Swarm Template

The daemon swarm-template queries a Docker Swarm API and updates any number of specified templates on the file system. swarm-template can optionally run arbitrary commands when the update process completes.

Installation

You can download a released swarm-template artifact from the Swarm Template release page. If you wish to compile from source, please see the instructions in the Contributing section.

Usage

Command Line

The CLI interface supports all of the options detailed above.

Help

# ./swarm-template -h

Usage: swarm-template [options]

Generate files from docker swarm api

Options:
  -cmd restart xyz
        run command after template is regenerated (e.g restart xyz) (default "true")
  -host string
        swarm manager address. (default "unix:///var/run/docker.sock")
  -interval int
        notify command interval (secs) (default 1)
  -target_file string
        path to a write the template. (default "example/template.cfg")
  -template_file string
        path to a template to generate (default "example/template.tmpl")
  -version
        show version
For more information, see https://github.com/zekiunal/swarm-template

Run

$ ./swarm-template \
    -host="tcp://0.0.0.0:2375"
    -template_file="example/template.tmpl" \
    -target_file="example/target_file" \
    -cmd="/usr/sbin/nginx -s reload" \

Example

1 - Create example services

docker service rm api-example-com_v1-000 api-example-com_v1-001 anotherapi-example-com_v1-0000 anotherapi-example-com_v1-0001 anotherapi-example-com_v1-0002 logs-example-com static-example-com www-example-com

docker service create --name www-example-com --label st.tags="backend,development,public" --label st.version="1.000" --label st.group=www.example.com alpine ping docker.com

docker service create --name static-example-com --label st.tags="static,development,public" --label st.version="1.000" --label st.group=static.example.com alpine ping docker.com   
 
docker service create --name logs-example-com --label st.tags="backend,development,internal" --label st.version="1.000" --label st.group=logs.example.com alpine ping docker.com

docker service create --name api-example-com_v1-000 --label st.tags="backend,development,public,internal,api" --label st.version="1.000" --label st.group=api.example.com  alpine ping docker.com
                        
docker service create --name api-example-com_v1-001 --label st.tags="backend,development,public,internal,api" --label st.version="1.001" --label st.group=api.example.com alpine ping docker.com
 
docker service create --name anotherapi-example-com_v1-0000 --label st.tags="backend,development,public,internal,api" --label st.version="1.000" --label st.group=anotherapi.example.com alpine ping docker.com
                        
docker service create --name anotherapi-example-com_v1-0001 --label st.tags="backend,development,public,internal,api" --label st.version="1.001" --label st.group=anotherapi.example.com alpine ping docker.com

docker service create --name anotherapi-example-com_v1-0002 --label st.tags="backend,development,public,internal,api" --label st.version="1.002" --label st.group=anotherapi.example.com alpine ping docker.com

2 - Run swarm-template

go get -d -v -t && go build -v  && ./swarm-template -template_file="example/template.tmpl" -target_file="example/nginx.conf"

Results

# ./swarm-template -template_file="example/template.tmpl" -target_file="example/nginx.conf"
_/zeki/swarm-template
2016/12/20 12:20:47 Starting Swarm Template
2016/12/20 12:20:47 Added   : api-example-com_v1-001
2016/12/20 12:20:47 Added   : www-example-com
2016/12/20 12:20:47 Added   : anotherapi-example-com_v1-0000
2016/12/20 12:20:47 Added   : anotherapi-example-com_v1-0001
2016/12/20 12:20:47 Added   : anotherapi-example-com_v1-0002
2016/12/20 12:20:47 Added   : logs-example-com
2016/12/20 12:20:47 Added   : api-example-com_v1-000
2016/12/20 12:20:47 Added   : static-example-com

template file

{{ define "main" }}
########################################################################################################################
# List Backend UpStreams
########################################################################################################################
{{ range $service := . }}{{$service_name:=.Name}}{{ range $label := .Labels }}{{ if and ( . | contains "backend") ( . | contains "development") }}
upstream {{$service_name}} {
    server {{$service_name}}:9000 weight=100 max_fails=5000 fail_timeout=5;
}{{ end }}{{ end }}{{ end }}

########################################################################################################################
# List External Services
########################################################################################################################
{{$services := .}}{{ range group . }}{{$service_name:=.Name}}{{$domain := index .Labels "st.group"}}{{ range $label := .Labels }}{{ if and ( . | contains "backend") ( . | contains "development") }}
server {
    listen 80;
    server_name {{$domain}};
    ..
    ...

    location @rewrite3 {
        rewrite ^({{ range keyBy $services $domain}}/v{{index .Labels "st.version"}}|{{end}})/(.*)$ $1/index.php?_url=/$2;
    }
    {{ range keyBy $services $domain}}{{$version := index .Labels "st.version"}}
    location /v{{$version}} {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v{{$version}}(.+\.php)$ {
            fastcgi_pass {{$service_name}};
            ..
            ...
            fastcgi_param VERSION v{{$version}};
        }
    }{{end}}
}{{ end }}{{end}}{{end}}
########################################################################################################################
# List Internal Setup
########################################################################################################################
server {
    listen       80  default_server;
    server_name  _;
    ..
    ...

    location @rewrite2 {
        rewrite ^({{ range $service := . }}{{$service_name:=.Name}}{{ range $label := .Labels }}{{ if and ( . | contains "development") ( . | contains "backend") ( . | contains "internal") }}{{$service_parse := $service_name | split "_"}}{{range $key, $value := $service_parse}}{{if eq $key 1}}{{$value_v := $value | replaceAll "-" "."}}/{{$value_v}}{{else}}/{{$value}}{{end}}{{end}}|{{end}}{{end}}{{end}})/(.*)$ $1/index.php?_url=/$2;
    }
    {{ range $service := . }}{{$service_name:=.Name}}{{ range $label := .Labels }}{{ if and ( . | contains "development") ( . | contains "backend") ( . | contains "internal") }}{{$service_parse := $service_name | split "_"}}
    location {{range $key, $value := $service_parse}}{{if eq $key 1}}{{$value_v := $value | replaceAll "-" "."}}/{{$value_v}}{{else}}/{{$value}}{{end}}{{end}} {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^{{$service_parse := $service_name | split "_"}}{{range $key, $value := $service_parse}}{{if eq $key 1}}{{$value_v := $value | replaceAll "-" "."}}/{{$value_v}}{{else}}/{{$value}}{{end}}{{end}}(.+\.php)$ {
            fastcgi_pass {{$service_name}};
            ..
            ...
            fastcgi_param VERSION {{$service_parse := $service_name | split "_"}}{{range $key, $value := $service_parse}}{{if eq $key 1}}{{$value_v := $value | replaceAll "-" "."}}{{$value_v}}{{end}}{{end}};
        }
    }{{end}}{{end}}{{end}}
}
{{end}}

generated target file

########################################################################################################################
# List Backend UpStreams
########################################################################################################################
upstream anotherapi-example-com_v1-0000 {
    server anotherapi-example-com_v1-0000:9000 weight=100 max_fails=5000 fail_timeout=5;
}
upstream api-example-com_v1-001 {
    server api-example-com_v1-001:9000 weight=100 max_fails=5000 fail_timeout=5;
}
upstream www-example-com {
    server www-example-com:9000 weight=100 max_fails=5000 fail_timeout=5;
}
upstream api-example-com_v1-000 {
    server api-example-com_v1-000:9000 weight=100 max_fails=5000 fail_timeout=5;
}
upstream logs-example-com {
    server logs-example-com:9000 weight=100 max_fails=5000 fail_timeout=5;
}
upstream anotherapi-example-com_v1-0001 {
    server anotherapi-example-com_v1-0001:9000 weight=100 max_fails=5000 fail_timeout=5;
}
upstream anotherapi-example-com_v1-0002 {
    server anotherapi-example-com_v1-0002:9000 weight=100 max_fails=5000 fail_timeout=5;
}

########################################################################################################################
# List External Services
########################################################################################################################
server {
    listen 80;
    server_name anotherapi.example.com;
    ..
    ...

    location @rewrite3 {
        rewrite ^(/v1.000|/v1.001|/v1.002|)/(.*)$ $1/index.php?_url=/$2;
    }
    
    location /v1.000 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.000(.+\.php)$ {
            fastcgi_pass anotherapi-example-com_v1-0000;
            ..
            ...
            fastcgi_param VERSION v1.000;
        }
    }
    location /v1.001 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.001(.+\.php)$ {
            fastcgi_pass anotherapi-example-com_v1-0000;
            ..
            ...
            fastcgi_param VERSION v1.001;
        }
    }
    location /v1.002 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.002(.+\.php)$ {
            fastcgi_pass anotherapi-example-com_v1-0000;
            ..
            ...
            fastcgi_param VERSION v1.002;
        }
    }
}

server {
    listen 80;
    server_name api.example.com;
    ..
    ...

    location @rewrite3 {
        rewrite ^(/v1.001|/v1.000|)/(.*)$ $1/index.php?_url=/$2;
    }
    
    location /v1.001 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.001(.+\.php)$ {
            fastcgi_pass api-example-com_v1-001;
            ..
            ...
            fastcgi_param VERSION v1.001;
        }
    }
    location /v1.000 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.000(.+\.php)$ {
            fastcgi_pass api-example-com_v1-001;
            ..
            ...
            fastcgi_param VERSION v1.000;
        }
    }
}

server {
    listen 80;
    server_name www.example.com;
    ..
    ...

    location @rewrite3 {
        rewrite ^(/v1.000|)/(.*)$ $1/index.php?_url=/$2;
    }
    
    location /v1.000 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.000(.+\.php)$ {
            fastcgi_pass www-example-com;
            ..
            ...
            fastcgi_param VERSION v1.000;
        }
    }
}

server {
    listen 80;
    server_name logs.example.com;
    ..
    ...

    location @rewrite3 {
        rewrite ^(/v1.000|)/(.*)$ $1/index.php?_url=/$2;
    }
    
    location /v1.000 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite3;
        location ~ ^/v1.000(.+\.php)$ {
            fastcgi_pass logs-example-com;
            ..
            ...
            fastcgi_param VERSION v1.000;
        }
    }
}
########################################################################################################################
# List Internal Setup
########################################################################################################################
server {
    listen       80  default_server;
    server_name  _;
    ..
    ...

    location @rewrite2 {
        rewrite ^(/anotherapi-example-com/v1.0000|/api-example-com/v1.001|/api-example-com/v1.000|/logs-example-com|/anotherapi-example-com/v1.0001|/anotherapi-example-com/v1.0002|)/(.*)$ $1/index.php?_url=/$2;
    }
    
    location /anotherapi-example-com/v1.0000 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^/anotherapi-example-com/v1.0000(.+\.php)$ {
            fastcgi_pass anotherapi-example-com_v1-0000;
            ..
            ...
            fastcgi_param VERSION v1.0000;
        }
    }
    location /api-example-com/v1.001 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^/api-example-com/v1.001(.+\.php)$ {
            fastcgi_pass api-example-com_v1-001;
            ..
            ...
            fastcgi_param VERSION v1.001;
        }
    }
    location /api-example-com/v1.000 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^/api-example-com/v1.000(.+\.php)$ {
            fastcgi_pass api-example-com_v1-000;
            ..
            ...
            fastcgi_param VERSION v1.000;
        }
    }
    location /logs-example-com {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^/logs-example-com(.+\.php)$ {
            fastcgi_pass logs-example-com;
            ..
            ...
            fastcgi_param VERSION ;
        }
    }
    location /anotherapi-example-com/v1.0001 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^/anotherapi-example-com/v1.0001(.+\.php)$ {
            fastcgi_pass anotherapi-example-com_v1-0001;
            ..
            ...
            fastcgi_param VERSION v1.0001;
        }
    }
    location /anotherapi-example-com/v1.0002 {
        root /www/http/public/;
        try_files $uri $uri/ @rewrite2;
        location ~ ^/anotherapi-example-com/v1.0002(.+\.php)$ {
            fastcgi_pass anotherapi-example-com_v1-0002;
            ..
            ...
            fastcgi_param VERSION v1.0002;
        }
    }
}

Templating Language

Swarm Template consumes template files in the [Go Template][] format.

Additional Functions

`env`

Wrapper for os.Getenv. Retrieves the value of the environment variable named by the key. It returns the value, which will be empty if the variable is not present. Optionally, you can give a default value that will be returned if the key is not present.

{{env "HOSTNAME" "127.0.0.1"}}

`group`

Query Swarm API for all services in the group by "st.group" label. Services are queried using the following syntax:

{{ range group . }}
    # ...
{{ end}}

`KeyBy`

Creates a map that groups services by tag

{{$services := . }}

{{ range keyBy $services "example_value"}}
    # ...
{{end}}

`contains`

Determines if a needle is within an iterable element.

{{ range .Labels }}
    {{ if and ( . | contains "backend") ( . | contains "production") }}
        # ...
    {{ end }}
{{ end }}

`replaceAll`

Takes the argument as a string and replaces all occurrences of the given string with the given string.

{{"foo.bar" | replaceAll "." "_"}}

This function can be chained with other functions as well:

{{$variable := .Example | replaceAll "-" "."}}

`split`

Splits the given string on the provided separator:

{{"application_version" | split "_"}}

Contributing

Build

docker run --rm --name go-build -v "$PWD":"/go/src/swarm-template" -w "/go/src/swarm-template"  golang sh -c " go get; go build -v"

Alpine

docker run --rm -v "$PWD":"/go/src/swarm-template" -w "/go/src/swarm-template" golang:alpine sh -c "apk add --update git && go get -v; go build -v" && tar -zcvf swarm-template.tar.gz $PWD/swarm-template

If you want to contribute to our project, please follow these guidelines:

Fork the repo
Choose the correct branch to base your contribution (see details bellow)
Implement and test your code
Submit a pull request

ToDo

-cmd options multi command support

Thank You

AzMesai Group Members

Name		Name	Last commit message	Last commit date
Latest commit History 24 Commits
example		example
.gitignore		.gitignore
LICENSE		LICENSE
README.md		README.md
main.go		main.go
service.go		service.go
template.go		template.go

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Repository files navigation

Swarm Template

Installation

Usage

Command Line

Help

Run

Example

1 - Create example services

2 - Run swarm-template

Results

template file

generated target file

Templating Language

Additional Functions

`env`

`group`

`KeyBy`

`contains`

`replaceAll`

`split`

Contributing

Build

Alpine

ToDo

Thank You

About

Releases 7

Packages

Languages

License

zekiunal/swarm-template

Folders and files

Latest commit

History

Repository files navigation

Swarm Template

Installation

Usage

Command Line

Help

Run

Example

1 - Create example services

2 - Run swarm-template

Results

template file

generated target file

Templating Language

Additional Functions

env

group

KeyBy

contains

replaceAll

split

Contributing

Build

Alpine

ToDo

Thank You

About

Topics

Resources

License

Stars

Watchers

Forks

Releases 7

Packages 0

Languages

`env`

`group`

`KeyBy`

`contains`

`replaceAll`

`split`

Packages