Introspect in-memory H2 Database - h2

My Play app uses H2 in-memory database when it runs in dev or test mode. I want to access this database when the app runs in dev mode. So I have the following options
1) Run the database in Embedded/Mixed mode. And make the play framework expose the database to other processes.
2) Run in H2 database in server mode (least preferred). But in this the framework should start the database server deamon process (not manually).
My current application.conf file looks like this.
db.default.driver=org.h2.Driver
db.default.url="jdbc:h2:mem:dev;MODE=MYSQL;DB_CLOSE_DELAY=-1;"
db.default.jndiName=dev

From your terminal use activator cmd to run Play's console, within it run h2-browser cmd to open console in the browser and finally run your app (withinh the same Play console) with ie run cmd.
Make sure that you are using the same credentials (especially JDBC URL) in both places.
AFAIK it uses embedded mode (therefore it's required to start both within one process)
(origin)

Related

How to Secure SQLite database?

We have a windows application which is written by electron and SQLite as database, the problem is we want our application to secure the database file after its first authentication with database, and only have the application itself can modify the file, while preventing the windows standard user from modifying or deleting the file manually. What are the options here?
You can use third-party applications like https://robotronic.de/runasspcen.html
Run application as another user or start program as administrator from a limited account like the command runas, but without to enter login information on each start.

Create an H2 Database from the console

I would like to run H2 on my local host (Windows), and create a new database.
To do so, I have dowloaded the zip file from http://www.h2database.com/html/main.html, unzipped it, then run the bin/h2.bat script. I have not used the windows installer, as the machine I will be running later on does not grant me installation privileges.
The console was successfully opened on the 8082 port, but I could not create any database, failing with Database "C:/Users/PC/test" not found [90013-198] 90013/90013. I have tried many variations, to no avail.
The documentation states that a database should be created automatically if it does not exist, but indicates it cannot be done so from the H2 console (http://www.h2database.com/html/tutorial.html#creating_new_databases).
However, the documentation does not provide an alternate way to create a database, either by running the jar with additional parameters, or by another utility.
I feel pretty dazed right now. How do I properly create a new database in H2? I would like a normal database, persisted on disk, not an in-memory one.
I would suggest that this does not work in version 198
You could download an older version (I used 196) to create the databse and then switch back to 198 to open the database.
I have managed to run it by using the following command line:
java -cp h2-1.4.198.jar org.h2.tools.Server -tcp -pg -web
I must have missed something in the documentation, sorry about this.

RethinkDB does not create help and help_internal databases

I am trying to use the Horizon framework by the RethinkDB team but I am facing startup issues with Rethink. I try to start up the server with the command
rethinkdb --http-port 8082
all works fine but when I run my app.js where horizon is embedded, I obtain the error.
error: Connection to RethinkDB terminated: Error: The database help_internal does not exist.Run hz set-schema to initialize the database, then start the Horizon server.
I ran the command above and it creates a rethinkdb_data folder and whenever I restart the server, it gives me the same error.
You need to tell hz set-schema how to connect to the RethinkDb server you're running, otherwise it will create its own in your current working directory. You can pass it the same connection options you pass to hz serve.
I also got this error. It can be confusing because in dev mode of horizon it usually creates these databases for you.
In prod, however, you must create the databases yourself. To do this it is as simple as logging into RethinkDB's admin interface, click on the "Tables" navigation item then clicking the "+ Add Database" button. Create two databases called 'help' and 'help_internal' assuming that your horizon project_name name is 'help'.
Note that in addition to creating the databases I've described you may also need to create tables in these databases. This is where you should use get-schema on your dev server (to dump the current schema to disk) and set-schema on your prod server (to create the tables needed to support the schema).
For some npm tasks that accomplish the getting and setting of schema you can see here.

Using Session with Schedule

I'm using Laravel 5.2.29 and I've set up some scheduled commands.
One of them uses some methods used in my app through normal use (i.e., via a browser) and so the session is accessible.
However, when I try and run the command manually using artisan schedule:run, I get the following exception:
Session store not set on request.
The Session isn't being set (I suppose in the same vein as if a route were accessed without the web middleware), so is there a way to manually boot up the Session? I'd rather not rewrite my methods to not use it.
You don't have access to the session in CLI. Session is strictly connected with the web browser (client side) which doesn't make sense in command line.
If You need a local storage (for server side) You can try with cache driver.

How does one run Spring XD in distributed mode?

I'm looking to start Spring XD in distributed mode (more specifically deploying it with BOSH). How does the admin component communicate to the module container?
If it's via TCP/HTTP, surely I'll have to tell the admin component where all the containers are? If it's via Redis, I would've thought that I'll need to tell the containers where the Redis instance is?
Update
I've tried running xd-admin and Redis on one box, and xd-container on another with redis.properties updated to point to the admin box. The container starts without reporting any exceptions.
Running the example stream submission curl -d "time | log" http://{admin IP}:8080/streams/ticktock yields no output to either console, and not output to the logs.
If you are using the xd-container script, then the redis.properties is expected to be under "XD_HOME/config" where XD_HOME points the base directory where you have bin, config, lib & modules of xd.
Communication between the Admin and Container runtime components is via the messaging bus, which by default is Redis.
Make sure the environment variable XD_HOME is set as per the documentation; if it is not you will see a logging message that suggests the properties file has been loaded correctly when it has not:
13/06/24 09:20:35 INFO support.PropertySourcesPlaceholderConfigurer: Loading properties file from URL [file:../config/redis.properties]

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