

Also, how would you do this for linux?

Comment 20

[benc]

Hmm, after getting this to work on my Mac, I looked at mimeTypes.rdf:

  <RDF:Description
about="urn:mimetype:externalApplication:application/x-ns-proxy-autoconfig"
                   NC:path="/Applications/TextEdit.app"
                   NC:prettyName="TextEdit.app" />

  <RDF:Description about="urn:mimetype:application/x-ns-proxy-autoconfig"
                   NC:description="PAC file"
                   NC:fileExtensions="pac"
                   NC:value="application/x-ns-proxy-autoconfig"
                   NC:editable="true">
    <NC:handlerProp
resource="urn:mimetype:handler:application/x-ns-proxy-autoconfig"/>
  </RDF:Description>


  <RDF:Description about="urn:mimetype:handler:application/x-ns-proxy-autoconfig"
                   NC:alwaysAsk="false"
                   NC:saveToDisk="false"
                   NC:useSystemDefault="false"
                   NC:handleInternal="false">
    <NC:externalApplication
resource="urn:mimetype:externalApplication:application/x-ns-proxy-autoconfig"/>
  </RDF:Description>

My RDF experience is a bit limited, does anyone else want to help me w/ a patch?

Comment 21

[BugBot [:suhaib / :marco/ :calixte]]

In the process of migrating remaining bugs to the new severity system, the severity for this bug cannot be automatically determined. Please retriage this bug using the new severity system.

Comment 22

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:Gijs, could you have a look please?

For more information, please visit BugBot documentation.

Comment 23

[:Gijs (he/him)]

Valentin, do you know if PAC files are still in common use and/or if it would make sense to treat these as text/plain so they showed up inline by default? AIUI this is much simpler to fix than bug 57342 - to fix that bug would require UI work and thinking about what the UX should be in the current world (where the "what do you want to do with this file" dialog isn't the default anyway). But here, I think we could "just" add a converter registration that maps application/x-ns-proxy-autoconfig to text/html using the text-to-html converter, I think? cf. https://searchfox.org/mozilla-central/search?q=streamconv%3B1%3Ffrom&path=&case=false&regexp=false

Comment 24

[Valentin Gosu [:valentin] (he/him)]

PAC files are still very much in use. I'm not sure just how critical it is to be able to display them in the browser though, but looking through the PAC code I don't think treating them as text/plain would cause any issues.

But here, I think we could "just" add a converter registration that maps application/x-ns-proxy-autoconfig to text/html using the text-to-html converter, I think? cf. https://searchfox.org/mozilla-central/search?q=streamconv%3B1%3Ffrom&path=&case=false&regexp=false

Yes, I think that might work. Or otherwise just add a content handler for this content type here? The opposite of what we're doing in bug 1824325 for application/http-index-format.

Comment 25

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:Gijs, could you have a look please?

For more information, please visit BugBot documentation.

Comment 26

[erosman [:erosman]]

PAC files are similar to JavaScript files.
Since Firefox displays JavaScript as plain text, there is no complication in displaying .pac similarly.