The application config file is named app.conf and uses the syntax accepted by goconfig, which is similar to Microsoft INI files.

Here’s an example file:



log.trace.output = off
log.info.output  = stderr
log.warn.output  = stderr
log.error.output = stderr


log.trace.output = off
log.info.output  = off
log.warn.output  = %(app.name)s.log
log.error.output = %(app.name)s.log

Each section is a Run Mode. The keys at the top level (not within any section) apply to all run modes. The key under the [prod] section applies only to prod mode. This allows default values to be supplied that apply across all modes, and overridden as required.

New apps start with dev and prod run modes defined, but the user may create any sections they wish. The run mode is chosen at runtime by the argument provided to “revel run” (the command-line tool).

Custom properties

The developer may define custom keys and access them via the revel.Config variable, which exposes a simple api.

Built-in properties

Application settings


The human-readable application name. This is used for some console output and development web pages.


app.name = Booking example application

Default: no value

#### app.secret

The secret key used for cryptographic operations (revel.Sign). Revel also uses it internally to sign session cookies. Setting it to empty string disables signing.

It is set to a random string when initializing a new project (using revel new)


app.secret = pJLzyoiDe17L36mytqC912j81PfTiolHm1veQK6Grn1En3YFdB5lvEHVTwFEaWvj

Default: no value

HTTP settings


The port to listen on.


http.port = 9000

#### http.addr

The IP address on which to listen.

On Linux, empty string indicates a wildcard – on Windows, empty string is silently converted to "localhost"

Default: “”

#### harness.port

Specifies the port for the application to listen on, when run by the harness. For example, when the harness is running, it will listen on http.port, run the application on harness.port, and reverse-proxy requests. Without the harness, the application listens on http.port directly.

By default, a random free port will be chosen. This is only necessary to set when running in an environment that restricts socket access by the program.

Default: 0

#### http.ssl

If true, Revel’s web server will configure itself to accept SSL connections. This requires an X509 certificate and a key file.

Default: false


Specifies the path to an X509 certificate file.

Default: “”


Specifies the path to an X509 certificate key.

Default: “”



Determines whether the template rendering should use chunked encoding. Chunked encoding can decrease the time to first byte on the client side by sending data before the entire template has been fully rendered.

Default: false

#### results.pretty

Configures RenderXml and RenderJson to produce indented XML/JSON. For example:

results.pretty = true

Default: false

Internationalization (i18n)


Specifies the default language for messages when the requested locale is not recognized. If left unspecified, a dummy message is returned to those requests.

For example:

i18n.default_language = en

Default: “”

#### i18n.cookie

Specifies the name of the cookie used to store the user’s locale.

Default: “%(cookie.prefix)_LANG” (see cookie.prefix)


Revel watches your project and supports hot-reload for a number of types of source. To enable watching:

watch = true

If false, nothing will be watched, regardless of the other watch.* configuration keys. (This is appropriate for production deployments)

Default: true

#### watch.templates

If true, Revel will watch your views for changes and reload them as necessary.

Default: true

#### watch.routes

If true, Revel will watch your routes file for changes and reload as necessary.

Default: true

#### watch.code

If true, Revel will watch your Go code for changes and rebuild your application as necessary. (This runs the harness as a reverse-proxy to the application)

All code within the application’s app/ directory (or any sub-directory) is watched.

Default: true


Revel components use the following cookies by default: * REVEL_SESSION * REVEL_LANG * REVEL_FLASH * REVEL_ERRORS


Revel uses this property as the prefix for the Revel-produced cookies. This is so that multiple REVEL applications can coexist on the same host.

For example,

cookie.prefix = MY

would result in the following cookie names: * MY_SESSION * MY_LANG * MY_FLASH * MY_ERRORS

Default: “REVEL”



Revel uses this property to set the expiration of the session cookie. Revel uses ParseDuration to parse the string. The default value is 30 days. It can also be set to “session” to allow session only expiry. Please note that the client behaviour is dependent on browser configuration so the result is not always guaranteed.



Specifies an override for the left and right delimiters used in the templates.
The delimiters must be specified as “LEFT_DELIMS RIGHT_DELIMS”

Default: “{{ }}”



Specifies the default date format for the application. Revel uses this in two places: * Binding dates to a time.Time (see binding) * Printing dates using the date template function (see template funcs)

Default: “2006-01-02”

#### format.datetime

Specifies the default datetime format for the application. Revel uses this in two places: * Binding dates to a time.Time (see binding) * Printing dates using the datetime template function (see template funcs)

Default: “2006-01-02 15:04”



Specifies the import path of the desired database/sql driver for the db module.

Default: “”

#### db.driver

Specifies the name of the database/sql driver (used in sql.Open).

Default: “”

#### db.spec

Specifies the data source name of your database/sql database (used in sql.Open).

Default: “”



Build tags to use when building an application.

Default: “”




The cache module is a simple interface to a heap or distributed cache.


Sets the default duration before cache entries are expired from the cache. It is used when the caller passes the constant cache.DEFAULT.

It is specified as a duration string acceptable to time.ParseDuration

(Presently it is not possible to specify a default of FOREVER)

Default: “1h” (1 hour)

#### cache.memcached

If true, the cache module uses memcached instead of the in-memory cache.

Default: false

#### cache.hosts

A comma-separated list of memcached hosts. Cache entries are automatically sharded among available hosts using a deterministic mapping of cache key to host name. Hosts may be listed multiple times to increase their share of cache space.

Default: “”

Scheduled Jobs

The jobs module allows you to run scheduled or ad-hoc jobs.

Named schedules

Named cron schedules may be configured by setting a key of the form:

cron.schedulename = @hourly

That schedule may then be referenced upon submission to the job runner. For example:

jobs.Schedule("cron.schedulename", job)

#### jobs.pool

The number of jobs allowed to run concurrently. For example:

jobs.pool = 4

If 0, there is no limit imposed.

Default: 10

#### jobs.selfconcurrent

If true, allows a job to run even if previous instances of that job are still in progress.

Default: false


Modules may be added to an application by specifying their base import path. For example:

module.testrunner = github.com/robfig/revel/modules/testrunner

Areas for development

  • Allow inserting command line arguments as config values or otherwise specifying config values from the command line.