Configuration§

Quick Start§

To run an application in Unit, first set up an application object. Let’s store it in a file to PUT it into the config/applications section of Unit’s control API, available via the control socket at http://localhost/:

# cat << EOF > config.json

    > {
    >     "type": "php",
    >     "root": "/www/blogs/scripts"
    > }
    > EOF

# curl -X PUT --data-binary @config.json --unix-socket \
       /path/to/control.unit.sock http://localhost/config/applications/blogs/

    {
            "success": "Reconfiguration done."
    }

Unit starts the application process. Next, reference the application object from a listener object, comprising an IP (or a wildcard to match any IPs) and a port number, in the config/listeners section of the API:

# cat << EOF > config.json

    > {
    >     "pass": "applications/blogs"
    > }
    > EOF

# curl -X PUT --data-binary @config.json --unix-socket \
       /path/to/control.unit.sock http://localhost/config/listeners/127.0.0.1:8300

    {
            "success": "Reconfiguration done."
    }

Unit accepts requests at the specified IP and port, passing them to the application process. Your app works!

Finally, check the resulting configuration:

# curl --unix-socket /path/to/control.unit.sock http://localhost/config/

    {
        "listeners": {
            "127.0.0.1:8300": {
                "pass": "applications/blogs"
            }
        },

        "applications": {
            "blogs": {
                "type": "php",
                "root": "/www/blogs/scripts/"
            }
        }
    }

You can upload the entire configuration at once or update it in portions. For details of configuration techniques, see below. For a full configuration sample, see here.

Configuration Management§

Unit’s configuration is JSON-based, accessed via the control socket, and entirely manageable over HTTP.

Note

Here, we use curl to query Unit’s control API, prefixing URIs with http://localhost as expected by this utility. You can use any tool capable of making HTTP requests; also, the hostname is irrelevant for Unit.

To address parts of the configuration, query the control socket over HTTP; URI path segments of your requests to the API must be names of its JSON object members or indexes of its array elements.

You can manipulate the API with the following HTTP methods:

Method	Action
`GET`	Returns the entity at the request URI as JSON value in the HTTP response body.
`PUT`	Replaces the entity at the request URI and returns status message in the HTTP response body.
`DELETE`	Deletes the entity at the request URI and returns status message in the HTTP response body.

Before a change, Unit evaluates the difference it causes in the entire configuration; if there’s none, nothing is done. For example, you can’t restart an app by uploading the same configuration it already has.

Unit performs actual reconfiguration steps as gracefully as possible: running tasks expire naturally, connections are properly closed, processes end smoothly.

Any type of update can be done with different URIs, provided you supply the right JSON:

# curl -X PUT -d '{ "pass": "applications/blogs" }' --unix-socket \
       /path/to/control.unit.sock http://localhost/config/listeners/127.0.0.1:8300

# curl -X PUT -d '"applications/blogs"' --unix-socket /path/to/control.unit.sock \
       http://localhost/config/listeners/127.0.0.1:8300/pass

However, mind that the first command replaces the entire listener, dropping any other options you could have configured, whereas the second one replaces only the pass value and leaves other options intact.

Examples§

To minimize typos and effort, avoid embedding JSON payload in your commands; instead, consider storing your configuration snippets for review and reuse. Suppose you save your application object as wiki.json:

{
    "type": "python",
    "module": "wsgi",
    "user": "www-wiki",
    "group": "www-wiki",
    "path": "/www/wiki/"
}

Use it to set up an application called wiki-prod:

# curl -X PUT --data-binary @/path/to/wiki.json \
       --unix-socket /path/to/control.unit.sock http://localhost/config/applications/wiki-prod

Use it again to set up a development version of the same app called wiki-dev:

# curl -X PUT --data-binary @/path/to/wiki.json \
       --unix-socket /path/to/control.unit.sock http://localhost/config/applications/wiki-dev

Toggle the wiki-dev app to another source code directory:

# curl -X PUT -d '"/www/wiki-dev/"' \
       --unix-socket /path/to/control.unit.sock http://localhost/config/applications/wiki-dev/path

Next, boost the process count for the production app to warm it up a bit:

# curl -X PUT -d '5' \
       --unix-socket /path/to/control.unit.sock http://localhost/config/applications/wiki-prod/processes

Add a listener for the wiki-prod app to accept requests at all host IPs:

# curl -X PUT -d '{ "pass": "applications/wiki-prod" }' \
       --unix-socket /path/to/control.unit.sock 'http://localhost/config/listeners/*:8400'

Plug the wiki-dev app into the listener to test it:

# curl -X PUT -d '"applications/wiki-dev"' --unix-socket /path/to/control.unit.sock \
       'http://localhost/config/listeners/*:8400/pass'

Then rewire the listener, adding a route to distinguish the apps by the URI:

# cat << EOF > config.json

    > [
    >     {
    >         "match": {
    >             "uri": "/dev/*"
    >         },
    >
    >         "action": {
    >             "pass": "applications/wiki-dev"
    >         }
    >     },
    >     {
    >         "action": {
    >             "pass": "applications/wiki-prod"
    >         }
    >     }
    > ]
    > EOF

# curl -X PUT --data-binary @config.json --unix-socket \
       /path/to/control.unit.sock http://localhost/config/routes

# curl -X PUT -d '"routes"' --unix-socket \
       /path/to/control.unit.sock 'http://localhost/config/listeners/*:8400/pass'

Change the wiki-dev app path prefix in the routes array using its index number:

# curl -X PUT -d '"/development/*"' --unix-socket=/path/to/control.unit.sock \
       http://localhost/config/routes/0/match/uri

To get the complete config section:

# curl --unix-socket /path/to/control.unit.sock http://localhost/config/

    {
        "listeners": {
            "*:8400": {
                "pass": "routes"
            }
        },

        "applications": {
            "wiki-dev": {
                "type": "python",
                "module": "wsgi",
                "user": "www-wiki",
                "group": "www-wiki",
                "path": "/www/wiki-dev/"
            },

            "wiki-prod": {
                "type": "python",
                "processes": 5,
                "module": "wsgi",
                "user": "www-wiki",
                "group": "www-wiki",
                "path": "/www/wiki/"
            }
        },

        "routes": [
            {
                "match": {
                    "uri": "/development/*"
                },

                "action": {
                    "pass": "applications/wiki-dev"
                }
            },
            {
                "action": {
                    "pass": "applications/wiki-prod"
                }
            }
        ]
    }

To obtain the wiki-dev application object:

# curl --unix-socket /path/to/control.unit.sock \
       http://localhost/config/applications/wiki-dev

    {
        "type": "python",
        "module": "wsgi",
        "user": "www-wiki",
        "group": "www-wiki",
        "path": "/www/wiki-dev/"
    }

You can save JSON returned by such requests as .json files for update or review:

# curl --unix-socket /path/to/control.unit.sock \
       http://localhost/config/ > config.json

To drop the listener on *:8400:

# curl -X DELETE --unix-socket /path/to/control.unit.sock \
       'http://localhost/config/listeners/*:8400'

Mind that you can’t delete objects that other objects rely on, such as a route still referenced by a listener:

# curl -X DELETE --unix-socket /var/run/unit/control.sock \
       http://localhost/config/routes

    {
        "error": "Invalid configuration.",
        "detail": "Request \"pass\" points to invalid location \"routes\"."
    }

Listeners§

To start serving HTTP requests with Unit, define a listener in the config/listeners section of the API. A listener uniquely combines a host IP (or a wildcard to match all host IPs) and a port that Unit binds to.

Note

On Linux-based systems, wildcard listeners can’t overlap with other listeners on the same port due to kernel-imposed limitations; for example, *:8080 conflicts with 127.0.0.1:8080.

Unit dispatches the requests it receives to applications or routes referenced by listeners. You can plug several listeners into one app or route, or use a single listener for hot-swapping during testing or staging.

Available options:

Option	Description
`application` (deprecated)	App name: `"application": "qwk2mart"`. Mutually exclusive with `pass`. Warning This option is deprecated. Please update your configurations to use `pass` instead.
`pass` (required)	Qualified app or route name: `"pass": "routes/route66"`, `"pass": "applications/qwk2mart"`. Mutually exclusive with `application`.
`tls`	SSL/TLS configuration object. Its only option, `certificate`, enables secure communication via the listener; it must name a certificate chain that you have configured earlier.

Here, local requests at port 8300 are passed to the blogs app; all requests at 8400 follow the main route:

{
    "127.0.0.1:8300": {
        "pass": "applications/blogs",
        "tls": {
            "certificate": "blogs-cert"
        }
    },

    "*:8400": {
        "pass": "routes/main"
    }
}

Routes§

Unit configuration offers a routes object to enable elaborate internal routing between listeners and apps. Listeners pass requests to routes or directly to apps. Requests are matched against route step conditions; a request fully matching a step’s condition is passed to the app or the route that the step specifies.

In its simplest form, routes can be a single route array:

{
     "listeners": {
         "*:8300": {
             "pass": "routes"
         }
     },

     "routes": [ "simply referred to as routes" ]
}

Another form is an object with one or more named route arrays as members:

{
     "listeners": {
         "*:8300": {
             "pass": "routes/main"
         }
     },

     "routes": {
         "main": [ "named route, qualified name: routes/main" ],
         "route66": [ "named route, qualified name: routes/route66" ]
     }
}

Route Object§

A route array contains step objects as elements; a request passed to a route traverses them sequentially.

Steps have the following options:

Option Description

Option	Description
`match`	Object that defines the step condition. If the request fits the `match` condition, the step’s `pass` is followed. If the request doesn’t match a step, Unit proceeds to the next step of the route. If the request doesn’t match any steps, a 404 “Not Found” response is returned. See below for condition matching details.
`action/pass` (required)	Route’s destination; identical to `pass` in a listener. If you omit `match`, requests are passed unconditionally; to avoid issues, use no more than one such step per route, placing it last.

match

Object that defines the step condition.

If the request fits the match condition, the step’s pass is followed.
If the request doesn’t match a step, Unit proceeds to the next step of the route.
If the request doesn’t match any steps, a 404 “Not Found” response is returned.

See below for condition matching details.

action/pass (required) Route’s destination; identical to pass in a listener. If you omit match, requests are passed unconditionally; to avoid issues, use no more than one such step per route, placing it last.

An example:

{
    "routes": [
        {
            "match": {
                "host": "example.com",
                "uri": "/admin/*"
            },

            "action": {
                "pass": "applications/php5_app"
             }
        },
        {
            "action": {
                "pass": "applications/php7_app"
             }
        }
     ]
}

A more elaborate example with chained routes:

{
    "routes": {
        "main": [
            {
                "match": {
                    "host": [ "www.example.com", "example.com" ]
                },

                "action": {
                    "pass": "routes/site"
                }
            },
            {
                "match": {
                    "host": "blog.example.com"
                },

                "action": {
                    "pass": "applications/blog"
                }
            }
        ],

        "site": [ "..." ]
    }
}

Condition Matching§

The match condition in a step comprises request property names and corresponding patterns:

{
    "match": {
        "request_property1": "pattern",
        "request_property2": ["pattern", "pattern", "..." ]
    },

    "action": {
        "pass": "..."
     }
}

To fit a step’s condition, the request must match all properties listed in it. Available options:

Option	Description
`host`	Request host from the `Host` header field without port number, normalized by removing the trailing period (if any); case-insensitive.
`method`	Request method from the request line; case-insensitive.
`uri`	Request URI path without arguments, normalized by decoding the “%XX” sequences, resolving relative path references (“.” and “..”), and compressing adjacent slashes into one; case-sensitive.

Patterns must be exact matches; they also support wildcards (*) and negations (!):

A wildcard matches zero or more arbitrary characters; pattern can start with it, end with it, or both.
A negation restricts specific patterns; pattern can only start with it.

To be a match against the patterns listed in a condition, the property must meet two requirements:

If there are patterns without negation, at least one of them matches.
No negation-based patterns match.

Note

This type of matching can be explained with set operations. Suppose set U comprises all possible values of a property; set P comprises strings that match any patterns without negation; set N comprises strings that match any negation-based patterns. In this scheme, the matching set will be:

U ∩ P \ N if P ≠ ∅

U \ N if P = ∅

A few examples:

{
    "host": "*.example.com"
}

Only subdomains of example.com will match.

{
    "host": ["*.example.com", "!www.example.com"]
}

Here, any subdomains of example.com will match except www.example.com.

{
    "method": ["!HEAD", "!GET"]
}

Any methods will match except HEAD and GET.

You can also combine special characters in a pattern:

{
    "uri": "!*/api/*"
}

Here, any URIs will match except ones containing /api/.

If all properties match or you omit the condition, Unit routes the request where pass points to:

{
    "match": {
        "host": [ "*.example.com", "!php7.example.com" ],
        "uri": [ "/admin/*", "/store/*" ],
        "method": "POST"
    },

    "action": {
        "pass": "applications/php5_app"
     }
}

Here, all POST requests for URIs prefixed with /admin/ or /store/ within any subdomains of example.com (except php7) are routed to php5_app.

Applications§

Each app that Unit runs is defined as an object in the config/applications section of the control API; it lists the app’s language and settings, its runtime limits, process model, and various language-specific options.

Here, Unit runs 20 processes of a PHP app called blogs, stored in the /www/blogs/scripts/ directory:

{
    "blogs": {
        "type": "php",
        "processes": 20,
        "root": "/www/blogs/scripts/"
    }
}

Each application object has a number of common options that can be specified for any application regardless of its type:

Option	Description
`type` (required)	Type of the application: `external` (Go and Node.js), `java`, `perl`, `php`, `python`, or `ruby`. Except with `external`, you can detail the runtime version: `"type": "python 3"`, `"type": "python 3.4"`, or even `"type": "python 3.4.9rc1"`. Unit searches its modules and uses the latest matching one, reporting an error if none match. For example, if you have installed only one PHP 7 module, 7.1.9, it will match `"php"`, `"php 7"`, `"php 7.1"`, and `"php 7.1.9"`. If you install two PHP modules, 7.0.2 and 7.0.23, and prefer to use 7.0.2, set `"type": "php 7.0.2"`. If you supply `"php 7"`, PHP 7.0.23 will be used as the latest version available.
`limits`	An object that accepts two integer options, `timeout` and `requests`. Their values restrict the life cycle of an application process. For details, see Request Limits.
`processes`	An integer or an object. Integer value configures a static number of application processes. Object accepts dynamic process management options: `max`, `spare`, and `idle_timeout`. For details, see Process Management. The default value is 1.
`working_directory`	Working directory for the application. If not specified, the working directory of Unit daemon is used.
`user`	Username that runs the app process. If not specified, `nobody` is used.
`group`	Group name that runs the app process. If not specified, user’s primary group is used.
`environment`	Environment variables to be used by the application.

Example:

{
    "type": "python 3.6",
    "processes": 16,
    "working_directory": "/www/python-apps",
    "path": "blog",
    "module": "blog.wsgi",
    "user": "blog",
    "group": "blog",
    "limits": {
        "timeout": 10,
        "requests": 1000
    },

    "environment": {
        "DJANGO_SETTINGS_MODULE": "blog.settings.prod",
        "DB_ENGINE": "django.db.backends.postgresql",
        "DB_NAME": "blog",
        "DB_HOST": "127.0.0.1",
        "DB_PORT": "5432"
    }
}

Depending on the type of the application, you may need to configure a number of additional options. In the example above, Python-specific options path and module are used.

Process Management and Limits§

Application process behavior in Unit is described by two configuration options, limits and processes.

Request Limits§

The limits object has two options:

Option Description
timeout Request timeout in seconds. If an application process exceeds this limit while processing a request, Unit terminates the process and returns an HTTP error to the client.
requests Maximum number of requests Unit allows an application process to serve. If this limit is reached, Unit terminates and restarts the application process. This allows to mitigate application memory leaks or other issues that may accumulate over time.

Option	Description
`timeout`	Request timeout in seconds. If an application process exceeds this limit while processing a request, Unit terminates the process and returns an HTTP error to the client.
`requests`	Maximum number of requests Unit allows an application process to serve. If this limit is reached, Unit terminates and restarts the application process. This allows to mitigate application memory leaks or other issues that may accumulate over time.

Process Management§

The processes option offers choice between static and dynamic process management model. If you provide an integer value, Unit immediately launches the given number of application processes and maintains them statically without scaling.

Unit also supports a dynamic prefork model for processes that is enabled and configured with the following parameters:

Option Description

Option	Description
`max`	Maximum number of application processes that Unit will maintain (busy and idle). The default value is 1.
`spare`	Minimum number of idle processes that Unit will reserve for the application when possible. When Unit starts an application, `spare` idle processes are launched. As requests arrive, Unit assigns them to existing idle processes and forks new idle ones to maintain the `spare` level if `max` permits. When processes complete requests and turn idle, Unit terminates extra ones after a timeout. The default value is 0. The value of `spare` cannot exceed `max`.
`idle_timeout`	Number of seconds for Unit to wait before it terminates an extra idle process, when the count of idle processes exceeds `spare`. The default value is 15.

max

Maximum number of application processes that Unit will maintain (busy and idle).

The default value is 1.

spare

Minimum number of idle processes that Unit will reserve for the application when possible. When Unit starts an application, spare idle processes are launched. As requests arrive, Unit assigns them to existing idle processes and forks new idle ones to maintain the spare level if max permits. When processes complete requests and turn idle, Unit terminates extra ones after a timeout.

The default value is 0. The value of spare cannot exceed max.

idle_timeout

Number of seconds for Unit to wait before it terminates an extra idle process, when the count of idle processes exceeds spare.

The default value is 15.

If processes is omitted entirely, Unit creates 1 static process. If an empty object is provided: "processes": {}, dynamic behavior with default parameter values is assumed.

In the following example, Unit tries to keep 5 idle processes, no more than 10 processes in total, and terminates extra idle processes after 20 seconds of inactivity:

{
    "max": 10,
    "spare": 5,
    "idle_timeout": 20
}

Go/Node.js§

To run your Go or Node.js applications in Unit, you need to configure them and modify their source code as suggested below. Let’s start with the application configuration:

Option Description

Option	Description
`executable` (required)	Pathname of the application, absolute or relative to `working_directory`. For Node.js, supply your `.js` pathname and start the file itself with a proper shebang: #!/usr/bin/env node
`arguments`	Command line arguments to be passed to the application. The example below is equivalent to `/www/chat/bin/chat_app --tmp-files /tmp/go-cache`.

executable (required)

Pathname of the application, absolute or relative to working_directory.

For Node.js, supply your .js pathname and start the file itself with a proper shebang:

#!/usr/bin/env node

arguments Command line arguments to be passed to the application. The example below is equivalent to /www/chat/bin/chat_app --tmp-files /tmp/go-cache.

Example:

{
    "type": "external",
    "working_directory": "/www/chat",
    "executable": "bin/chat_app",
    "user": "www-go",
    "group": "www-go",
    "arguments": ["--tmp-files", "/tmp/go-cache"]
}

Before applying the configuration, update the application itself.

Modifying Go Sources§

In the import section, reference the "nginx/unit" package that you have installed earlier:

import (
    ...
    "nginx/unit"
    ...
)

In the main() function, replace the http.ListenandServe call with unit.ListenAndServe:

func main() {
    ...
    http.HandleFunc("/", handler)
    ...
    //http.ListenAndServe(":8080", nil)
    unit.ListenAndServe(":8080", nil)
    ...
}

The resulting application works as follows:

When you run it standalone, the unit.ListenAndServe call falls back to http functionality.
When Unit runs it, unit.ListenAndServe communicates with Unit’s router process directly, ignoring the address supplied as its first argument and relying on the listener’s settings instead.

Modifying Node.js Sources§

First, you need to have the unit-http package installed. If it’s global, symlink it in your project directory:

# npm link unit-http

Do the same if you move a Unit-hosted application to a new system where unit-http is installed globally.

Next, use unit-http instead of http in your code:

var http = require('unit-http');

Java§

Object	Description
`classpath`	Array of paths to your app’s required libraries (may point to directories or `.jar` files).
`options`	Array of strings defining JVM runtime options.
`webapp` (required)	Pathname of the application’s packaged or unpackaged `.war` file.

Example:

{
    "type": "java",
    "classpath": ["/www/qwk2mart/lib/qwk2mart-2.0.0.jar"],
    "options": ["-Dlog_path=/var/log/qwk2mart.log"],
    "webapp": "/www/qwk2mart/qwk2mart.war"
}

Perl§

Option	Description
`script` (required)	PSGI script path.

Example:

{
    "type": "perl",
    "script": "/www/bugtracker/app.psgi",
    "working_directory": "/www/bugtracker",
    "processes": 10,
    "user": "www",
    "group": "www"
}

PHP§

Option	Description
`index`	Filename appended to any URI paths ending with a slash; applies if `script` is omitted. Default value is `index.php`.
`options`	Object that defines `php.ini` location and options. For details, see below.
`root` (required)	Base directory of your PHP app’s file structure. All URI paths are relative to this value.
`script`	Filename of a PHP script; if set, Unit uses this script to serve any requests to this application. Relative to `root`.

The index and script options enable two modes of operation:

If script is set, all requests to the application are handled by the script you provide.
Otherwise, the requests are served according to their URI paths; if script name is omitted, index is used.

You can customize php.ini via the options object:

Option	Description
`file`	Pathname of the `php.ini` file.
`admin`, `user`	Objects with PHP configuration directives. Directives in `admin` are set in `PHP_INI_SYSTEM` mode; it means that your application can’t alter them. Directives in `user` are set in `PHP_INI_USER` mode; your application is allowed to update them in runtime.

Directives from php.ini are applied first; next, admin and user objects are applied.

Note

Provide string values for any directives you specify in options (for example, "max_file_uploads": "64" instead of "max_file_uploads": 64). For flags, use "0" and "1" only. For more information about PHP_INI_* modes, see the PHP documentation.

Example:

{
    "type": "php",
    "processes": 20,
    "root": "/www/blogs/scripts/",
    "user": "www-blogs",
    "group": "www-blogs",

    "options": {
        "file": "/etc/php.ini",
        "admin": {
            "memory_limit": "256M",
            "variables_order": "EGPCS",
            "expose_php": "0"
        },
        "user": {
            "display_errors": "0"
        }
    }
}

Python§

Option	Description
`module` (required)	WSGI module name. To run the app, Unit looks for an `application` callable in the module you supply; the `module` itself is imported just like in Python.
`path`	Additional lookup path for Python modules; this string is inserted into `sys.path`.
`home`	Path to Python virtual environment for the application. You can set this value relative to the `working_directory` of the application. Note The Python version used by Unit to run the application is controlled by the `type` of the application. Unit doesn’t use command line Python interpreter within the virtual environment due to performance considerations.

Example:

{
    "type": "python 3.6",
    "processes": 10,
    "working_directory": "/www/store/",
    "path": "/www/store/cart/",
    "home": "/www/store/.virtualenv/",
    "module": "wsgi",
    "user": "www",
    "group": "www"
}

Ruby§

Option	Description
`script` (required)	Rack script path.

Example:

{
    "type": "ruby",
    "processes": 5,
    "user": "www",
    "group": "www",
    "script": "/www/cms/config.ru"
}

Settings§

Unit has a global settings configuration object that stores instance-wide preferences. Its http option fine-tunes the handling of HTTP requests from the clients:

Option	Description
`header_read_timeout`	Maximum number of seconds to read the header of a client’s request. If Unit doesn’t receive the entire header from the client within this interval, it responds with a 408 Request Timeout error. The default value is 30.
`body_read_timeout`	Maximum number of seconds to read data from the body of a client’s request. It limits the interval between consecutive read operations, not the time to read the entire body. If Unit doesn’t receive any data from the client within this interval, it responds with a 408 Request Timeout error. The default value is 30.
`send_timeout`	Maximum number of seconds to transmit data in the response to a client. It limits the interval between consecutive transmissions, not the entire response transmission. If the client doesn’t receive any data within this interval, Unit closes the connection. The default value is 30.
`idle_timeout`	Maximum number of seconds between requests in a keep-alive connection. If no new requests arrive within this interval, Unit responds with a 408 Request Timeout error and closes the connection. The default value is 180.
`max_body_size`	Maximum number of bytes in the body of a client’s request. If the body size exceeds this value, Unit responds with a 413 Payload Too Large error and closes the connection. The default value is 8388608 (8 MB).

Example:

{
    "settings": {
        "http": {
            "header_read_timeout": 10,
            "body_read_timeout": 10,
            "send_timeout": 10,
            "idle_timeout": 120,
            "max_body_size": 6291456
        }
    }
}

Access Log§

To enable access logging, specify the log file path in the access_log option of the config object.

In the example below, all requests will be logged to /var/log/access.log:

# curl -X PUT -d '"/var/log/access.log"' \
       --unix-socket /path/to/control.unit.sock \
       http://localhost/config/access_log

    {
        "success": "Reconfiguration done."
    }

The log is written in the Combined Log Format. Example of a log line:

127.0.0.1 - - [21/Oct/2015:16:29:00 -0700] "GET / HTTP/1.1" 200 6022 "http://example.com/links.html" "Godzilla/5.0 (X11; Minix i286) Firefox/42"

SSL/TLS and Certificates§

To set up SSL/TLS access for your application, upload a .pem file containing your certificate chain and private key to Unit. Next, reference the uploaded bundle in the listener’s configuration. After that, the listener’s application becomes accessible via SSL/TLS.

First, create a .pem file with your certificate chain and private key:

$ cat cert.pem ca.pem key.pem > bundle.pem

Note

Usually, your website’s certificate (optionally followed by the intermediate CA certificate) is enough to build a certificate chain. If you add more certificates to your chain, order them leaf to root.

Upload the resulting file to Unit’s certificate storage under a suitable name:

# curl -X PUT --data-binary @bundle.pem --unix-socket /path/to/control.unit.sock \
       http://localhost/certificates/<bundle>

    {
        "success": "Certificate chain uploaded."
    }

Warning

Don’t use -d for file upload; this option damages .pem files. Use the --data-binary option when uploading file-based data with curl to avoid data corruption.

Internally, Unit stores uploaded certificate bundles along with other configuration data in its state subdirectory; Unit’s control API maps them to a separate configuration section, aptly named certificates:

{
    "certificates": {
        "<bundle>": {
            "key": "RSA (4096 bits)",
            "chain": [
                {
                    "subject": {
                        "common_name": "example.com",
                        "alt_names": [
                            "example.com",
                            "www.example.com"
                        ],

                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme, Inc."
                    },

                    "issuer": {
                        "common_name": "intermediate.ca.example.com",
                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme Certification Authority"
                    },

                    "validity": {
                        "since": "Sep 18 19:46:19 2018 GMT",
                        "until": "Jun 15 19:46:19 2021 GMT"
                    }
                },

                {
                    "subject": {
                        "common_name": "intermediate.ca.example.com",
                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme Certification Authority"
                    },

                    "issuer": {
                        "common_name": "root.ca.example.com",
                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme Root Certification Authority"
                    },

                    "validity": {
                        "since": "Feb 22 22:45:55 2016 GMT",
                        "until": "Feb 21 22:45:55 2019 GMT"
                    }
                },
            ]
        }
    }
}

Note

You can access individual certificates in your chain, as well as specific alternative names, by their indexes:

# curl -X GET --unix-socket /path/to/control.unit.sock \
       http://localhost/certificates/<bundle>/chain/0/
# curl -X GET --unix-socket /path/to/control.unit.sock \
       http://localhost/certificates/<bundle>/chain/0/subject/alt_names/0/

Next, add a tls object to your listener configuration, referencing the uploaded bundle’s name in certificate:

{
    "listeners": {
        "127.0.0.1:8080": {
            "pass": "applications/wsgi-app",
            "tls": {
                "certificate": "<bundle>"
            }
        }
    }
}

The resulting control API configuration may look like this:

{
    "certificates": {
        "<bundle>": {
            "key": "<key type>",
            "chain": ["<certificate chain, omitted for brevity>"]
        }
    },

    "config": {
        "listeners": {
            "127.0.0.1:8080": {
                "pass": "applications/wsgi-app",
                "tls": {
                    "certificate": "<bundle>"
                }
            }
        },

        "applications": {
            "wsgi-app": {
                "type": "python",
                "module": "wsgi",
                "path": "/usr/www/wsgi-app/"
            }
        }
    }
}

Now you’re solid. The application is accessible via SSL/TLS:

$ curl -v https://127.0.0.1:8080
    ...
    * TLSv1.2 (OUT), TLS handshake, Client hello (1):
    * TLSv1.2 (IN), TLS handshake, Server hello (2):
    * TLSv1.2 (IN), TLS handshake, Certificate (11):
    * TLSv1.2 (IN), TLS handshake, Server finished (14):
    * TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
    * TLSv1.2 (OUT), TLS change cipher, Client hello (1):
    * TLSv1.2 (OUT), TLS handshake, Finished (20):
    * TLSv1.2 (IN), TLS change cipher, Client hello (1):
    * TLSv1.2 (IN), TLS handshake, Finished (20):
    * SSL connection using TLSv1.2 / AES256-GCM-SHA384
    ...

Finally, you can DELETE a certificate bundle that you don’t need anymore from the storage:

# curl -X DELETE --unix-socket /path/to/control.unit.sock \
       http://localhost/certificates/<bundle>

    {
        "success": "Certificate deleted."
    }

Note

You can’t delete certificate bundles still referenced in your configuration, overwrite existing bundles using PUT, or (obviously) delete non-existent ones.

Happy SSLing!

Full Example§

{
    "certificates": {
        "bundle": {
            "key": "RSA (4096 bits)",
            "chain": [
                {
                    "subject": {
                        "common_name": "example.com",
                        "alt_names": [
                            "example.com",
                            "www.example.com"
                        ],

                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme, Inc."
                    },

                    "issuer": {
                        "common_name": "intermediate.ca.example.com",
                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme Certification Authority"
                    },

                    "validity": {
                        "since": "Sep 18 19:46:19 2018 GMT",
                        "until": "Jun 15 19:46:19 2021 GMT"
                    }
                },

                {
                    "subject": {
                        "common_name": "intermediate.ca.example.com",
                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme Certification Authority"
                    },

                    "issuer": {
                        "common_name": "root.ca.example.com",
                        "country": "US",
                        "state_or_province": "CA",
                        "organization": "Acme Root Certification Authority"
                    },

                    "validity": {
                        "since": "Feb 22 22:45:55 2016 GMT",
                        "until": "Feb 21 22:45:55 2019 GMT"
                    }
                }
            ]
        }
    },

    "config": {
        "settings": {
            "http": {
                "header_read_timeout": 10,
                "body_read_timeout": 10,
                "send_timeout": 10,
                "idle_timeout": 120,
                "max_body_size": 6291456
            }
        },

        "listeners": {
            "*:8300": {
                "pass": "applications/blogs",
                "tls": {
                    "certificate": "bundle"
                }
            },

            "*:8400": {
                "pass": "applications/wiki"
            },

            "*:8500": {
                "pass": "applications/go_chat_app"
            },

            "127.0.0.1:8600": {
                "pass": "applications/bugtracker"
            },

            "127.0.0.1:8601": {
                "pass": "routes/cms"
            },

            "*:8700": {
                "pass": "applications/qwk2mart"
            }
        },

        "routes" {
            "cms": [
                {
                    "match": {
                        "uri": "!/admin/*"
                    },
                    "action": {
                        "pass": "applications/cms_main"
                    }
                },

                {
                    "action": {
                        "pass": "applications/cms_admin"
                    }
                }
            ]
        },

        "applications": {
            "blogs": {
                "type": "php",
                "processes": 20,
                "root": "/www/blogs/scripts/",
                "limits": {
                    "timeout": 10,
                    "requests": 1000
                },

                "options": {
                    "file": "/etc/php.ini",
                    "admin": {
                        "memory_limit": "256M",
                        "variables_order": "EGPCS",
                        "expose_php": "0"
                    },

                    "user": {
                        "display_errors": "0"
                    }
                }
            },

            "wiki": {
                "type": "python",
                "processes": 10,
                "path": "/www/wiki",
                "module": "wsgi",
                "environment": {
                    "DJANGO_SETTINGS_MODULE": "blog.settings.prod",
                    "DB_ENGINE": "django.db.backends.postgresql",
                    "DB_NAME": "blog",
                    "DB_HOST": "127.0.0.1",
                    "DB_PORT": "5432"
                }
            },

            "go_chat_app": {
                "type": "external",
                "user": "www-chat",
                "group": "www-chat",
                "working_directory": "/www/chat",
                "executable": "bin/chat_app"
            },

            "bugtracker": {
                "type": "perl",
                "processes": {
                    "max": 10,
                    "spare": 5,
                    "idle_timeout": 20
                },

                "working_directory": "/www/bugtracker",
                "script": "app.psgi"
            },

            "cms_main": {
                "type": "ruby",
                "processes": 5,
                "script": "/www/cms/main.ru"
            },

            "cms_admin": {
                "type": "ruby",
                "processes": 1,
                "script": "/www/cms/admin.ru"
            },

            "qwk2mart": {
                "type": "java",
                "classpath": ["/www/qwk2mart/lib/qwk2mart-2.0.0.jar"],
                "options": ["-Dlog_path=/var/log/qwk2mart.log"],
                "webapp": "/www/qwk2mart/qwk2mart.war"
            }
        },

        "access_log": "/var/log/access.log"
    }
}