IncomingMessage
The 4D.IncomingMessage
class allows you to handle the object received by a custom HTTP request handler. HTTP requests and their properties are automatically received as an instance of the 4D.IncomingMessage
class. Parameters given directly in the request with GET verb are handled by the .urlQuery
property, while parameters passed in the body of the request are available through functions such as .getBlob()
or getText()
.
The HTTP request handler can return any value (or nothing). It usually returns an instance of the 4D.OutgoingMessage
class.
All properties of this class are read-only. They are automatically filled by the request handler.
História
Release | Mudanças |
---|---|
20 R8 | Classe adicionada |
Exemplo
The following HTTPHandlers.json file has been defined:
[
{
"class": "GeneralHandling",
"method": "gettingStarted",
"pattern": "start",
"verbs": "get, post"
}
]
The http://127.0.0.1/start/example?param=demo&name=4D
request is run with a GET
verb in a browser. It is handled by the gettingStarted function of the following GeneralHandling singleton class:
shared singleton Class constructor()
Function gettingStarted($request : 4D.IncomingMessage) : 4D.OutgoingMessage
var $result:=4D.OutgoingMessage.new()
var $body : Text
$body:="Called URL: "+$request.url+"\n"
$body+="The parameters are received as an object: \n"+JSON Stringify($request.urlQuery; *)+"\n"
$body+="The verb is: "+$request.verb+"\n"
$body+="There are "+String($request.urlPath.length)+" url parts - Url parts are: "\
+$request.urlPath.join(" - ")+"\n\n"
$result.setBody($body)
$result.setHeader("Content-Type"; "text/plain")
return $result
The request is received on the server as $request, an object instance of the 4D.IncomingMessage class.
Here is the response:
Called URL: /start/example? param=demo&name=4D
The parameters are received as an object:
{
"param": "demo",
"name": "4D"
}
The verb is: GET
There are 2 url parts - Url parts are: start - example
IncomingMessage Object
4D.IncomingMessage objects provide the following properties and functions:
.getBlob() : Blob returns the body of the request as a Blob |
.getHeader( key : Text ) : Text returns the value of the key header |
.getJSON() : Variant returns the body of the request as a JSON resolution |
.getPicture() : Picture returns the body of the request as a picture (in case of a body sent as a picture) |
.getText() : Text returns the body of the request as a text value |
headers : Object the current headers of the incoming message as key/value pairs (strings) |
url : Text the URL of the request without the IP:port part and as a string |
urlPath : Collection the URL of the request without the IP:port part and as a collection of strings |
urlQuery : Object the parameters of the request when they have been given in the URL as key/value pairs |
verb : Text the verb used by the request |
Um objeto 4D.IncomingMessage é um objeto não compartilhável.
.getBlob()
.getBlob() : Blob
Parâmetro | Tipo | Descrição | |
---|---|---|---|
Resultados | Blob | <- | Body of the request as a Blob |
Descrição
The .getBlob()
function returns the body of the request as a Blob.
If the body has not been given as a binary content, the function tries to convert the value but it can give unexpected results.
.getHeader()
.getHeader( key : Text ) : Text
Parâmetro | Tipo | Descrição | |
---|---|---|---|
| | Text | -> | Header property to get |
Resultados | Text | <- | Value of the header property |
Descrição
The .getHeader()
function returns the value of the key header.
The key parameter is not case sensitive.
Exemplo
var $value : Text
var $request : 4D.IncomingMessage
$value := $request.getHeader("content-type")
.getJSON()
.getJSON() : Variant
Parâmetro | Tipo | Descrição | |
---|---|---|---|
Resultados | Diferente de | <- | JSON resolution of the body of the request |
Descrição
The .getJSON()
function returns the body of the request as a JSON resolution.
If the body has not been given as JSON valid content, an error is raised.
.getPicture()
.getPicture() : Picture
Parâmetro | Tipo | Descrição | |
---|---|---|---|
Resultados | Imagem | <- | Body of the request as picture |
Descrição
The .getPicture()
function returns the body of the request as a picture (in case of a body sent as a picture).
The content-type must be given in the headers to indicate that the body is a picture.
If the request is built using the HTTPRequest
class, the picture must be sent in the body as a Blob with the appropriate content-type.
If the body is not received as a valid picture, the function returns null.
.getText()
.getText() : Text
Parâmetro | Tipo | Descrição | |
---|---|---|---|
Resultados | Text | <- | Body of the request as text |
Descrição
The .getText()
function returns the body of the request as a text value.
If the body has not been given as a string value, the function tries to convert the value but it can give unexpected results.
.headers
headers : Object
Descrição
The .headers
property contains the current headers of the incoming message as key/value pairs (strings).
The .headers
property is read-only.
Header names (keys) are lowercased. Note header names are case sensitive.
.url
url : Text
Descrição
The .url
property contains the URL of the request without the IP:port part and as a string.
For example, if the request is addressed to: "http://127.0.0.1:80/docs/invoices/today", the .url
property is "/docs/invoices/today".
The .url
property is read-only.
The "host" part of the request (IP:port) is provided by the host
header.
.urlPath
urlPath : Collection
Descrição
The .urlPath
property contains the URL of the request without the IP:port part and as a collection of strings.
For example, if the request is addressed to: "http://127.0.0.1:80/docs/invoices/today", the .urlPath
property is ["docs", "invoices" ,"today"].
The .urlPath
property is read-only.
.urlQuery
urlQuery : Object
Descrição
The .urlQuery
property contains the parameters of the request when they have been given in the URL as key/value pairs.
The .urlQuery
property is read-only.
Parameters can be passed in the URL of requests directly or as JSON contents.
Direct parameters
Example: http://127.0.0.1:8044/myCall?firstname=Marie&id=2&isWoman=true
In this case, parameters are received as stringified values in the urlQuery
property: urlQuery = {"firstname":"Marie" ,"id":"2" ,"isWoman":"true"}
JSON contents parameters
Example: http://127.0.0.1:8044/myCall/?myparams='[{"firstname": "Marie","isWoman": true,"id": 3}]'
.
Parameters are passed in JSON format and enclosed within a collection.
In this case, parameters are received as JSON text in the urlQuery
property and can be parsed using JSON Parse
.
//urlQuery.myparams: "[{"firstname": "Marie","isWoman": true,"id": 3}]"
$test:=Value type(JSON Parse($r.urlQuery.myparams))=Is collection) //true
Special characters such as simple quotes or carriage returns must be escaped.
Example: http://127.0.0.1:8044/syntax/?mdcode=%60%60%604d
//urlQuery.mdcode = ```4d
$test:=Length($r.urlQuery.mdcode) //5
Parameters given in the body of the request using POST or PUT verbs are handled through dedicated functions: getText()
, getPicture()
, getBlob()
, getJSON()
.
.verb
verb : Text
Descrição
The .verb
property contains the verb used by the request.
HTTP and HTTPS request verbs include for example "get", "post", "put", etc.
The .verb
property is read-only.