Projects on Hyteck

Rules, Terms and Privacy for GoToSocial: gay-pirate-assassins.de

2022-11-20T04:56:10+02:00

Rules

"Be excellent to each other" is easier said than done, and means different things to different people.

The following rules are a (non-exhaustive) list of behaviours that may lead to deletion of toots, silencing or suspension of accounts, at the descretion of the instance administrators, as described in our Terms

Please report behaviour that bothers you. We will keep your report confidential.

We do not tolerate discriminatory behaviour and content promoting or advocating the oppression of members of marginalised groups. These groups may be characterised by any of the following (though this list is naturally incomplete):
- ethnicity
- gender identity or expression
- sexual identity or expression
- physical characteristics or age
- disability or illness
- nationality, residency, citizen status
- wealth or education
- religious affiliation, agnosticism or atheism
We do not tolerate threatening behaviour, stalking, and doxxing
We do not tolerate harassment, including brigading, dogpiling, or any other form of contact with a user who has stated that they do not wish to be contacted.
We do not tolerate mobbing, including name-calling, intentional misgendering or deadnaming.
We do not tolerate violent nationalist propaganda, Nazi symbolism or promoting the ideology of National Socialism.
We do not tolerate conspiracy narratives or other reactionary myths supporting or leading to the above-mentioned (and/or similar) behavior.
Actions intended to damage this instance or its performance may lead to immediate account suspension.
Content that is illegal in Germany will be deleted and may lead to immediate account suspension.

Best practices

The list below is a collection of behaviour that we expect to see from our users. If you see a user go against these best practices in a way that bothers you, please file a report and we will talk to them. While these best practices are designed to be guidelines for a good communal instance, repeated malicious unwillingness to follow the best practices will be considered just like breaking a rule.

In general, use the tools provided to foster a considerate and accessible atmosphere. This includes the liberal use of content warnings (especially on potentially disturbing or controversial topics), and alt-text captioning of media files.
When possible, provide credit for creative works in your posts that are not your own.
Uninvited comments about another user's personal choices, lifestyle or family are strongly discouraged and may be considered harassment. Inappropriate sexual attention, comments about appearance and implication of physical contact will not be tolerated toward any non-consenting user.
If you post sexual content or gore, use content warnings.
If you post advertisements, use a content warning. Advertisements should not be excessive or automated.
Bots may only interact with a user when they're invited by that user to do so.
Automated posts and high-frequency posts should be unlisted (rendering visible to everybody, but not appearing on the local timeline) to keep the local timeline of our instance a place of community dialogue and human interaction. This extends to bots, feed posters, Twitter "retweets" and Twitter crossposts with broken mentions ("…@twitter.com"). Crossposter accounts that stop being active participants in our community may be removed at the discretion of the moderators.
In discussions, please remain civil, do not insult the people you're talking to. Note that irony, sarcasm, or similar modes of language don't translate well to written language and tend to escalate discussions or misunderstandings.

(These best practices were inspired by the Terms of bsd.network. Thank you!)

Resources

I am maintaining this instance on my spare time, hardware and nerves. Don't push either of those.

Terms of Service

adapted from chaos.social which was in turn adepted by the bsd.network ToS

It is our intention that you use this service for personal enjoyment and respectful, friendly interaction. To that end, we hope to foster a welcoming and inclusive environment.

The server is privately owned and open to users voluntarily, not a public space. Users wishing to join this community are expected to act without malice and in good faith. Doing otherwise may lead to removal from the service, independent of whether a user violates any rules outlined below.

The administrators and moderators of this instance are

moanos

The server hosting the instance is located in Germany.

The following statements apply regardless of privacy level and instance of the users involved. In rare cases, public or private offline conduct or conduct on a separate instance may constitute grounds for removal from the service.

Policies and Rules

Our instance is subject to a set of rules governing user behaviour. The rules are defined above.

These rules are designed to maintain a friendly and open atmosphere, and to prevent harassment and discrimination. As such, they are a set of guidelines, but by necessity incomplete. Users violating the spirit of these rules will be treated no differently than users violating a specific rule.

Please note that our rules contain a section on best practices, and users who repeatedly and despite warnings disregard these best practices may be seen to be in violation of our rules.

The moderators may remove accounts who spam the instance, or are suspected of camping just to reserve an account name. Violation of the policies and rules may also lead to account removal at the discretion of the moderators.

Data Access

Content on this instance must not be used for the purposes of machine learning or other "research" purposes without the explicit consent of the users involved.

Content on this instance beyond this page must not be archived or indexed wholesale by automated means by any user or service. Active users may export their following lists and posts through the export provided on their settings page, or the API.

Privacy Policy

Information collection

Mandatory account information: Username (always public), e-mail address, and password.
Optional account information: Display name, biography, profile information fields, profile picture, and header image. Display name, biography, profile picture and header image will always be public.
Statuses and interactions: We retain all your posts including attachments, and other interactions (such as favourites, follows and reblogs). In addition to the content and people involved, we also store the timestamps for all of the listed data entries. If these interactions impact another server (eg. following, boosting, or messaging a user on a different server), this other server will receive all required information. Public, unlisted, and pinned posts are available publicly. Follower-only posts are available to your followers, and direct messages are available to you and all people mentioned in the message. Please note that since we cannot control other servers, this means that we cannot guarantee the privacy status of your messages as soon as they leave our server.
Cookies: We use cookies to keep you logged in and save your preferences for future visits.
Other metadata: We do log and store your IP address. We retain the name of your browser application to allow you to review your currently logged in sessions for security reasons.

Information usage

Any of the information we collect from you may be used in the following ways:

To provide the core functionality of GoToSocial. You can only interact with other people's content and post your own content when you are logged in. For example, you may follow other people to view their combined posts in your own personalized home timeline.
To aid moderation of the community – when a status or account is reported, we will look into the matter as part of our moderation tasks.
The email address you provide may be used to send you information, notifications about other people interacting with your content or sending you messages, and to respond to inquiries, and/or other requests or questions.
To aid debugging and reliable providing service.

Information protection

We implement a variety of security measures to maintain the safety of your personal information when you enter, submit, or access your personal information. Among other things, your browser session, as well as the traffic between your applications and the API, are secured with HTTPS, and your password is hashed using a strong one-way algorithm. You may enable two-factor authentication to further secure access to your account.

Information deletion and retention

You can request and download an archive of your content, including your posts, media attachments, profile picture, and header image.

You may irreversibly delete your account at any time.

If we judge you to be breaking our instance rules, we may irreversibly delete your account at any time.

Information disclosure

Information is not disclosed unless you explicitly permit it. The only exception is the provider of our server, who is a trusted and unavoidable third party.

Contacting or permitting contact from a user from a different instance implies your consent that the required data is shared with the server in question.

Authorization of a third-party application grants information access depending on the scope of permissions you approve. The application may access your public profile information, your following list, your followers, your lists, all your posts, and your favourites. Applications can never access your e-mail address or password.

Attribution ¶

This text was adapted from https://chaos.social/about and is free to be adapted and remixed under the terms of the CC-BY (Attribution 4.0 International).

Disappearing messages with matrix

2021-12-31T20:00:00+02:00

Introduction

I am a HUGE fan of matrix. It allows me to organize my chats in a sensible way, it works with multiple identities and completly anonymous if I want it to. Spaces made Matrix my favourite messenger by far. Yet, there is one feature I have been missing: Disappearing messages!

Regarding the security and usability, only Signal is comparable to matrix. But: Signal offers the possibilty to define disappearing messages for groups and direct messages ranging from 30 seconds to 4 weeks. No Matrix client (to my knowledge) offers this functionality. Nevertheless, it is possible to configure matrix rooms to have the same feature. This needs a special server configuration and the sending of a special event in the room. This post tries to show both steps. If you do not administer a server you can probably skip to Room configuration

Be aware that this blogpost was written at the end of 2021 - Matrix develops fast and this could be subejct to changes.

Instance configuration

To make disappearing messages possible you need to enable retention on your matrix instance. Retention allows server and room admins to configure how long messages should be kept in the instances database before being purged from it. It is not part of the matrix specification, yet it is supported by synapse.

A client SHOULD not display these messages anymore after the max_lifetime is exceeded. This was NOT true for element web an desktop while staying logged in. Nevertheless, a newly logged in client did not have access to the messages.

To configure Synapse to make use of retention you will need to enable it in your homeserver.yaml

retention:
enabled: true # enables the retention, is enough to enforce it once per day
purge_jobs: # configures a job that delete the events from the database after some tome
- longest_max_lifetime: 3d
interval: 1h
- shortest_max_lifetime: 3d
interval: 1d

The example configuration creates two jobs that delete messages from the database. One only focuses on events that should be deleted after three days or less. These events will be deleted every hour. It is therefore possible for a message that was send in a room with a max_lifetime=7200000 (equals 2h) to be deleted one hour after the maximum lifetime.

Ansible

If you use the Ansible/Docker setup to deploy your server you can add the following to inventory/host_vars/matrix.example.com/vars.yml

matrix_synapse_configuration_extension_yaml: |
retention:
enabled: true
purge_jobs:
- longest_max_lifetime: 1d
interval: 2h
- shortest_max_lifetime: 1d
interval: 1d

Room configuration

If you are a user on a server that has retention enabled, you can enable disappearing messages yourself for each room. Sadly, this is still experimental - but managable! You have to craft a m.room.retention event that defines the maximum lifetime of a message. You will need to access the rooms settings in order to do this.

First you need to open the developer tools in the rooms settings.

Then click “Send custom event” to create your event

And fill the event with the appropriate max_liftime. The time is an integer in milliseconds. X hours is therefore a value of X*3 600 000. Make sure to click the red event button. The State Key can be left empty nevertheless.

Depending on your choosen lifetime the client should not show the messages anymore.

Limitations

The process of deleting messages can not be enforced. A malicious server or chat partner could ignore the request to delete the messages or they could have saved them elsewere. You should not rely on a deletion actually happening. Nevertheless I think this is a good step to take to improve your security in real life.

Further Information

Relevant part of the Synapse configuration file: https://github.com/matrix-org/synapse/blob/v1.36.0/docs/sample_config.yaml#L451-L518
Synapse documenation on message retention policies https://matrix-org.github.io/synapse/v1.41/message_retention_policies.html

What else?

Thanks to Tastytea for helping me get this to work!

Comments

If you have questions, corrections or want to leave something else, please feel free to use the comments!

Cactus comments via Matrix

2021-08-25T11:08:55+02:00

Integration

Following the quickstart documentation I tried to add cactus comments to this blog. I currently rely on infrastructure by cactus.chat as I do not host a private synapse server.

I currently implemented this as a shortcode with hard-coded site title and a variable room name.

Quickstart with HUGO

Register your site

There is a registration system, that ensures that you are moderater in your comment section(s). I order to register your site you have to send a message to @cactusbot:cactus.chat . First try help to ensure that the bot answers you, then register your site e.g. register hyteck. The bot should inform you of success and add you to a moderation room.

Embedd comment section via Shortcode

HUGO, the static site generator I use, has an option to use shortcodes that provide a nice interface to hide some HTML, CSS and JavaScript.

The shortcode chat.html must be added to layouts/shortcodes/ and looks like this

<script type="text/javascript" src="https://latest.cactus.chat/cactus.js"></script>
<link rel="stylesheet" href="https://latest.cactus.chat/style.css" type="text/css">
<div id="comment-section"></div>
<script>
initComments({
node: document.getElementById("comment-section"),
defaultHomeserverUrl: "https://matrix.cactus.chat:8448",
serverName: "cactus.chat",
siteName: "hyteck",
commentSectionId: "{{ index .Params 0 }}"
})
</script>

If you want to use this, replace the site name with the one you registered in the previous step.

You can then use it as simple as

{{< chat cactus-comments >}}

where cactus-comments is the name of the chatroom. You can decide if you want to create a new one for each post (change the name to somthing like the post title) or if you want to use only one (keep the same name).

Organisation

I try to make a comment with my main matrix account, so that I am automatically joined to the room (tbh. I don’t know if this is necessary). Then I organize the rooms by adding them to a private space.

Community

CW: Homophobia, Slur

The community in the official chat seemed helpful and nice. Nevertheless I want to mention, that the first time I tried the demo page a user (that does not seem to be associated with the develoipment or involved in the community) insulted me with a homophobic slur. The “reason” behind this were the prounouns I had in my name. I reported the comment and it was removed by a moderator. The moderator made it clear that this behaviour is agains the Code of Conduct and that the user is not active in the community. For me this is a very good indication of a functioning community, cheers!

Comments

Owncast & Streaming a talk

2021-05-20T16:08:55+02:00

I recently installed an Owncast server and wanted to share my experience. Here it is:

What is owncast?

Owncast is a streaming server that you can selfhost, a Twicht in a box as the developers call it. You host owncast on your server (a small VM with good downlink is enough) and can stream your own own content like you would do on Twicht, YouTube etc…

It has a chat, a admin panel for customization and thats it! You don’t need more to e.g. stream while you are playing minecraft or want to share a talk.

Getting started

Get the latest release on GitHub by using

$ mkdir owncast
$ cd owncast
$ wget https://github.com/owncast/owncast/releases/download/v0.0.7/owncast-0.0.7-linux-64bit.zip
$ unzip owncast-0.0.7-linux-64bit.zip
$ rm owncast-0.0.7-linux-64bit.zip

And move the webroot to your document root and make sure the permissions fit

$ cd ..
$ mv owncast /var/www/owncast
$ cd /var/www/
$ chown -R www-data:www-data owncast

Now create a new NGINX site e.g. /etc/nginx/sites-enabled/owncast with the following content

map $http_upgrade $connection_upgrade {
default upgrade;
'' close;
}
server {
listen [::]:443 ssl ipv6only=on; # managed by Certbot
listen 443 ssl; # managed by Certbot
ssl_certificate /etc/letsencrypt/live/stream.hyteck.de/fullchain.pem; # managed by Certbot
ssl_certificate_key /etc/letsencrypt/live/stream.hyteck.de/privkey.pem; # managed by Certbot
include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot
server_name stream.hyteck.de;
# Set header
add_header X-Clacks-Overhead "GNU Terry Pratchett";
add_header Permissions-Policy interest-cohort=(); #Anti FLoC
location / {
proxy_set_header Host $host;
proxy_set_header X-Forwarded-Host $host;
proxy_set_header X-Forwarded-Server $host;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection $connection_upgrade;
proxy_pass http://127.0.0.1:8080;
}
}
server {
listen 80;
listen [::]:80;
server_name stream.hyteck.de;
return 301 https://$server_name$request_uri;
}

Make sure to adjust the server name and SSL certificats (I will not go into detail on how to obtain them, but feel free to ask me!).

Start server

Now start owncast to test

$ cd /var/www/owncast
$ ./owncast/owncast

and visit https://yourdomain.org! If everything works you should see your site now. By visiting https://yourdomain.org/admin you can configure your server. The default credentials are admin and your stream key which is abc123. Change this immediately!

Before you configure, let’s make sure this runs whenever your server starts. Goback in the terminal and cancel with Ctrl+C.

Run as system service

You want to install owncast as a system service. Therfore create /etc/systemd/system/owncast.service with the following content:

[Unit]
Description=Owncast
After=network.target
[Service]
Type=simple
Restart=always
RestartSec=1
WorkingDirectory=/var/www/owncast
ExecStart=/var/www/owncast/owncast
[Install]
WantedBy=multi-user.target

Update the daemon with systemctl daemon-reload enable systemctl enable owncast and start with systemctl start owncast. Make sure everything is correct with systemctl status owncast.

Configuration

You can now change back to yourdoiman.org/admin and configure, title, logo and more.

Streaming

You can now use OBS or similar software to start streaming. Got to settings and configure your server.

Concept for talks

To livestream we have a few important things to take care of:

The speaker
The presentation
The streaming software
The streaming server
The chat

I suggest the following setup. Moderation and Speaker are in a BigBlueButton conference. The meet 15 minutes in advance, enough time to upload a presentation. Also in this room is a user called stream. This user does only listen and has OBS configured to record audio and the (fullscreen) window of the BBB room.

Before the talk starts, it is a good opportunity to play some videos via the stream, or simply put on a picture, saing the talk will start soon.

When the speaker an moderation are ready they tell the streamer and the scene is switched to the BBB room. The recording is started (if needed).

A weakness of the setup is the streaner. If they loose their network connection, the stream stops.

There is a neat project for live streaming directly from a BBB room, but it is quite complicated to set up and a crash of the BBB server would make stop the stream. Also the start of the stream is not as beautiful.

Performance

It can be hard to estimate the needed server capacities for a livestream that is why I want to share my experiences. All of this was done on a Strato Linux V40 with 16 GB of RAM, 8 vCPUs and 500 MBit/s.

On the following screenshots you see the configuration and the monitoring data of a talk with 40 participants. We pplayed high-quality videos from 17:43 to 18:05. At 18:05 we changed to the presentation. You see the decrease in CPU load, as the compression of the videos was easier with a steady picture. At 19:05 we invited the participents to join us in the BBB room, some left the stream.

The network load scales linear with the participants that are watching. You can simply calculate the needed downlink capacity with

Downlink capacity = Num. participants x Outbound Video Stream Rate

Here this was

40 participants x 1200 kbps = 48 Mbps

which matches the observed network traffic quite well.

The CPU load is determined by the compression the server has to do. The more different stream formats the server has to put out, the higher the load becomes. On the given Screenshot you see that only one downlink format was advertised, so the inbound stream had to be compresse only once. Matching imbound and outbound stream formats help reducing the server load.

If your bottleneck is the bandwidth you can try to add a second low streamrate, maybe ome clients will take that one.

Final notes

Owncast is a great project. Be aware that it is still not in version 1.0 so expect some limitations. This is e.g. the unability to block a user from chat. If you have any questions let me know in the comments below.

Transparency

2021-02-08T15:00:10+02:00

Deutsch

Wir haben die bisherigen Kosten für Server-Hardware in der Tabelle unten angegeben. Das beinhaltet nicht die Kosten für die Domain und unseren Monitoring-Server.

An alle die bisher gespendet habe: Ganz ganz vielen Dank euch!

English

We summarized the cost of hardware in the table below. This does not include costs of the domain and our monitoring server.

To everyone that contributed: Thank you so so much!

Überblick/Overview

Kosten	Spenden	Saldo
-321.63 €	235.5 €	- 86.13 €

Kostenaufstellung / Exact cost

Date	Cost (€)
27.04.2021	-25
1.04.2021	-25
26.02.2021	-25
22.01.2021	-25
22.12.2020	-24.78
25.11.2020	-24.37
22.10.2020	-24.37
22.09.2020	-24.37
22.08.2020	-24.37
22.07.2020	-24.37
22.06.2020	-25
22.05.2020	-25
22.04.2020	-25
Total	-321.63

Die wechselnden monatlichen Kosten sind durch die temporär gesenkte Mehrwertsteuer bedingt.

The altering monthly costs are explained by a decrease in sales tax in Germany.

Spenden / Donations

Date	Donation (€)
03.05.2021	7.50
06.04.2021	7.50
02.03.2021	7.50
01.03.2021	100
12.02.2021	33
12.02.2021	20
09.02.2021	50
09.02.2021	10
Total	235.5

Letzte Aktualisierung / Last update

21.05.2021

Kontak / Contact

Bei Fragen meldet euch gerne bei: bbb@hyteck.de

If you have any questions regarding this ask us via: bbb@hyteck.de

Introduction to git

2019-10-22T19:00:00+02:00

As you man now I work in a research lab. Nearly everyone in our lab needs to do at least some programming. There are trained software engineers next to people how write their first line of code here. As we produce a lot of code that is only scripts not many people used git or any other version control system. For all the good reasons (some are mentioned in the guide) we everybody to learn git in a way that is tradeoff between good version control and fast development. As most of us work on separate projects there is not so much need to collaborate which is reflected ind this guide as I completely excluded branching and merge conflicts. Yet I hope this will maybe help some learners of git or some people that need to introduce git to others.

I will not be updating this guide, for the newest version please visit https://github.com/GerJuli/introduction-to-git

Now enjoy the guide!

Installation

On Windows: Download git here: https://git-scm.com/download/win and install it
On Linux: execute ‘sudo apt install git’ in the terminal

Configuration

Basics

$ git config --global user.name "John Doe"
$ git config --global user.email johndoe@example.com

Run these commands without –global to apply changes only for local repository.

Advanced

Change from default editor by executing $ git config --global core.editor vim
Create aliases by:
- git config --global alias.unstage 'reset HEAD --': Introduces new command unstage
- git config --global alias.hist 'log --pretty=format:"%h - %an, %ar : %s" --graph': Is an pretty alternative to git log.
Check the configuration by $ git config --list

Getting started

Create an directory

Select an directory of your choice e.g. ~/Desktop/git-training/, open the terminal there and type

$ git init

Congratulations you have your first git repository!

Committing files

Create some text files e.g. hallo.txt or hello_world.py. To start version-controlling them add the file to git by using the command

$ git add filename

You can also add multiple files. E.g. you want to add all text files the do

$ git add *.txt

Now we can commit these changes by typing

$ git commit

This will open your preferred text editor where you can type in a commit message.

Commit messages

Commit messages are important

Why are the so important? Because it is much easier to track bugs with it, they describe the process of development, make it easier for others to work with your code (e.g. code review) and will help you in two years to understand what you did. They extend your labbook in its function.

How to write commit messages

Use present tense and use imperative
Tell why you did changes.
Limit yourself to 50 characters in the first line.
Wrap the body at 72 characters

Good commit messages

For short commits that need only few explanation it is convenient to use

$ git commit -m "Fix typo in introduction to user guide"

For long commit message you use

$ git commit

which opens a text editor and lets you describe your changes in detail. Do not forget the line between header and body of the commit message.

Summarize changes in around 50 characters or less
More detailed explanatory text, if necessary. Wrap it to about 72
characters or so. In some contexts, the first line is treated as the
subject of the commit and the rest of the text as the body. The
blank line separating the summary from the body is critical (unless
you omit the body entirely); various tools like `log`, `shortlog`
and `rebase` can get confused if you run the two together.
Explain the problem that this commit is solving. Focus on why you
are making this change as opposed to how (the code explains that).
Are there side effects or other unintuitive consequences of this
change? Here's the place to explain them.
Further paragraphs come after blank lines.
- Bullet points are okay, too
- Typically a hyphen or asterisk is used for the bullet, preceded
by a single space, with blank lines in between, but conventions
vary here

Hall of shame

Here you see some examples of bad commit messages.

“bug fix”, “more work”, “minor changes”: Bad because it contains no useful information
“Change X constant to be 10”: Bad as it does not tell why. What was changed is easy to find out by git diff.
“super long commit message goes here, something like 100 words and lots of characters woohoo!”: Bad because it is unreadable.

Storing changes on remote server

To store changes on a remote server e.g. Github you need to push your repository there. If you are doing this for the first time you first need to define where to push your repository to. Use

$ git remote add origin https://github.com/GerJuli/introduction-to-git.git

The URL can be replaced with any URL that points to an existing repository. This can even be a USB drive! Now push by using git push -u origin master. With this command you created an upstream to your remote ‘origin’ where you branch ‘master’ will be pushed. As this is set up you can use git push from now on.

Cloning existing repositories

Downloading existing repositories is called ‘cloning’. You can do this by using

$ git clone https://github.com/GerJuli/introduction-to-git.git

That is it. Now you can start working on it.

Workflow

Check status

With

$ git status

you can check the status of your current directory. This will look like this:

$ git status
On branch master
Your branch is up-to-date with 'origin/master'.
nothing to commit, working directory clean

Add file

If you now add a file to the repository e.g. README then the status changes.

$ echo 'My Project' > README
$ git status
On branch master
Your branch is up-to-date with 'origin/master'.
Untracked files:
 (use "git add <file>..." to include in what will be committed)

 README

 nothing added to commit but untracked files present (use "git add" to track)

You can also run

$ git diff

which will show you the changes that where made.

Now track the file by adding it to the staging area via

$ git add README

If you want to commit only a part of the changes you made use

git add -p

git will ask you for every “hunk”(part of the file) if you want to add it to the staging area. The main options are:

y stage this hunk for the next commit
n do not stage this hunk for the next commit
q quit; do not stage this hunk or any of the remaining hunks

Committing

The changes are now ready to be committed

$ git status
On branch master
Your branch is up-to-date with 'origin/master'.
Changes to be committed:
 (use "git reset HEAD <file>..." to unstage)

 new file: README

Now commit this change with a suitable commit message. You forgot what you changed and git diff does not work? If you already added the file to the staging area you can run

$ git diff --staged

Push to remote

Push this now to your repository with

$ git push

Show last changes

$ git log

shows you a log of recent commit messages.

If you want to have a look at the changes source use

$ git log -p

A much prettier version is

$ git log --pretty=format:"%h - %an, %ar : %s" --graph

Get latest changes

An amazing thing of git is to work together with others. This guide will not go into the details of this, yet you will often have to get the latest changes of a project.

You can do this easily by using

$ git pull

which is a short version of two different commands. It first executes git fetch that downloads the latest changes. Then it runs git merge FETCH_HEAD which tries to apply the newest changes to your local repository. This is also the difficulty of this as any file that was changed locally and in the remote repository will cause a merge conflict as git does not know which file/parts of the file to keep. The resolution of such a conflict can be complicated and goes beyond the intentions of this guide.

A brief overview can be found here.

Gitignore

Sometimes you do not want git to track every file in your repository. Typically this applies for log files, configuration files (where maybe passwords are stored) and compiled sources. For this purpose you can create the file .gitignore in your repository. This file will be read by git. An example .gitignore looks like this:

# ignore all .log files
*.log
# ignore all files in any directory named config
build/
# but do track sample.log, even though you're ignoring .log files above
!sample.log
# only ignore the TODO file in the current directory, not subdir/TODO
/TODO
# ignore all files in any directory named build
build/

You can generate gitignore files here.

Undoing things

Make changes to the last commit

You forgot to add one file to your commit? You are unhappy with your commit message? Use git --amend!

$ git commit -m 'Pretty commit message'
$ git add forgotten_file
$ git commit --amend

Do not do this if you already pushed to remote.

Unmodifying a Modified File

You made changes to a file but the changes messed everything up? You can always go back to the version of the last commit by

git checkout -- filename

Warning: This is dangerous as you delete all changes that you made locally. Do NOT use this command unless you are absolutely sure what you are doing.

Time machine

Something went terribly wrong. When using git this is no problem. Just use reflog and select the commit where still everything was alright.

$ git reflog
9bff138 HEAD@{0}: commit: Document limitations of this guide
8d9dac8 HEAD@{1}: commit (amend): Adjust script to nice print
[...]
2b66f53 HEAD@{7}: commit: Introduce git log
8835c33 HEAD@{8}: commit: Fix of formating of headings
2f0f500 HEAD@{9}: commit: Improve order of comments on workflow
249dc14 HEAD@{10}: commit (amend): Explain git diff
f5ba1d3 HEAD@{11}: commit: Explain git diff
0a2ce1c HEAD@{12}: commit: Remove trailing whitspaces
735511f HEAD@{13}: commit (initial): Initial commit

$ git reset HEAD@{index_where_everything_was_fine}
$ git reset --hard origin/master

Warning: This is dangerous as you delete all changes that you made locally. Do NOT use this command unless you are absolutely sure what you are doing.

USB sticks as remote

Sometimes (e.g. you are working on a machine that is not connected to the internet) it can be helpful to use an USB drive as remote.

How to prepare the drive

Go to the USB drive

$ cd /media/username/git-stick/

Create a directory for your repository

$ mkdir my-repo

Initialize the repo

$ cd my-repo
$ git init --bare

How to push to a USB drive

To push to a USB drive you need to add a remote. Go to your local repository and use

$ git remote add usb /media/username/git-stick/my-repo/

Be aware that your stick will have a different name and will be at a different location, depending on your operating system. You named the remote “usb” here, of course you can change that name.

Now push your repo

$ git push usb

To list all repositories just type

$ git remote
origin
usb

If you want to push to the USB drive by default you can use

$ git push -u usb master
Branch 'master' set up to track remote branch 'master' from 'usb'

What this guide does not cover

Branching
- Creating branches
- Merging branches (and merge conflicts)
- Remote branches
- Tagging
- Forks
Usage of Github
Hooks

Logo

Git Logo by Jason Long

ILMO

2019-09-15T22:00:55+02:00

ILMO

is my first bigger FOSS-project. It aims at managing small libraries as found in a department of a university. You can finde the project on Github.

History:

I started to create ILMO for the (rather small) library in the study rooms of mediacal engineering. It contains about 300 books, 120 labcoats and safty glasses and some more stuff. As I was in charge of the lends I started to get annoyed by our paper-based solution. Especially when a bunch of people was trying to lend things it took to much time. Also reminding people to return stuff was unnecessary complicated. Therfore I started to programm this library management tool from scratch. I only reused some basic database and session functions. The project is still a field of learning how to do things for me. Nevertheless after about half a year of development and many tests the system went live in Winter 2018. Since then I fill the bugtracker and slowly improve workflows and add functions.

License

Of course the program is open-source and licensed under GPLv3.

Demo

Right now there is no public available demo but if you are interested I will lead you the way to my test server.

Using ILMO

You know someone who could use somthing like this? I would love to see this software in more libraries. Right now the programm is optimized to the needs of our student union but I would be happy to work more on this.