How to use the command gow (with examples)

The gow command is a tool for watching Go files and automatically restarting the application when changes are detected. This can be incredibly useful during development, as it eliminates the need to manually restart the application every time a change is made to the code.

Use case 1: Start and watch the current directory

Code:

gow run .

Motivation: This command starts the application and watches all the Go files in the current directory for changes. It is a convenient way to automatically restart the application whenever any modifications are made to the code.

Explanation:

• gow is the command itself.
• run is the subcommand used to start the application.
• . specifies that the current directory should be watched for changes.

Example output:

Server started at http://localhost:8000
Watching...

Use case 2: Start the application with specified arguments

Code:

gow run . argument1 argument2 ...

Motivation: Sometimes, when starting the application, we may need to provide additional arguments or flags. This use case demonstrates how to start the application with specific arguments.

Explanation:

• gow is the command itself.
• run is the subcommand used to start the application.
• . specifies that the current directory should be watched for changes.
• argument1, argument2, … are the additional arguments to be passed to the application.

Example output:

Server started at http://localhost:8000
Listening on port 8000
Using argument1, argument2, ...

Use case 3: Watch subdirectories in verbose mode

Code:

gow -v -w=path/to/directory1,path/to/directory2,... run .

Motivation: In certain cases, we may want to watch specific subdirectories rather than the entire current directory. This example demonstrates how to use the -w flag to specify the directories to be watched and the -v flag for verbose output.

Explanation:

• gow is the command itself.
• -v enables verbose mode, which provides more detailed output.
• -w=path/to/directory1,path/to/directory2,... specifies the directories to be watched. Separate multiple directories using commas.
• run is the subcommand used to start the application.
• . specifies that the current directory should be watched for changes.

Example output:

Watching directory: path/to/directory1
Watching directory: path/to/directory2
Server started at http://localhost:8000

Use case 4: Watch specified file extensions

Code:

gow -e=go,html run .

Motivation: In some cases, we may only want to watch specific file extensions. This example demonstrates how to use the -e flag to specify the file extensions to be watched.

Explanation:

• gow is the command itself.
• -e=go,html specifies the file extensions to be watched. Separate multiple extensions using commas.
• run is the subcommand used to start the application.
• . specifies that the current directory should be watched for changes.

Example output:

Watching file extensions: go, html
Server started at http://localhost:8000

Use case 5: Display help

Code:

gow -h

Motivation: If you ever need a reminder of how to use the gow command and its available options, you can use the -h flag to display the help information.

Explanation:

• gow is the command itself.
• -h displays the help information.

Example output:

Usage: gow COMMAND [ARGS]

Commands:
  run       Start the application and watch for changes
  version   Display version information

Options:
...

Conclusion:

The gow command is a powerful tool for automatically restarting Go applications when changes are detected. By using the provided examples, you can leverage the various options and flags to customize the behavior of gow to suit your specific needs during development. Happy coding!