FetchRemote: Difference between revisions
m ("error" is a reserved keyword.) |
(Warning for using toJSON in requests.) |
||
Line 5: | Line 5: | ||
In the case when the call fails, a string containing "ERROR" followed by an integer containing the error reason will be passed to the callback function. The reason for failure will be similar to errors found with websites - file not found, server not found and timeouts. | In the case when the call fails, a string containing "ERROR" followed by an integer containing the error reason will be passed to the callback function. The reason for failure will be similar to errors found with websites - file not found, server not found and timeouts. | ||
If you are using fetchRemote to connect to a PHP script, you can use ''file_get_contents( | If you are using fetchRemote to connect to a PHP script, you can use '''file_get_contents('php://input')''' to read the '''postData''' sent from this function. | ||
{{Note|Client side function only works with the server the player is connected to unless the domain has been accepted with [[requestBrowserDomains]]}} | {{Note|Client side function only works with the server the player is connected to unless the domain has been accepted with [[requestBrowserDomains]]}} | ||
{{ Warning| function won't trigger inside another fetchRemote function }} | {{ Warning| function won't trigger inside another fetchRemote function }} | ||
{{ Warning| When using [[toJSON]] for submitting data, make sure to use string.sub(data, 2, -2) to remove the brackets as many APIs will not understand the request }} | |||
==Syntax== | ==Syntax== | ||
<syntaxhighlight lang="lua"> | <syntaxhighlight lang="lua"> |
Revision as of 09:28, 12 July 2024
This function allows you to post and receive data from HTTP servers. The calls are asynchronous so you do not get an immediate result from the call, instead a callback function you specify is called when the download completes.
In the case when the call fails, a string containing "ERROR" followed by an integer containing the error reason will be passed to the callback function. The reason for failure will be similar to errors found with websites - file not found, server not found and timeouts.
If you are using fetchRemote to connect to a PHP script, you can use file_get_contents('php://input') to read the postData sent from this function.
Syntax
bool fetchRemote ( string URL, [ string queueName = "default" ], [ int connectionAttempts = 10, int connectTimeout = 10000 ], function callbackFunction, [ string postData = "", bool postIsBinary = false ], [ arguments... ] )
Required Arguments
- URL: A full URL in the format http://hostname/path/file.ext. A port can be specified with a colon followed by a port number appended to the hostname.
- callbackFunction: This is the function that should receive the data returned from the remote server. The callback argument list should be:
- responseData - A string containing the remote response or "ERROR" if there was a problem
- error - A number containing the error number or zero if there was no error. A list of possible error values are:
- 1-89: See cURL website or its mirror at cURL errors
- 400-599: See HTTP status codes
- 1002: Download aborted
- 1003: Failed to initialize
- 1004: Unable to parse url
- 1005: Unable to resolve host name
- 1006: Destination IP not allowed
- 1007: File error
- arguments... - The arguments that were passed into fetchRemote
Optional Arguments
- connectionAttempts: Number of times to retry if the remote host does not respond. In the case of a non-responding remote server, each connection attempt will timeout after 10 seconds. Therefore, the default setting of 10 connection attempts means it will be 100 seconds before your script gets a callback about the error. Reducing this value to 2 for example, will decrease that period to 20 seconds
- connectTimeout: Number of milliseconds each connection attempt will take before timing out
- postData: A string specifying any data you want to send to the remote HTTP server.
- postIsBinary : A boolean specifying if the data is text, or binary.
- arguments: Any arguments you may want to pass to the callback.
Returns
Example
This example shows you how you can fetch an image from a web page, and transfer it to a particular client:
function startImageDownload( playerToReceive ) fetchRemote ( "http://www.example.com/image.jpg", myCallback, "", false, playerToReceive ) end function myCallback( responseData, errorCode, playerToReceive ) if errorCode == 0 then triggerClientEvent( playerToReceive, "onClientGotImage", resourceRoot, responseData ) end end
addEvent( "onClientGotImage", true ) addEventHandler( "onClientGotImage", resourceRoot, function( pixels ) if myTexture then destroyElement( myTexture ) end myTexture = dxCreateTexture( pixels ) end ) addEventHandler("onClientRender", root, function() if myTexture then local w,h = dxGetMaterialSize( myTexture ) dxDrawImage( 200, 100, w, h, myTexture ) end end )
Requirements
This template will be deleted.
Changelog
Version | Description |
---|
1.3.1-9.04605 | Added connectionAttempts argument |
1.3.2 | Added client side |
1.5.3-9.11270 | Added queueName argument |
1.5.4-9.11342 | Added alternative syntax |
1.5.4-9.11413 | Added formFields |
See Also
- abortRemoteRequest
- call
- fetchRemote
- getResourceConfig
- getResourceDynamicElementRoot
- getResourceExportedFunctions
- getResourceFromName
- getResourceName
- getResourceRootElement
- getResourceState
- getThisResource
- getRemoteRequests
- getRemoteRequestInfo