Category: Summary Files Folders Storage Http Paths

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Summary

AppServer provides a small set of JavaScript functions that let you access the underlying file-system, store persistant data, and send standard GET and POST requests to other servers. Functions are detailed by category. The categories are listed above. Click on each for more information. To use these commands, you must include a reference to the System.js file in your HTML files as seen below.

The System.js file is stored inside the AppServer itself, so you don't have to worry about keeping track of files. This also insures that the proper file is delivered: you can't accidently "mask" the file by including it in your app folder.

All of the AppServer functions reside in global object "System". Each function has a corresponding asynchronous function that takes an additional callback parameter. Async functions are nested in the System object under "Async" (ie System.Async) See example below.

System.readAllText("/some_folder/file.txt");

System.Async.readAllText("/some_folder/file.txt", callbackFunction);

Here, System.readAllText will return the contents of the file, while System.Async.readAllText will pass the contents of the file to the callback function once AppServer has read the file. For more information on File commands, see the "Files" category. For infomation on Folder commands, see the "Folders" category.

AppServer provides several functions that allow you to get and set text values in the memory space of the AppServer itself. These functions behave like HTML's LocalStorage but are actually stored in the AppServer. There is also a long-term storage option that stores the text in a file within the "storage" folder in the AppServer's root directory. These value are saved until they are deleted. For more information see the "Storage" category.

AppServer provides functions that make it easy to send GET and POST request to other servers. This can be helpful when you want to link your application to a server or web-service. For more information see the "Http" category.

AppServer differentates between full and relative paths. For more information on how AppServer handles Paths, see the "Paths" category.

System.readAllText ( path:string )

This function returns a string representing the contents of the file specified by the path.

System.Async.readAllText ( path:string , callback:function )

System.readAllLines ( path:string )

This function returns an array where each element contains one line of the file specified by the path.

System.Async.readAllLines ( path:string, callback:function )

System.writeAllText ( path:string , contents:string )

This function writes the provided contents to the file specified by the path.

System.Async.writeAllText ( path:string , contents:string, callback:function )

System.writeAllLines ( path:string, lines:array )

This function writes a file specified by the provided path where each element of the array is treated as one line of the file.

System.Async.writeAllLines ( path:string, lines:array, callback:function )

System.copyFile ( srcPath:string , destPath:string )

This function copies the file at the source path location (srcPath) to the destination path (destPath).

System.Async.copyFile ( srcPath:string , destPath:string , callback:function )

System.moveFile ( srcPath:string , destPath:string )

This function moves the file at the source path location (srcPath) to the destination path (destPath).

System.Async.moveFile ( srcPath:string , destPath:string , callback:function )

System.deleteFile ( path:string )

This function deletes the file at the specified path.

System.Async.deleteFile ( path:string , callback:function )

System.fileExists ( path:string )

This function returns true if the file exists and false if the file does not exist or could not be accessed.

System.Async.fileExists ( path:string , callback:function )

System.fileSize ( path:string )

This function returns the size of the file in bytes. This function returns -1 if the file does not exist or could not be accessed.

System.Async.fileSize ( path:string , callback:function )

System.createFolder ( path:string )

This function creates a folder at the specified path.

System.Async.createFolder ( path:string , callback:function )

System.copyFolder ( srcPath:string , destPath:string )

This function copies the folder at the source path location (srcPath) to the destination path (destPath). The folder and it's contents are copied.

System.Async.copyFolder ( srcPath:string , destPath:string , callback:function)

System.moveFolder ( srcPath:string , destPath:string )

This function moves the folder at the source path location (srcPath) to the destination path (destPath). The folder and it's contents are moved.

System.Async.moveFolder ( srcPath:string , destPath:string , callback:function)

System.deleteFolder ( path:string )

This function deletes the folder and its contents at the specified path.

System.Async.deleteFolder ( path:string , callback:function )

System.folderExists ( path:string )

This function returns true if the folder exists and false if the folder does not exist or could not be accessed.

System.Async.folderExists ( path:string , callback:function )

System.folderContents ( path:string )

This function returns an object with two properties: files, and folders. The files property contains an array of full file paths to each file within the folder. The folders property contains an array of full sub-folder paths to each sub-folder within the the folder specified by the path.

NOTE: This function does a "shallow" dredge of the specified folder. So if the specified folder contains subfolders, the contents of those subfolders is NOT contained in the results.

System.Async.folderContents ( path:string , callback:function )

System.setValue ( name:string , value:string )

This function stores a name / value pair that can be accessed by any page running on the App Server. This storage is persistant until the App Server closes. This is NOT the browser's local storage. It is managed by the App Server. Values can also be deleted using the deleteValue command.

System.Async.setValue ( name:string , value:string , callback:function )

System.getValue ( name:string )

This function returns a value stored under the provided name, or returns "undefined" if the value is not present. This storage is persistant until the App Server closes. This is NOT the browser's local storage. It is managed by the App Server. Values can also be deleted using the deleteValue command.

System.Async.getValue ( name:string , callback:function )

System.deleteValue ( name:string )

This function deletes the name / value pair stored under the provided name in the AppServer session. This storage is persistant until the App Server closes or this command deletes the value. This is NOT the browser's local storage. It is managed by the App Server.

System.Async.deleteValue ( name:string , callback:function )

System.setStorage ( name:string , value:string )

This function stores a name / value pair that can be accessed by any page running on the App Server. These values are stored on the file system in the same directory as the AppServer.exe in a folder called "storage". Files within this folder are stored as "[name].store" where [name] is the provided name. This is NOT the browser's local storage. It is managed by the App Server. These values persist on the hard-drive until they are deleted. Storage values can be deleted with the deleteStorage command.

System.Async.setStorage ( name:string , value:string , callback:function )

System.getStorage ( name:string )

This function returns a value stored in the storage directory under the provided name, or returns "undefined" if the storage file is not present. These values are stored on the file system in the same directory as the AppServer.exe in a folder called "storage". Files within this folder are stored as "[name].store" where [name] is the provided name. This is NOT the browser's local storage. It is managed by the App Server. These values persist on the hard-drive until they are deleted. Storage values can be deleted with the deleteStorage command.

System.Async.getStorage ( name:string , callback:function )

System.deleteStorage ( name:string )

This function deletes the name / value pair stored in the storage directory. These values are stored on the file system in the same directory as the AppServer.exe in a folder called "storage". Files within this folder are stored as "[name].store" where [name] is the provided name. This is NOT the browser's local storage. It is managed by the App Server. These values persist on the hard-drive until they are deleted manually, or by using this function.

System.Async.deleteStorage ( name:string , callback:function )

System.httpGet ( url:string )

This function sends a standard HTTP GET request based on the provided url, waits for a response, then returns the responseText. Use the Async version below if you do not want to wait for the server to respond. GET args can be specified after the url. For Example:

var resp = System.httpGet("http://somesite.com/foo.php?a=test&b=something else")

System.Async.httpGet ( url:string, callback:function )

System.httpPost ( url:string, postData:string )

This function sends a standard HTTP POST request based on the provided url and optional postString, waits for a response, then returns the responseText. Use the Async version below if you do not want to wait for the server to respond. GET args can be specified at the end of the url. However, POST args are passed in as a seperate string in the second parameter. AppServer does not handle binary POST data. All POST args must be passed as a string.

System.Async.httpGet ( url:string, postData:string, callback:function )

Paths

The App Server handles both full and relative paths. Any function in System.js that takes a path as input can take a full path, relative path, or network path.

Relative Paths

These are paths that start in the same directory where AppServer.exe resides. So, if the AppServer.exe is sitting in "C:/web_stuff/app/", and you called:

System.readAllText("example.txt");

the path would be translated to "C:/web_stuff/app/example.txt". This makes it easy to drop files into the "C:/web_stuff/app/" folder and reference them in your code using the relative path.

Drive Letter Paths (Full Path)

These are paths that use a drive letter as a reference. For example "C:/web_stuff/app/example.txt" is a "drive-letter" path. If you need to access a file that is NOT in app folder, you can specify the entire path.

Network paths

These are paths that specify a network share using the "\\" prefix. For example, "\\fileserver1\web_stuff\app\". these paths are valid assuming you have connectivity.