Wow, long time no blog post, huh? Here’s a quick tip how to stream a (presumably large) file to your client with Symfony without the need to load the file into memory.
<?php $file = '/tmp/a-large-file.jpg'; $format = pathinfo($file, PATHINFO_EXTENSION); return new \Symfony\Component\HttpFoundation\StreamedResponse( function () use ($file) { readfile($file); }, 200, array('Content-Type' => 'image/' . $format) );
Sources
To enable the debug tag in Twig, add the following to app/config/config_dev.yml
services: twig.extension.debug: class: Twig_Extensions_Extension_Debug tags: - { name: twig.extension }
Afterwards clear the cache and use the debug extension:
{% debug my_var %}
Sources
I just had some troubles to get adb to work together with my HTC Desire on Windows 7 64-Bit. When attaching the phone in USB debugging mode, it showed up as “My HTC” device, but adb couldn’t connect to it.
First of all, you need to install HTC Sync and the included USB drivers to get your device working normally with your computer (e.g. showing up as disk drive). Then install the Android SDK and the USB drivers package (from SDK manager) and add the following lines to the file extras\google\usb_driver\android_winusb.inf inside the [Google.NTamd64] section (before [USB_Install] around line 65):
;HTC Desire %CompositeAdbInterface% = USB_Install, USB\VID_0BB4&PID_0C87&MI_01
Use this driver for the “My HTC” device. It should install, show up as “Android Composite ADB Interface” afterwards and work with adb (do an adb devices to check).
Sources
A logcheck ignore pattern to filter out shorewall REJECT and DROP entries (net is defined as eth0). /etc/logwatch/ignore.d.server/shorewall:
^\w{3} [ :[:digit:]]{11} [._[:alnum:]-]+ kernel:( \[ *[[:digit:]]+\.[[:digit:]]+\])? Shorewall:net2([a-z0-9]*):(REJECT|DROP)
Test if the regex works for your config:
sed -e 's/[[:space:]]*$//' /var/log/syslog | egrep '^\w{3} [ :[:digit:]]{11} [._[:alnum:]-]+ kernel:( \[ *[[:digit:]]+\.[[:digit:]]+\])? Shorewall:net2([a-z0-9]*):(REJECT|DROP)'
An example how to install a Windows Server 2008 guest on KVM with VirtIO (on a LVM volume in the example). Besides the installation medium you need the VirtIO drivers for windows in order to be able to access the disk device. You can get signed binary drivers here. Then set up a Windows VM with a command like this:
$ virt-install --connect qemu:///system --arch=x86_64 -n win2k8 -r 1024 --vcpus=2 \ --disk pool=vmstore,size=50,bus=virtio,cache=none -c /path/to/win2k8.iso --vnc \ --noautoconsole --os-type windows --os-variant win2k8 --network network=subnet,model=e1000 \ --disk path=/path/to/virtio-win-1.1.16.iso,device=cdrom,perms=ro
When the guest is running, shut it down and edit the os section of the XML file to look like this (otherwise Windows setup won’t let you install on the disk):
$ virsh destroy win2k8 $ virsh edit win2k8
Change the XML as follows:
<os> ... <boot dev='cdrom'/> <boot dev='hd'/> </os>
Start the guest again:
$ virsh start win2k8
Connect to the VNC console and start the installation process. When you reach the form to select a disk device you won’t see any devices available. Click on “Load drivers” at the bottom left and load the drivers from E:\viostor\wlh\{amd64|x86}. After the drivers are installed, you’ll see a disk device and can continue with the installation.
Sources
Quite some time ago I wrote a tutorial on how to integrate fetchmail and sieve into virtual mail with Postfix and Dovecot. As time passes and things change, here’s an update:
- I don’t use the sieve part anymore. Instead, I use the ManageSieve server provided by Dovecot. It integrates with Dovecot’s authentication system and you can use all kinds of clients supporting the managesieve protocol, e.g. Thunderbird or Roundcube.
- The ISPMail database structure changed since I wrote that tutorial which still relied on the DB structure for the Debian Etch structure. I updated the script to reflect both environments (take a look at the config file). However, it does not rely on any DB views anymore.
- The script (only the Fetchmail part) is now hosted on GitHub as I rarely use SVN anymore and the SVN may go offline in the near future. If anybody is interested in the Sieve part, just drop me a line.
I recently needed to restore data from a MySQL server where the host machine crashed and where I unfortunately didn’t have a proper dump backup – all I had was a backup of the MySQL data directory (/var/lib/mysql in case of Debian). After some googling I didn’t find a simple solution how to restore databases out of this backup. The solution which worked in the end was the following: I installed a fresh MySQL server in a virtual machine and replaced its data directory with the one from my backup (I had exactly the same MySQL versions on both machines). This allowed me to access the databases and create proper dumps which I could import in my real server later.
So, step one: in a virtual machine/spare server/local pc/whatever install a MySQL server and replace its data directory:
$ aptitude install mysql-server $ /etc/init.d/mysql stop $ mv /var/lib/mysql /var/lib/mysql.orig $ cp -pr /tmp/backup/mysql /var/lib $ chown -R mysql.mysql /var/lib/mysql
I also checked that file permissions match the normal permissions on Debian MySQL installations. Should be like this:
root@host:/var/lib/mysql# ls -al drwx------ 5 mysql mysql 4096 Mar 1 18:20 . drwxr-xr-x 33 root root 4096 Mar 1 18:20 .. -rw-r--r-- 1 root root 0 Mar 1 18:07 debian-5.1.flag -rw-rw---- 1 mysql mysql 27262976 Mar 1 18:21 ibdata1 -rw-rw---- 1 mysql mysql 5242880 Mar 1 18:21 ib_logfile0 -rw-rw---- 1 mysql mysql 5242880 Mar 1 18:21 ib_logfile1 drwx------ 2 mysql mysql 4096 Mar 1 18:20 database1 drwx------ 2 mysql mysql 4096 Mar 1 18:21 database2 drwx------ 2 mysql root 4096 Mar 1 18:08 mysql -rw------- 1 root root 6 Mar 1 18:08 mysql_upgrade_info
root@host:/var/lib/mysql# ls -al database1 drwx------ 2 mysql mysql 4096 Mar 1 18:20 . drwx------ 5 mysql mysql 4096 Mar 1 18:20 .. -rw-rw---- 1 mysql mysql 65 Mar 1 18:20 db.opt -rw-rw---- 1 mysql mysql 8668 Mar 1 18:20 table1.frm -rw-rw---- 1 mysql mysql 879 Mar 1 18:20 table2.frm -rw-rw---- 1 mysql mysql 1520 Mar 1 18:20 table3.frm
Now you can try to start the server and look if your databases are readable:
$ /etc/init.d/mysql start $ mysql -uroot -p -e "show databases;" Enter password: +--------------------+ | Database | +--------------------+ | information_schema | | database1 | | database1 | | mysql | +--------------------+
If this works, simply dump your needed databases with mysqldump, transfer them to your server and import them normally.
$ mysqldump -uroot -p database1 > /tmp/database1.sql $ scp /tmp/database1.sql user@server:/tmp
On the server:
$ mysql -uroot -p -e "create database database1;" $ mysql -uroot -p database1 < /tmp/database1.sql
And don’t forget to restore the temporary MySQL server to normal operation in case you need it later.
$ /etc/init.d/mysql stop $ rm -rf /var/lib/mysql $ mv /var/lib/mysql.orig /var/lib/mysql $ /etc/init.d/mysql start
A short howto how to use a LVM volume group with libvirt on Debian Squeeze (used for KVM VMs in my case). I assume your VG already exists and is dedicated for libvirt usage. In my case it’s /dev/vg1.
First of all, create the XML definition for the storage pool in /etc/libvirt/storage/vg1.xml. This is the minimal configuration needed, libvirt will extend it with things like UUID when you define it.
<pool type='logical'> <name>vg1</name> <target> <path>/dev/vg1</path> </target> </pool>
Now you can tell libvirt about the new storage pool and let it start automatically.
$ virsh pool-define /etc/libvirt/storage/vg1.xml $ virsh pool-start vg1 $ virsh pool-autostart vg1 $ virsh pool-info vg1
Creating virtual machines inside that storage pool is easy as pie:
$ virt-install -d --hvm --vnc --name=vm01 \
--ram 512 --disk pool=vg1,size=10,bus=virtio,cache=none \
--network network=default,model=virtio \
--location=http://ftp.debian.org/debian/dists/squeeze/main/installer-amd64/ \
--os-type=linux --os-variant=debiansqueeze
Cheers!
It took me some time to figure out how to access and change a user account in eZPublish from PHP. Here’s an example how to achieve this:
<?php // user node $node = eZContentObjectTreeNode::fetch($nodeID); // user object $dataMap = $node->dataMap(); // change attribute $firstname = $dataMap['firstname']; $firstname->setAttribute('data_text', 'Foo'); $firstname->sync(); // user account attribute $user = $dataMap['user_account']; $userData = $user->content(); // user settings $userSetting = eZUserSetting::fetch($user->ContentObjectID); // get account status $isEnabled = $userSetting->attribute('is_enabled'); // enable user account $userSetting->setAttribute('is_enabled', 1); $userSetting->store();
Or if you just want to access the user account object or the user setting directly:
<?php // user account object $user = eZUser::fetch($objectID); // user settings $userSetting = eZUserSetting::fetch($objectID);
I’m currently working on a bigger paper for university using LaTeX. As it’s necessary to compile source files multiple times (especially when using BibTeX or TOCs), build runs can take quite some time. As an example, my current build script:
#!/bin/bash BN=paper pdflatex -interaction=nonstopmode $BN.tex bibtex $BN pdflatex -interaction=nonstopmode $BN.tex bibtex $BN pdflatex -interaction=nonstopmode $BN.tex makeindex -s $BN.ist -t $BN.glg -o $BN.gls $BN.glo pdflatex -interaction=nonstopmode $BN.tex pdflatex -interaction=nonstopmode $BN.tex rm -rf $BN.aux rm -rf $BN.lof rm -rf $BN.lot rm -rf $BN.out rm -rf $BN.toc rm -rf $BN.bbl rm -rf $BN.blg rm -rf $BN.brf rm -rf $BN.idx rm -rf $BN.glo rm -rf $BN.ist rm -rf $BN.glg rm -rf $BN.gls rm -rf texput.log
This is OK on my workstation, but running a build on my notebook using a small 1.4 GHz single core processor can take up to a minute which is definitely too long. So I looked for solutions how to move the build process to a central server. As I was already using Git for source control on the project, I tried setting up a remote repository on the server which triggered a build using a post-receive script. This basically worked fine, but I wanted to go a step further. I had a look at CI servers and gave Hudson a try as it seems to have a lot of features while being quite easy to set up.
The result is the following: Hudson is polling the Git repository (can be remote or local, in my case it’s a self-hosted remote gitosis installation, but could be github too), starting a new build on changes and publishing the resulting PDF if successful. Hudson is accessible over https using an Apache2 server as frontend to a Tomcat installation.
Ready? Let’s go.
