I have a CakePHP 1.2 application that makes a number of AJAX calls using the AjaxHelper object. The AjaxHelper makes a call to a controller function which then returns some data back to the page.
I would like to log the SQL queries that are executed by the AJAX controller functions. Normally, I would just turn the debug level to 2 in config/core.php, however, this breaks my AJAX functionality because it causes the output SQL queries to be appended to the output that is returned to the client side.
To get around this issue, I would like to be able to log any SQL queries performed to a log file. Any suggestions?
I found a nice way of adding this logging functionality at this link:
http://cakephp.1045679.n5.nabble.com/Log-SQL-queries-td1281970.html
Basically, in your cake/libs/model/datasources/dbo/ directory, you can make a subclass of the dbo that you're using. For example, if you're using the dbo_mysql.php database driver, then you can make a new class file called dbo_mysql_with_log.php. The file would contain some code along the lines of the following:
App::import('Core', array('Model', 'datasource', 'dbosource', 'dbomysql'));
class DboMysqlWithLog extends DboMysql {
function _execute($sql) {
$this->log($sql);
return parent::_execute($sql);
}
}
In a nutshell, this class modifies (i.e. overrides) the _execute function of the superclass to log the SQL query before doing whatever logic it normally does.
You can modify your app/config/database.php configuration file to use the new driver that you just created.
This is a fantastic way to debug things like this, https://github.com/cakephp/debug_kit
Related
I have used many discord API wrappers, but as an experienced python developer, unfortunately I somehow still do not understand how a command gets called!
#client.command()
async demo(ctx):
channel = ctx.channel
await channel.send(f'Demonstration')
Above a command has been created (function) and it is placed after its decorator #client.command()
To my understanding, the decorator is in a way, a "check" performed before running the function (demo) but I do not understand how the discord.py library seemingly "calls" the demo function.....?? Is there some form of short/long polling system in the local imported discord.py library which polls the discord API and receives a list of jobs/messages and checks these against the functions the user has created?
I would love to know how this works as I dont understand what "calls" the functions that the user makes, and this would allow me to make my own wrapper for another similar social media platform! Many thanks in advance.
I am trying to work out how functions created by the user are seemingly "called" by the discord.py library. I have worked with the discord.py wrapper and other API wrappers before.
(See source code attached at the bottom of the answer)
The #bot.command() decorator adds a command to the internal lists/mappings of commands stored in the Bot instance.
Whenever a message is received, this runs through Bot.process_commands. It can then look through every command stored to check if the message starts with one of them (prefix is checked beforehand). If it finds a match, then it can invoke it (the underlying callback is stored in the Command instance).
If you've ever overridden an on_message event and your commands stopped working, then this is why: that method is no longer being called, so it no longer tries to look through your commands to find a match.
This uses a dictionary to make it far more efficient - instead of having to iterate over every single command & alias available, it only has to check if the first letters of the message match anything at all.
The commands.Command() decorator used in Cogs works slightly different. This turns your function into a Command instance, and when adding a cog (using Bot.add_cog()) the library checks every attribute to see if any of them are Command instances.
References to source code
GroupMixin.command() (called when you use #client.command()): https://github.com/Rapptz/discord.py/blob/24bdb44d54686448a336ea6d72b1bf8600ef7220/discord/ext/commands/core.py#L1493
As you can see, it calls add_command() internally to add it to the list of commands.
Adding commands (GroupMixin.add_command()): https://github.com/Rapptz/discord.py/blob/24bdb44d54686448a336ea6d72b1bf8600ef7220/discord/ext/commands/core.py#L1315
Bot.process_commands(): https://github.com/Rapptz/discord.py/blob/master/discord/ext/commands/bot.py#L1360
You'll have to follow the chain - most of the processing actually happens in get_context which tries to create a Context instance out of the message: https://github.com/Rapptz/discord.py/blob/24bdb44d54686448a336ea6d72b1bf8600ef7220/discord/ext/commands/bot.py#L1231
commands.Command(): https://github.com/Rapptz/discord.py/blob/master/discord/ext/commands/core.py#L1745
I'm playing around with SqlDelight using MySql with Hikary datasource in a plain JVM project using Kotlin and Flow to consume queries results.
The first execution of a query returns the data as expected, however the Flow#emit() is not triggered when the data on the database changes.
This one is the repository function I'm invoking:
fun getAllUser(): Flow<List<User>> = database.userQueries.getAll()
.asFlow()
.mapToList()
This is the main function where the repository function is invoked:
fun main() = runBlocking<Unit> { repository.getAllUser().collect {
println("Collecting users: $it")
}
}
I've tried debugging the underling code and the listener on the Query object is registered and the main is correctly blocked on the execution of the repository function.
Anyone else has experienced something similar?
So stupid, my bad! I was updating the database manually and expecting to see the Flow magically updating. Anyway, updating the database by means of SqlDelight functions causes the Flow to emit the updated recordset as expected.
I am using SSIS 2012 and i need to figure out the best way to load multiple configuration files to be used in a custom script.
This is the way it goes:
I need to use a custom script to access a NoSQL database
In this case, the NoSQL database has no rigid schema, therefore the attribute change from document to document
I want to use configuration files to tell how the columns are supposed to be renamed and configure there other basic rules.
the above task is easily done in c#, however if possible i would like read the configuration files using a SSIS component (to read a flat file, excel file or database rules). Therefore i want to know how can i feed the custom script with the data from the stream, the scipt consumes stream (the stream contains the configuration), and after consuming the entire stream, the script component generates rows.
An example case would be be:
script reads an entire stream of numbers.
the script orders the numbers on the stream
the script discards duplicates the script
outputs the ordered sequence of numbers without duplicates.
If I understood correctly, the NoSql database and configuration files just background of the problem and what you really need is an asynchronous
script component to read everything from the pipeline, then do something and finally send the results back to the pipeline?
If so then what you need is create an script component with it's output buffer set to SynchronousInputId=None.
The example of the numbers to be deduped and sorted that you posted could then be solved with the following pseudo-code
(assume you create an output column in the output buffer of the script component called "numberout"
and output buffer property SynchronousInputId is set to None) :
...
public override void PreExecute()
{
base.PreExecute();
CREATE ARRAY TO HOLD NUMBERS
}
public override void PostExecute()
{
base.PostExecute();
SORT AND DEDUPE ARRAY
FOR EACH N IN ARRAY:
output0buffer.addrow()
output0byffer.numberout=N
}
public override void Input0_ProcessInputRow(Input0Buffer Row)
{
INSERT NUMBER TO ARRAY
}
I have a project in Apps script that uses several libraries. The project needed a more complex logger (logging levels, color coding) so I wrote one that outputs to google docs. All is fine and dandy if I immediately print the output to the google doc, when I import the logger in all of the libraries separately. However I noticed that when doing a lot of logging it takes much longer than without. So I am looking for a way to write all of the output in a single go at the end when the main script finishes.
This would require either:
Being able to define the logging library once (in the main file) and somehow accessing this in the attached libs. I can't seem to find a way to get the main projects closure from within the libraries though.
Some sort of singleton logger object. Not sure if this is possible from with a library, I have trouble figuring it out either way.
Extending the built-in Logger to suit my needs, not sure though...
My project looks at follows:
Main Project
Library 1
Library 2
Library 3
Library 4
This is how I use my current logger:
var logger = new BetterLogger(/* logging level */);
logger.warn('this is a warning');
Thanks!
Instead of writing to the file at each logged message (which is the source of your slow down), you could write your log messages to the Logger Library's ScriptDB instance and add a .write() method to your logger that will output the messages in one go. Your logger constructor can take a messageGroup parameter which can serve as a unique identifier for the lines you would like to write. This would also allow you to use different files for logging output.
As you build your messages into proper output to write to the file (don't write each line individually, batch operations are your friend), you might want to remove the message from the ScriptDB. However, it might also be a nice place to pull back old logs.
Your message object might look something like this:
{
message: "My message",
color: "red",
messageGroup: "groupName",
level: 25,
timeStamp: new Date().getTime(), //ScriptDB won't take date objects natively
loggingFile: "Document Key"
}
The query would look like:
var db = ScriptDb.getMyDb();
var results = db.query({messageGroup: "groupName"}).sortBy("timeStamp",db.NUMERIC);
Scenario: I am using Managed Extensibility Framework to load plugins (exports) at runtime based on an interface contract defined in a separate dll. In my Visual Studio solution, I have 3 different projects: The host application, a class library (defining the interface - "IPlugin") and another class library implementing the interface (the export - "MyPlugin.dll").
The host looks for exports in its own root directory, so during testing, I build the whole solution and copy Plugin.dll from the Plugin class library bin/release folder to the host's debug directory so that the host's DirectoryCatalog will find it and be able to add it to the CompositionContainer. Plugin.dll is not automatically copied after each rebuild, so I do that manually each time I've made changes to the contract/implementation.
However, a couple of times I've run the host application without having copied (an updated) Plugin.dll first, and it has thrown an exception during composition:
Unable to load one or more of the requested types. Retrieve the LoaderExceptions for more information
This is of course due to the fact that the Plugin.dll it's trying to import from implements a different version of IPlugin, where the property/method signatures don't match. Although it's easy to avoid this in a controlled and monitored environment, by simply avoiding (duh) obsolete IPlugin implementations in the plugin folder, I cannot rely on such assumptions in the production environment, where legacy plugins could be encountered.
The problem is that this exception effectively botches the whole Compose action and no exports are imported. I would have preferred that the mismatching IPlugin implementations are simply ignored, so that other exports in the catalog(s), implementing the correct version of IPlugin, are still imported.
Is there a way to accomplish this? I'm thinking either of several potential options:
There is a flag to set on the CompositionContainer ("ignore failing imports") prior to or when calling Compose
There is a similar flag to specify on the <ImportMany()> attribute
There is a way to "hook" on to the iteration process underlying Compose(), and be able to deal with each (failed) import individually
Using strong name signing to somehow only look for imports implementing the current version of IPlugin
Ideas?
I have also run into a similar problem.
If you are sure that you want to ignore such "bad" assemblies, then the solution is to call AssemblyCatalog.Parts.ToArray() right after creating each assembly catalog. This will trigger the ReflectionTypeLoadException which you mention. You then have a chance to catch the exception and ignore the bad assembly.
When you have created AssemblyCatalog objects for all the "good" assemblies, you can aggregate them in an AggregateCatalog and pass that to the CompositionContainer constructor.
This issue can be caused by several factors (any exceptions on the loaded assemblies), like the exception says, look at the ExceptionLoader to (hopefully) get some idea
Another problem/solution that I found, is when using DirectoryCatalog, if you don't specify the second parameter "searchPattern", MEF will load ALL the dlls in that folder (including third party), and start looking for export types, that can also cause this issue, a solution is to have a convention name on all the assemblies that export types, and specify that in the DirectoryCatalog constructor, I use *_Plugin.dll, that way MEF will only load assemblies that contain exported types
In my case MEF was loading a NHibernate dll and throwing some assembly version error on the LoaderException (this error can happen with any of the dlls in the directory), this approach solved the problem
Here is an example of above mentioned methods:
var di = new DirectoryInfo(Server.MapPath("../../bin/"));
if (!di.Exists) throw new Exception("Folder not exists: " + di.FullName);
var dlls = di.GetFileSystemInfos("*.dll");
AggregateCatalog agc = new AggregateCatalog();
foreach (var fi in dlls)
{
try
{
var ac = new AssemblyCatalog(Assembly.LoadFile(fi.FullName));
var parts = ac.Parts.ToArray(); // throws ReflectionTypeLoadException
agc.Catalogs.Add(ac);
}
catch (ReflectionTypeLoadException ex)
{
Elmah.ErrorSignal.FromCurrentContext().Raise(ex);
}
}
CompositionContainer cc = new CompositionContainer(agc);
_providers = cc.GetExports<IDataExchangeProvider>();