grails --helpGrails --help Syntax
Purpose
The --help syntax in Grails is used to request command-line help and detailed information about specific Grails commands.
Examples
Here are some usage examples of the --help syntax in Grails:
-
Display general Grails command line help:
-
Get help for a specific Grails command, such as
create-app:grails create-app --help -
Request assistance for the
generate-controllercommand:grails generate-controller --help
Description
The --help syntax in Grails is a powerful tool for obtaining comprehensive information about Grails commands and their usage. It allows users to understand how to execute specific commands effectively and provides details about available options, arguments, and usage examples.
When you execute grails --help, you will receive a summary of Grails CLI capabilities, including application generation commands, global options, and a list of available commands. This output is designed to help users get started and navigate the Grails CLI effectively.
Usage:
To use the --help syntax, simply append it to a Grails command, as shown in the examples above. This triggers the display of detailed help and information related to the specified command.
grails> --help
Usage: grails [-hvVx] [COMMAND]
Grails CLI command line interface for generating projects and services.
Application generation commands are:
* create-app NAME
* create-webapp NAME
* create-restapi NAME
* create-plugin NAME
* create-webplugin NAME
Options:
-h, --help Show this help message and exit.
-v, --verbose Create verbose output.
-V, --version Print version information and exit.
-x, --stacktrace Show full stack trace when exceptions occur.
Commands:
create-app Creates an application
create-webapp Creates an application
create-plugin Creates an Grails Plugin
create-web-plugin Creates an Grails Web Plugin
create-restapi Creates an REST APIBy using the --help syntax with specific command names, Grails developers can access in-depth documentation, making it easier to work with Grails commands and ensuring they are used correctly in their projects. Here is an example of using --help with the grails create-app command:
grails> create-app --help
Usage: grails create-app [-hivVx] [--list-features] [-g=GORM Implementation] [--jdk=<javaVersion>]
[-s=Servlet Implementation] [-t=TEST] [-f=FEATURE[,FEATURE...]]... [NAME]
Creates an application
[NAME] The name of the application to create.
-f, --features=FEATURE[,FEATURE...]
The features to use. Possible values: h2, scaffolding, gorm-hibernate5,
spring-boot-starter-jetty, springloaded, spring-boot-starter-tomcat,
micronaut-http-client, cache-ehcache, hibernate-validator, postgres,
mysql, cache, database-migration, grails-gsp, hamcrest, gorm-mongodb,
assertj, mockito, spring-boot-starter-undertow, micronaut-inject-groovy,
github-workflow-java-ci, jrebel, testcontainers, sqlserver,
grails-console, views-markup, asset-pipeline-grails, views-json,
gorm-neo4j, asciidoctor, embedded-mongodb, grails-web-console,
logbackGroovy, mongo-sync, shade, geb, properties
-g, --gorm=GORM Implementation
Which GORM Implementation to configure. Possible values: hibernate,
mongodb, neo4j.
-h, --help Show this help message and exit.
-i, --inplace Create a service using the current directory
--jdk, --java-version=<javaVersion>
The JDK version the project should target
--list-features Output the available features and their descriptions
-s, --servlet=Servlet Implementation
Which Servlet Implementation to configure. Possible values: none, tomcat,
jetty, undertow.
-t, --test=TEST Which test framework to use. Possible values: junit, spock.
-v, --verbose Create verbose output.
-V, --version Print version information and exit.
-x, --stacktrace Show full stack trace when exceptions occur.