Setting cors:true in config.json throws exception

[barocsi]

\node_modules\cors\lib\index.js:188
o.origin = defaults.origin;
^
TypeError: Cannot assign to read only property 'origin' of true
at middlewareWrapper (\node_modules\cors\lib\index.js:188:16)
at setupCors (\node_modules\loopback-explorer\lib\swagger.js:145:18)
[..]

"loopback-boot": "^2.6.5",
"loopback-component-passport": "^1.5.0",
"loopback-connector-mongodb": "1.13.0",
"loopback-datasource-juggler": "^2.41.1",

[loay]

so what led to that error? can you provide the steps in order to reproduce the error?
Any repo to be used as well to reproduce the error? thanks.

[barocsi]

Simply node . started the app and it threw error right away. Only this parameter was changed in the config file. Here is the full stack trace
TypeError: Cannot assign to read only property 'origin' of true
at middlewareWrapper (\test\node_modules\cors\lib\index.js:188:16)
at setupCors (\test\node_modules\loopback-explorer\lib\swagger.js:145:18)
at Swagger (\test\node_modules\loopback-explorer\lib\swagger.js:55:3)
at explorer (\test\node_modules\loopback-explorer\index.js:31:3)
at Object.mountLoopBackExplorer as func
at \test\node_modules\loopback-boot\lib\executor.js:287:9
at iterate (\test\node_modules\loopback-boot\node_modules\async\lib\async.js:146:13)
at \test\node_modules\loopback-boot\node_modules\async\lib\async.js:157:25
at \test\node_modules\loopback-boot\lib\executor.js:289:7
at iterate (\test\node_modules\loopback-boot\node_modules\async\lib\async.js:146:13)

[barocsi]

Additionally for which I am confused in the middleware.json cors is enabled
"cors": {
"params": {
"origin": true,
"credentials": true,
"maxAge": 86400
}

[loay]

i used a sample project and I could reproduce the same error when I do node .

for lines 188 and 191
if you use

o.origin == defaults.origin;

instead of

o.origin = defaults.origin;

and in line 194, if you use

o.preflightContinue == defaults.preflightContinue;

instead of

o.preflightContinue = defaults.preflightContinue;

That should fix the issue in your project and run the node server fine. If that doesn't work, can you share your project repo? Thanks.

[loay]

@barocsi Still having an issue with that?
Thanks

[loay]

Please let me know if the problem is still persisting .. we will re-open the ticket.
closes #1810

[kartsims]

I am having this issue as well and editing the package directly doesn't feel like a permanent solution... What do you need to help debugging ?

[moklick]

I am having the same issue. I can't set cors: true in the config.json

.../strongloop-app/node_modules/cors/lib/index.js:188
      o.origin = defaults.origin;
               ^

TypeError: Cannot assign to read only property 'origin' of true

[loay]

@kartsims @moklick

• but did the solution in this comment: Setting cors:true in config.json throws exception #1810 (comment)
  work for you guys as a temp solution? It did work for me.
• also, can you please share a repo of your code, so I can reproduce. I will try to push for a permanent solution after I look at your cases.