Create Users

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$ sudo adduser --system --shell /bin/bash --gecos 'Git Version Control' --group --disabled-password --home /home/git git
$ sudo adduser --system --shell /bin/bash --gecos 'Woodpecker CI' --group --disabled-password --home /home/woodpecker woodpecker

Binaries

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$ wget https://dl.gitea.com/gitea/1.19.0/gitea-1.19.0-linux-amd64
$ sudo mv gitea-1.19.0-linux-amd64 /usr/local/bin/gitea
$ sudo chmod +x /usr/local/bin/gitea
$ wget https://github.com/woodpecker-ci/woodpecker/releases/download/v0.15.7/woodpecker-agent_0.15.7_amd64.deb
$ wget https://github.com/woodpecker-ci/woodpecker/releases/download/v0.15.7/woodpecker-cli_0.15.7_amd64.deb
$ wget https://github.com/woodpecker-ci/woodpecker/releases/download/v0.15.7/woodpecker-server_0.15.7_amd64.deb
$ sudo apt-get install ./woodpecker-*

Directories

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$ sudo mkdir -p /var/lib/gitea/{custom,data,log}
$ sudo chown -R git:git /var/lib/gitea/
$ sudo chmod -R 750 /var/lib/gitea/
$ sudo mkdir /etc/gitea
$ sudo chown root:git /etc/gitea
$ sudo chmod 770 /etc/gitea
$ sudo mkdir -p /var/lib/woodpecker
$ sudo chown -R woodpecker:woodpecker /var/lib/woodpecker
$ sudo chmod -R 750 /var/lib/woodpecker/
$ sudo touch /etc/woodpecker.conf
$ sudo chmod 770 /etc/woodpecker.conf

Setup

Database

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$ sudo apt-get install postgresql postgresql-contrib
$ sudo -u postgres psql
postgres=# create database git;
postgres=# create user git with encrypted password 'pass';
postgres=# grant all privileges on database git to git;
postgres=# create database woodpecker;
postgres=# create user woodpecker with encrypted password 'pass';
postgres=# grant all privileges on database woodpecker to woodpecker;
postgres=# exit

nginx

Save the following as sudo vim /etc/nginx/sites-available/gitea.conf

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server {
    listen 80;
    server_name git.YOUR_DOMAIN.com;

    location / {
        proxy_pass http://localhost:3000;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Connection "";
        chunked_transfer_encoding off;
        proxy_buffering off;
    }
}

Save the following as sudo vim /etc/nginx/sites-available/woodpecker.conf

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server {
    listen 80;
    server_name woodpecker.YOUR_DOMAIN.com;

    location / {
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_set_header Host $http_host;

        proxy_pass http://127.0.0.1:8000;
        proxy_redirect off;
        proxy_http_version 1.1;
        proxy_set_header Connection "";
        proxy_buffering off;

        chunked_transfer_encoding off;
    }
}

enable both of these configs

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sudo ln -s /etc/nginx/sites-available/gitea.conf /etc/nginx/sites-enabled/
sudo ln -s /etc/nginx/sites-available/woodpecker.conf /etc/nginx/sites-enabled/

Restart nginx service

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sudo systemctl restart nginx

System Services

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$ sudo wget https://raw.githubusercontent.com/go-gitea/gitea/main/contrib/systemd/gitea.service -P /etc/systemd/system/

Open /etc/systemd/system/gitea.service and uncoment postgresql lines.

Start the service

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$ sudo systemctl start gitea

open http://IP_ADDRESS:3000 and configure the database settings.

Open /etc/gitea/app.ini and and change ROOT_URL to git.YOUR_DOMAIN.com.

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$ sudo systemctl restart gitea

Now visit http://git.YOUR_DOMAIN.com/admin/applications.

Add Woodpecker application with Redirect URI http://woodpecker.YOUR_DOMAIN.com/authorize and copy the client id and the secret somewhere as we will need then in next steps.

Create file /etc/systemd/system/woodpecker.service and paste the following

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[Unit]
Description=Woodpecker
Documentation=https://woodpecker-ci.org/docs/intro
Requires=network-online.target
After=network-online.target

[Service]
User=woodpecker
Group=woodpecker
EnvironmentFile=/etc/woodpecker.conf
ExecStart=/usr/local/bin/woodpecker-server
RestartSec=5
Restart=on-failure
SyslogIdentifier=woodpecker-server
WorkingDirectory=/var/lib/woodpecker

[Install]
WantedBy=multi-user.target

Write the following configuration in /etc/woodpecker.conf

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WOODPECKER_OPEN=true
WOODPECKER_HOST=http://woodpecker.YOUR_DOMAIN.com
WOODPECKER_GITEA=true
WOODPECKER_GITEA_URL=http://git.YOUR_DOMAIN.com
WOODPECKER_GITEA_CLIENT=COPIED_CLIENT_ID
WOODPECKER_GITEA_SECRET=COPIED_SECRET
WOODPECKER_GITEA_SKIP_VERIFY=true
WOODPECKER_DATABASE_DRIVER=postgres
WOODPECKER_DATABASE_DATASOURCE=postgres://woodpecker:password@127.0.0.1:5432/woodpecker?sslmode=disable
GODEBUG=netdns=go

The last environment variable is added because there is a bug and that seting that seems to be an workaround. Start woodpecker service.

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$ sudo systemctl start woodpecker

Now visit http://woodpecker.YOUR_DOMAIN.com. it should redirect you to http://git.YOUR_DOMAIN.com for authentication. Ideally it should be done by now. But the problem is it will crash due to this issue. The workaround is to change WOODPECKER_GITEA_URL to http://woodpecker.YOUR_DOMAIN.com:3000. For some reason, woodpecker server crashes when gitea is behind nginx proxy.

If woodpecker crashes then do the following to get the backtrace

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$ sudo -i # set -o allexport # source /etc/woodpecker.conf # set +o allexport # /usr/local/bin/woodpecker-server

Now if the woodpecker server is working then we can proceed further.
We need to change the gitea port because woodpecker-agent listens to 3000 which will already be in use by gitea.
So, open /etc/gitea/app.ini and change the HTTP_PORT to 4000.
Open the nginx configuration file /etc/nginx/sites-enabled/gitea.conf and change 3000 to 4000.
Now restart both services and check whether everything is working by opening git.YOUR_DOMAIN.com.

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$ sudo systemctl restart gitea
$ sudo systemctl restart nginx

Install docker if you don’t have it installed already.

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sudo apt-get install docker docker-compose

Generate a secret using openssl rand -hex 32 and copy that generated secret into /etc/woodpecker.conf as shown below.

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...
WOODPECKER_AGENT_SECRET=COPIED_SECRET

Then save the following file as /etc/systemd/system/woodpecker-agent.service

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[Unit]
Description=Woodpecker
Documentation=https://woodpecker-ci.org/docs/intro
Requires=network-online.target
After=network-online.target

[Service]
User=woodpecker
Group=woodpecker
EnvironmentFile=/etc/woodpecker-agent.conf
ExecStart=/usr/local/bin/woodpecker-agent
RestartSec=5
Restart=on-failure
SyslogIdentifier=woodpecker-agent
WorkingDirectory=/var/lib/woodpecker

[Install]
WantedBy=multi-user.target

Following is the configuration file /etc/woodpecker-agent.conf

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WOODPECKER_SERVER=localhost:9000
WOODPECKER_BACKEND=docker
WOODPECKER_AGENT_SECRET=COPIED_SECRET

Now start the woodpecker-agent service and check it’s status

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$ sudo systemctl start woodpecker-agent
$ sudo systemctl status woodpecker-agent

For my case I got some errors

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Mar 27 15:39:01 git systemd[1]: Started Woodpecker.
Mar 27 15:39:01 git woodpecker-agent[19259]: {"level":"error","error":"rpc error: code = Unknown desc = invalid agent token","time":"2023-03-27T15:39:01Z","message":"grpc error: done(): code: Unk>
Mar 27 15:39:01 git woodpecker-agent[19259]: {"level":"error","error":"rpc error: code = Unknown desc = invalid agent token","time":"2023-03-27T15:39:01Z","message":"pipeline done with error"}
Mar 27 15:39:01 git systemd[1]: woodpecker-agent.service: Deactivated successfully.

Which implies that the woodpecker-server needs to be restarted. So restart that and restart woodpecker-agent too. Now it should be running.

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$ sudo systemctl restart woodpecker
$ sudo systemctl restart woodpecker-agent
$ sudo systemctl status woodpecker-agent
● woodpecker-agent.service - Woodpecker
     Loaded: loaded (/etc/systemd/system/woodpecker-agent.service; disabled; vendor preset: enabled)
     Active: active (running) since Mon 2023-03-27 15:41:01 UTC; 2s ago
       Docs: https://woodpecker-ci.org/docs/intro
   Main PID: 19344 (woodpecker-agen)
      Tasks: 8 (limit: 4660)
     Memory: 3.6M
        CPU: 21ms
     CGroup: /system.slice/woodpecker-agent.service
             └─19344 /usr/local/bin/woodpecker-agent

Mar 27 15:41:01 git systemd[1]: Started Woodpecker.

I often need to check for inconsistent capitalization in my tex files. So listing all the consecutive capitalized words and characters helps me to decide which one is intentional capitalization and which one is not. The following bash script has two functions can lists all terms (Capitalized Phrase) and acronyms used throughout the input file.

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$ terms filename.tex 
     19 Cloud Station
      9 Sensor Gateway
      7 Sensor Cloud Infrastructure
      ...
$ acronyms filename.tex      
     34 VM
     13 IaaS
     13 CPU
     ...

Rumal is a C++ library that can generate HTML/CSS/Javascript code from significantly identical C++ syntax.
Currently it uses std::string which is supposed to be replaced with compile time strings. Injecting placeholders, is also planned but not yet implemented.
This will make it usable as a template engine.

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std::cout << 
    div(_id(42) / _class("test"),
        span(_id(43) / _class("test"), "Hello"),
        span("World")
    );

I am working on Tash which is an Open Source C++ library for ArangoDB Database which includes APIs for HTTP based document access and a query builder for AQL (Arango Query Language). These are a few example usages.

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std::string name = "Hijibijbij";
tash::shell shell("school"); 
shell <<  select("s").in("students")  
        / filter((clause("s.name") == name) && (clause("s.fathers_name") == name)) 
        / sort().asc("s._key")
        / yield("s"); 
nlohmann::json result;
shell >> result;

The above generates an equivalent AQL and execute it over the arangodb connection