Re^2: Accessing javascript variable from perl

The content calls says:

<html><head></head><body><pre style="word-wrap: break-word; white-spac
+e: pre-wrap;">
//list of the entries in the headings drop box
//the keys give the corresponding elements in the rows
var leg = {
aa: " ... ",
...
};
</pre></body></html>
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The return statement gives an error if not included in a 'function () {}'

Error while executing command: executeScript: An unknown server-side e
+rror occurred while processing the command.: {"errorMessage":"Return 
+statements are only valid inside functions",
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LanX proposal fails also:

my ($val, $type) = $js->eval_in_page('(function() {return JSON.stringi
+fy(leg);})()');
print "val: $val, type: $type\n";
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Gives the error

Error while executing command: executeScript: An unknown server-side e
+rror occurred while processing the command.: {"errorMessage":"Can't f
+ind variable: leg","request":{"headers":{"Accept":"application/json",
+"Connection":"TE, close","Content-Length":"74","Content-Type":"applic
+ation/json; charset=utf-8","Host":"127.0.0.1:8910","TE":"deflate,gzip
+;q=0.3","User-Agent":"libwww-perl/6.15"},"httpVersion":"1.1","method"
+:"POST","post":"{\"args\":[],\"script\":\"return (function() {return 
+JSON.stringify(leg);})()\"}","url":"/execute","urlParsed":{"anchor":"
+","query":"","file":"execute","directory":"/","path":"/execute","rela
+tive":"/execute","port":"","host":"","password":"","user":"","userInf
+o":"","authority":"","protocol":"","source":"/execute","queryKey":{},
+"chunks":["execute"]},"urlOriginal":"/session/95efd1d0-8ea9-11e9-b043
+-85beee600173/execute"}} at C:/strawberry/perl/site/lib/Selenium/Remo
+te/Driver.pm line 389.
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Update:

The content seems strange to me, should the js code not be include in script tag ?

Comment on Re^2: Accessing javascript variable from perl Select or Download Code

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Re^3: Accessing javascript variable from perl by LanX (Saint) on Jun 14, 2019 at 14:51 UTC
The errorMessages are explicitly given! `"Return statements are only valid inside functions"` I explained this already `"Can't find variable: leg"` so my proposal doesnt fail it's your JS Code. Either you can't access the namespace of `leg` or you misspelled it. Though you may want to try `window.leg` or play around inside your browser's JS console (normally type F12 to get there) HINT: `var` denotes a lexical var inside a function°, it only becomes global* if used outside. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice} updates °) mostly like `my` in Perl except for the hoisting effect *) in this case it behaves mostly like `our` in Perl	[reply] [d/l] [select]
Re^4: Accessing javascript variable from perl by frazap (Monk) on Jun 18, 2019 at 07:18 UTC
With the file ~~jello.js~~hello.js `var leg = { aa: "Hello from javascript" } function to_json() { return JSON.stringify(leg); }` [download] And the file perl.pl `use strict; use warnings; use WWW::Mechanize::PhantomJS; my $js = WWW::Mechanize::PhantomJS->new(launch_exe=> 'C:/prog/phantomj +s/bin/phantomjs.exe'); $js->get_local("hello.js"); #$js->update_html('<script src="hello.js" type="text/javascript"></scr +ipt>'); #print $js->content; #my ($val, $type) = $js->eval_in_page('JSON.stringify(window.leg);'); my ($val, $type) = $js->eval_in_page('to_json()'); print "val: $val, type: $type\n";` [download] I can't have any meaningfull result from calling `eval_in_page` either on the `leg` var directly or via the function. Can you show me how to have this working ? Thanks Update without phantomjs `use strict; use warnings; use Log::Log4perl qw(:easy); Log::Log4perl->easy_init($ERROR); use WWW::Mechanize::Chrome; my $js = WWW::Mechanize::Chrome->new(report_js_errors=>1); $js->get_local("hello.js"); #$js->update_html('<script src="hello.js" type="text/javascript"></scr +ipt>'); #print $js->content; #my ($val, $type) = $js->eval_in_page('JSON.stringify(window.leg);'); my ($val, $type) = $js->eval_in_page('to_json()'); print "val: $val, type: $type\n";` [download] This gives undef for `$val` whatever I'm calling: the `to_json()` function or `JSON.stringify` directly.	[reply] [d/l] [select]
Re^5: Accessing javascript variable from perl by LanX (Saint) on Jun 18, 2019 at 08:15 UTC
hello != jello > I can't have any meaningfull result ... Which error message do you get? I don't have phantomjs installed, so please provide a reproducible example. UPDATE I ran your JS code in the browser's console and it works for me: `> var leg = { aa: "Hello from javascript" } function to_json() { return JSON.stringify(leg); } < undefined > JSON.stringify(leg); < "{\"aa\":\"Hello from javascript\"}" > to_json() < "{\"aa\":\"Hello from javascript\"}"` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l]
Re^5: Accessing javascript variable from perl by LanX (Saint) on Jun 18, 2019 at 11:15 UTC
regarding your update: Neither do I have WWW::Mechanize::Chrome installed. My suggestions are to make sure your JS is really executed (add an alert to show) and this before you try eval_in_page (you could play around with sleep or a similar wait mechanism) HTH! Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^6: Accessing javascript variable from perl by frazap (Monk) on Jun 18, 2019 at 12:12 UTC


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Re^2: Accessing javascript variable from perl

updates

UPDATE