How to access the admin interface of an EmbeddedSolrServer instance? - java

In my web app I am running an org.apache.solr.client.solrj.embedded.EmbeddedSolrServer
for debugging purposes I would like to access the admin interface.
This is how I instantiate the server:
new EmbeddedSolrServer(new CoreContainer.Initializer().initialize(), "");
Is there a way to open the admin interface of this embedded server like so?
http://localhost:<defaultport>/admin
If so which port would I have to use (what is the default port)?
Else is there a setting that I use to specify the web path for accessing the admin UI?

No, there isn't. At least, not while your application is running.
The embedded solr server reads and writes the index directly on your filesystem in your solr install directory. To access the admin console, shut down your app. In a console navigate to your /example in your solr install directory. Type java -jar start.jar. Then, you can navigate to http://localhost:8983/solr
to access the admin directory.
You can not have your solr server running and be running an application that accesses the same index via EmbeddedSolrServer or you will get a LockObtainFailedException. Solr only allows one reader/writer per index at a time, and that reader/writer obtains a 'lock' in order to access the index. This prevents the index from becoming corrupted from multiple simultaneous reads/writes.
For that reason, I prefer to use the HttpSolrServer instead of the EmbeddedSolrServer, even for a development environment.
See:
http://wiki.apache.org/solr/Solrj#EmbeddedSolrServer

Yes you can, just use reditect tricks
redirect the url you want
http://localhost:/admin
to solr admin url
http://localhost:8983/solr

Related

How to deploy war file to Glassfish?

I've developed a RESTful web service in netbeans and it made a .war file for me. now i want to deploy it to my host using glassfish.
there are lots of tutorials on the net about deploying war file to glass fish(for example) but they all describe how to deploy to local machine(localhost), but as i mentioned i want to deploy to my website host. how to do that?
You should be able to do that using the admin console. This is an old documentation link, but it is still valid:
http://docs.oracle.com/cd/E19798-01/821-1757/ghgjn/index.html
It tells you to go to http://localhost:4848 but you will obviously need to make sure that you can access the admin console remotely (i.e. replacing localhost with your hostname).
If not, you will need to use the command-line asadmin commands change-admin-password (if the admin password hasn't been set - it defaults to nothing) follwed by enable-secure-admin to allow remote access. Remote access to the console is only allowed over https, so these two steps are necessary before you can use it.
You will need SSH access to the server you are using to enable that - but if you already have SSH access then you can always use SCP or FTP to transfer your WAR to the server and then follow the steps in the guide you linked to.

How can I restrict access to the php file on server to Java app only?

I have a Java application that sends user score to the mysql table. When the user is done, Java app accesses the .php file on server and the .php server performs a query on the database (inserting score).
I am concerned about the (in)security of this method. I mean, if someone finds out the direct url to the .php on a server, they can produce a lot of mess in the dabase. Can you advise how I could prevent the .php from executing the query other than accessed by the Java app?
edit: The problem is that Java application is NOT run on the server, it's run on the user computer using Java Web Launcher platform. So it's not an applet...
The problem is conceptual. You should never be sure that users can't find out the real address (security by obscurity). You could use SSL, still this is no means against a good guess.
Since the Java program is run on the client side, a .htaccess restricting access to a certain IP is also not an option.
My suggestion is to create a separate user in mysql, grant this user access only to necessary tables and perform the database queries on behalf of this user directly in Java. This way all data is encrypted (see http://dev.mysql.com/doc/refman/5.5/en/ssl-connections.html) and no URL/access point is exposed. Of course it means your MySQL server must be reachable from outside which poses a risk, too. You should have a good root password!

How to access shared folder on Windows without prompting username/password?

My selenium and java based application needs to frequently read/upload a small-size file from a shared folder (\\some-server-ip\SharedfolderName).
When I run the application on multiple client machine (both server and clients can see their IPs) I am prompted to provide username and password to connect to server IP before the application can access the shared folder.
I have shared folder given full control privileges to everyone, anonymous logon group.
I also added \\some-server-ip\SharedfolderName to local security policy's
Network access: Shares that can be accessed anonymously
But, it is not working.
Interestingly, if I enter the username/password manually first time, it works fine in subsequent runs on that particular client. I cannot manually enter username/passwords on all 700+ of the client machines.
I have been trying to get this to work from past three days, without much success.
Any help/suggestion would be greatly appreciated.
P.S. I have been trying different OS (2008, 2003, Win7) for hosting the shared folder, in a desperate hope to get it to work somehow.
try mapping network drive on your client ?

How to run a Java server on Amazon's EC2?

I want to place a server program written in Java on the cloud. It would accept TCP socket connections from clients (clients are android phones using 3G), do some computations, save stuff to a MySQL database (also on EC2), and send stuff back to the clients over the TCP connections. It may even be necessary to create several instances of the server (i.e. a process group).
Is this easy to do? I think I can make a AMI, but I'm not sure how to upload Java files, compile and run them, and create a MySQL database etc
Any help would be much appreciated.
Take a look at using Amazon Elastic Beanstalk. Beanstalk is Amazon's PaaS offering and it will alleviate a lot of the system administration burden. Here's a quick description from their docs:
AWS Elastic Beanstalk is an even
easier way for you to quickly deploy
and manage applications in the AWS
cloud. You simply upload your
application, and Elastic Beanstalk
automatically handles the deployment
details of capacity provisioning, load
balancing, auto-scaling, and
application health monitoring.
Also, if you're interested in using MySQL then you should look at Amazon RDS. Again, this will alleviate the system administration burden for your database tier. Here's a quick description from their docs:
Amazon Relational Database Service
(Amazon RDS) is a web service that
makes it easy to set up, operate, and
scale a relational database in the
cloud. It provides cost-efficient and
resizable capacity while managing
time-consuming database administration
tasks, freeing you up to focus on your
applications and business.
Is this easy to do? I think I can make
a AMI, ...
I think the answer depends on how comfortable you are with system administration in general. Creating a AMI to run in EC2 is really pretty much the same as creating a physical server or a VM image. You'll need to install an operating system, and then install tools, libraries and programs you need (like mysql, the jdk, ssh, etc).
You can save yourself a little work by using one of Amazon's pre-built AMI's http://aws.amazon.com/amis/. But, ultimately, you'll be responsible for all system administration of the server. If you've never built a server from the ground up, you have a pretty big learning curve ahead of you. It's not insurmountable, but just be warned that the devil is in the details; there's a ton of stuff you'll need to learn ;-)
... but I'm not sure how to upload Java
files, compile and run them, ...
Once the server is setup and running in EC2, compiling them and running java files is just the same as compiling and running on your local. Normally, you probably want to compile and package your java app into a jar or war and then transfer that up to your EC2 server. If you install linux os on your EC2 server, you can use scp or a FTP client to transfer your files over sftp to move the files from your local up to the server. Once the latest files are up on your server, you can ssh to the server and start your app.
... and create a MySQL database etc ...
Installing mysql is going to be specific to the OS you choose to install on your server. For example, you can install mysql easily on Ubuntu with a command like:
sudo aptitude install mysql
Again, there will be more system-admin-type stuff to learn here specific to mysql databases.
So, it's definitely doable. An experienced sys admin could build a AMI instance pretty easily/quickly. If this is your first experience with system administration, I'd suggest finding an old Desktop you have lying around and try installing Ubuntu and all the required libraries and tools you need (mysql, jdk, ssh, etc..). Get your java program working on the old desktop and then it should be pretty easy to create an AMI from that. Then you can run your custom AMI on EC2 and will be set up.
If you don't have a spare desktop lying around, you can use one of the Virtual Machine products like VMWare Player or Sun's VirtualBox and build a server instance on one of those.
If you want to avoid the hassle of managing the entire install of the Operating system, you might want to look at services like slicehost and/or linode instead of EC2. They give you ssh access to a pre-installed server. And it's as easy as clicking a button to install programs like mysql, etc.
Hope this answer is relevant and helpful, good luck.
- Dave
If you can use Tomcat as your server - you might want to try Amazon Web Services Elastic Beanstalk It will greatly simplify your task by providing an easy instance of Tomcat to deploy.
EDIT: AWS has a full section on how to develop using Java here: http://aws.amazon.com/java/
How comfortable are you with remote administering a server and solving problems most people have never heard of? That's what you're talking about.
You'll create your EC2 instance, log into it and configure it like you would any other server you're working with. You can download JDKs to it, dbs etc. You might consider using a tool like Chef to help you. You'll use ftp and scp to copy files to the server.
You're probably going to want your Java server on one box and have it talk to a separate db server since you say you may want multiple servers.
Once the server is working the way you like it you can create an image of it to use to launch multiple instances, then configure a load balancer to point at your servers.
If you can create a MySql db on your local box you can create it in the cloud. If not?....
Running Applications needs app. s/w to run them.
Apps such as Cyber Duck helps to upload files via SFTP.
I am successful in doing the same problem addressed.. Trust me, YOU CAN DO IT. All u need is interfaces for server services such as MySQL (use WorkBench to connect using key pair), terminal access (using PUTTY/SSH via MAC) and well you are good to go
I think to get started is to use a a whole unit packed into one archive.
Think of it as you have your Java files compiled, a embedded http server say tomcat. Now all of this packed in a jar ready to be deployed on Amazon's EC2. Use this link for more on embedded servers and relevant code.
As far as database is concerned, you can use Amazon's RDS. You can configure mysql on RDS and obtain a link to it for connection. Amazon RDS would help you to get started with database.
Now that you have everything ready to start and work with application. Now is the time to deploy on Amazon AMI
Perform Following steps to deploy you app on Amazon EC2:
Create a server instance on Amazon EC2 refer EC2 getting started.
Receive Private key file i.e. .pem(receive from Step 1), this file would help you to login to your server instance and perform SFTP.
Use Putty or similar SSH client to login to your EC2 server instance created on Step-1 using .pem file and server's public DNS, refer Accessing Instance for SSH login.
Transfer the archived files packed into jar to server using SFTP client, WinnSCP being one such client, refer SFTP for more on it.
Run application. Note in case of jar file you can simply fire java -jar TomcatApp.jar.
If everything is configured properly you would be to access the app using EC2 instance's public DNS or public IP, which would be of the form:
http://<public_dns_address>:<port number>/servlet
Hope it helps you to get started and provide you an overall view.

Servlet throws file not found excp when accessing network drive

I've a production env and test env. Production has win2k3+tomcat 6.0+ and network drive mapped to a drive letter for easy access (z:\app instead of \symba\files\app). My test env has windows xp (all the software is same including the source code for servlet) and test also has the same drive letter mapping to the network drive.
Tomcat is running with the same user id in both the systems and am able to access the file via windows explorer in the test m/c and production m/c.
Now the servlet in the windows xp m/c (test m/c) throws a file not found exception if try to access an existing file (reachable via windows explorer). The servlet in production is same as in test env and production servlet happily gives the file when i request it and does not throw any error what so ever.
I've see some posts that using drive letter is not a good idea and should use UNC paths instead and i've not tried this yet. I want to know the reason why test servlet fails to get file whereas production servlet works fine.
Thank you very much for your time and help
Bo
Are you running the application server as a service? Drive letter assignments are reliable only if you use interactive programs not services.
A couple of years ago, I tried to resolve a quite identical problem but, at last, I gave up and I used JCIFS to access the files.
If you run Tomcat with a security manager, the web app code is according to the default configuration only allowed file access to its deployment directory. If you want to change the application policies, you can do that in conf/catalina.policy or you can disable the security manager, if you want your web app code to gain all privileges.
You might want to consider running the Tomcat service as the user who has access to the mapped drive.
As pointed out by andcoz, the mappings will not apply for the SYSTEM user in Windows that I presume is being utilized for running Tomcat. You could change the service configuration to run as the user owning the drive mapping and verify if the failure continues to occur.
Related:
FileNotFoundException thrown when the file does exists.

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