Rewriting Java code to use JavaScript->Java API

[Segi]

I am rewriting and expanding on a snippet of Java code that will check a given URL and verify if the domain is up and if the specific page on the domain is valid (I.E returns a 200 status code vs a 404).

The original Java code:

Code: Select all

try {
     HttpURLConnection.setFollowRedirects(false);
     // note : you may also need
     // HttpURLConnection.setInstanceFollowRedirects(false)
     HttpURLConnection con = (HttpURLConnection) new URL(URLName).openConnection();
     con.setRequestMethod("HEAD");
     return (con.getResponseCode() == HttpURLConnection.HTTP_OK);
 } catch (Exception e) {
      e.printStackTrace();
      return false;
}

This is what I have so far:

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function URLisValid(url) {
     try {
          var url=new java.net.URL(url);
          var socket=new java.net.Socket(url.getHost(),443);

          var httpCon=new java.net.HttpURLConnection(url.openConnection());
          httpCon.setRequestMethod("HEAD");
          alert("Resp code=" + httpCon.getResponseCode());
          return (httpCon.getResponseCode() == java.net.HttpURLConnection.HTTP_OK);
     } catch (e) {
     	  alert("Error 1 " + e);
          return false;
     } finally {
          try {
               socket.close();
          } catch(e) {
               alert("Error 2 " + e);
               return false;
          }
     } 
     
     return true;
}

The line var httpCon=new java.net.HttpURLConnection(url.openConnection()); is throwing the error:

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Error 1 JavaException: javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

This appears to be some kind of SSL certificate issue if I understand the error message but I have no idea how I can resolve it.

[dvanhussel]

Hi,

The most common cause for this problem is that the website you are reading from, uses a SSL cert which uses a root CA cert that is not in your truststore.

You can use the Java command line tool 'keytool' to import the root CA that you need. For example in the default truststore of your JRE:

path/to/jre/lib/security/cacerts

Regards,

David

[Segi]

David,

What would be the syntax for that ? I'm not familiar with how to do that for a public root CA certificate

[dvanhussel]

First, you need the root ca in a plain text .crt file (open a https url on this site in FireFox, open certificate details, select the root cert and click on 'export')

Then, it should be something like:

Code: Select all

keytool -import -trustcacerts -keystore /opt/java/jre/lib/security/cacerts -storepass changeit  -alias mycert -file /tmp/examplecert.crt

'changeit' is the default password for the cacerts truststore
keytool should be in the 'bin' folder of your JRE.

After a successfull import, a restart of Tomcat is needed.

For more info see:

https://www.sslshopper.com/article-most ... mands.html

Regards,

David

[Segi]

David,

Based on what you are telling me, you can only validate if a URL is valid if its a URL that you own. This isn't exactly what I want. I would like to be able to use my function with other sites. Is there any other way to validate a site that uses SSL ? All I care about is if the URL is valid. I don't care about the contents whatsoever.

[Jon]

Segi,

As an alternative, there is an FPL function that will do this for you, but it has to be installed first using Server Admin - see http://www.ebasetech.com/ebase/doc/cust ... c252439253. Then you can call it from Javascript with something like:

var url = "http://www.google.com";
var resp = system.executeCustomFunction("testurlconnection", [url]);
if (resp == "Y")
..

You should only need to add a cert to your keystore if it's unsigned.

Regards
Jon

[Segi]

Jon,

Thanks,

That function does not work with SSL based URLs that use https. I have found that URLS that redirect http to https still work.

I made a change to our server after this problem had already started but I'm not sure if it matters or not. I didn't want to use myserver.com/ebase/FORMNAME so I set the default app to ROOT so I can use the URL myserver.com/MYFORM.eb without referencing any web app.

When I enter the test server parameters now, it reads localhost,80,ROOT under external server.

I can manually connect to the server admin app by entering the URL http://myserver/ebaseAdmin.eb

[Jon]

This works for me with an https URL e.g. https://www.google.com. Are you sure that the URL you are checking is using a signed certificate?

[Segi]

Jon,

When the URL is "http://www.google.com" resp='Y'
When the URL is "https://www.google.com" resp="N"

[Jon]

That's a bit weird because both return a 'Y' for me. I suspect it's throwing some sort of exception that is being swallowed - but I'm guessing. I have no idea why your system is any different from mine.