Advanced Sencha Cmd

Contents

Installation Considerations
Configuration
Command Line Details
Plugins
Use in Ant

This guide covers capabilities of Sencha Cmd available to advanced users. Before using the functionality described in this guide, you should have read Introduction to Sencha Cmd and have a thorough understanding of Sencha Cmd basics.

Installation Considerations

Location

The Installer lets you select a destination path, but changing this can have side effects (see the section "Multiple Installed Versions"). Ideally, all versions of Sencha Cmd are installed in a single base folder with sub-folders named by the version number. On Windows, the default install folder for a single-user installation looks like this:

C:\Users\myself\bin\Sencha\Cmd.0.0.181\

It is highly recommended that if you change this path, you preserve the last piece (that is, the version number) as well as install any other versions of Sencha Cmd in that same parent folder.

Multiple Installed Versions

At the command prompt, all calls to sencha land in the most recently installed version of Sencha Cmd. Sometimes this version may not be compatible with the current application.

To support such scenarios, Sencha Cmd looks at the required version as specified by the framework used by the application. It then delegates the command to the the proper version of Sencha Cmd.

Important. For this to work properly, both versions must be installed in a folder named by their version number and located in a common parent folder.

Alternatively, each installed version also provides a version-specific name for Sencha Cmd. This can be run as follows:

sencha-3.0.0 ....

Finally, the installer also sets an environment variable of the form SENCHA_CMD_3_0_0, which can be used to adjust the PATH of the current console/shell, as follows.

On Windows, this looks like this:

set PATH=%SENCHA_CMD_3_0_0%;%PATH%
sencha ....

On OSX/Linux, this looks like this:

set PATH=$SENCHA_CMD_3_0_0:$PATH
sencha ....

Configuration

Any parameter that can be passed to Sencha Cmd on the command line can be set as a configuration option in one of the configuration files discussed below. If you know the command line option, it is a simple matter to add that option to a configuration file.

For example, to specify the name parameter for sencha generate app in the configuration, add this line:

sencha.generate.app#name=MyApp

This particular property is not meaningful to specify in a configuration file, but it serves to illustrate the syntax. The parts of the command that goes before the # are the Sencha Cmd commands separated by dots. Following the # is the option name.

To set global options (like debug logging), do this:

sencha#debug=true

Configuration becomes more important over time as Sencha Cmd (especially the compiler) evolves.

Configuration Files

Configuration is applied in a simple cascade starting with the configuration file found in the Sencha Cmd folder called "sencha.cfg". This contains the default configuration for Sencha Cmd. All properties in that file are loaded as Sencha Cmd launches.

Following that base file, the framework, workspace and finally application configurations are loaded, overriding any commonly named properties. This is the order of configuration file loading:

${cmd.dir}/sencha.cfg
${framework.dir}/sencha.cfg
${workspace.dir}/.sencha/workspace/sencha.cfg
${app.dir}/.sencha/app/sencha.cfg

Command Line Details

Here are some helpful tricks if you make frequent use of Sencha Cmd.

Shortest Unique Prefix

All commands, categories and options in Sencha Cmd can be specified by their full name or by the shortest prefix that is unique.

To illustrate, since generate is the only top-level category in Sencha Cmd that currently starts with the letter "g", and likewise, app is the only command in that category that starts with an "a", the following commands are equivalent:

sencha generate app MyApp ../MyApp
sencha g a MyApp ../MyApp

Important. While this can be convenient at the console or terminal, it is not a good practice to use extremely short/terse prefixes in scripts. The use of such terse commands in scripts will needlessly confuse anyone trying to understand or maintain the script in the future and can break if the addition of new commands makes the short form ambiguous.

Command Chaining

The Sencha Cmd command-line processor executes all commands given to it until they have all been dispatched. This means you can avoid the cost of relaunching the whole Sencha Cmd process to execute multiple commands. To take advantage of this, insert and or then between commands.

The and and then commands are based on the execution model of Sencha Cmd and its hierarchical structure of commands and categories. The and command is used to execute another command in the same category as the previous command. This is the most common use case.

For example, to generate a controller and two models, use this:

cd /path/to/MyApp
sencha generate controller Central and model User id:int and model Ticket id,name,email

In the above, the two uses of and caused two generate model commands to be executed. The then command is similar to and, except that the next command will be part of the root category (that is, the sencha command).

For example, the following generates a new model, then builds the application:

cd /path/to/MyApp
sencha generate model User id:int,name then app build

Response Files

When command chaining starts to make command lines too long to be readable, perhaps in a complex build script, you can put command line arguments in a file and tell Sencha Cmd to read arguments from that file.

For example:

cd /path/to/MyApp
sencha @file.sencha

In the above, the "file.sencha" file is read and each line is taken to be a command line argument, unless that line begins with "#", in which case it is skipped. All lines from the specified file are inserted into the command line arguments as if they had been typed there instead of "@file.sencha". This means that "file.sencha" can contain response file insertions as well (for example, "@file2.sencha").

Category State

For performance reasons, some categories maintain state across multiply executed commands. The best example of this is the new compile category of commands. Instead of reading all the sources for each command, the compile category maintains a cache of all the files in the class path. This context is then available to all of the commands in the category.

The following command rebuilds the ext-all-dev.js and ext-all.js files while reading the framework sources only once:

cd /path/to/MyApp
sencha compile -c sdk/src --debug=true concat -o sdk/ext-all-dev.js \
    and --debug=false concat -c -o sdk/ext-all.js

If you don't want to use this caching, perhaps because the set of files is not the same for the next set of outputs, use the then command, like this:

cd /path/to/MyApp
sencha compile -c sdk/src --debug=true concat -o sdk/ext-all-dev.js \
     then compile -c app/foo --debug=true concat -o app/foo/foo-all.js

At present, only the compile category maintains state across commands.

Plugins

While the same Sencha Cmd install is used by both Ext JS and Sencha Touch, there are many times when commands perform slightly different operations depending on the framework. Further, some commands may only be available for one framework.

To accommodate this, the functionality of Sencha Cmd is partitioned across two layers: the command line (properly called "Sencha Cmd") and the lower-level interface for use in Ant. Commands that have these special concerns are routed from the command line into a plugin.

A Sencha Cmd plugin is just an Ant script contained in a file called "plugin.xml" though for any given command, executed in an application or workspace, there are potentially several active plugins.

The process begins by looking for the most specific plugin available. The search goes like this:

${app.dir}/.sencha/app/plugin.xml
${workspace.dir}/.sencha/workspace/plugin.xml
${cmd.dir}/plugins/${framework.name}/${framework.plugin.version}/plugin.xml
${cmd.dir}/plugin.xml (also known as the "default plugin")

The first of these to be found will be based on the current directory. Sencha Cmd will then load only that plugin and invoke specific targets based on the command it was given. These plugins, however, contain the Ant invocation required to load the plugin at the next level up. For example, if the application plugin is found, it contains an import of the workspace plugin. That plugin contains an import of the framework plugin and, lastly, that contains an import of the default plugin.

Extension Points

Technically, the lowest two levels (the framework and default plugins) are the only plugins that contain actual code. The application and workspace plugins are empty by default but are present to allow for user extension of these built-in commands. The purpose for this is to allow you to add logic to enforce project or application standards for code generation requests made to Sencha Cmd.

If you want to check to see if new model definitions follow project guidelines, say that the first field is always id:string, you could add something this to the application or workspace "plugins.xml":

<target name="-before-generate-model">
    <if>
        <not><matches string="${args.fields}" pattern="^id\:string,.*"/></not>
        <then>
            <fail>Models must have "id:string" as first field.</fail>
        </then>
    </if>
</target>

Similarly you could also provide a hook to update other systems when a new model has been added.

<target name="-after-generate-model">
    ... post new/updated Model ${args.name} and ${args.fields} ...
</target>

The actual target names will be slightly different based on which plugin you extend. For specifics, consult the comments in the respective "plugin.xml" file.

Note. The default "plugin.xml" file imports Ant Contrib which provides many useful tasks.

Use in Ant

While the primary use of Sencha Cmd is at the command line (hence its name), Sencha Cmd is also usable directly from Ant. For details about the many commands provided at this level, see the Ant Integration guide.