HTTPRequest (Function)

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Security error in a secure transaction
Retrieving the result
Accessing a password-protected URL
Using a proxy
Authentication headers

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HTTPRequest (Function)

In french: HTTPRequête

Warning
From version 28, this function is kept for compatibility only (especially for PHP programming). It is recommended to use a variable of type httpRequest with the HTTPSend function.

Starts an HTTP request on a server. The result of the query (buffer) can be:

saved in a backup file with HTTPDestination
retrieved by HTTPGetResult.

Conseil: Use HTTPSend to execute an HTTP request. This function uses an httpRequest variable in order to precisely describe the HTTP request.

Remarks:

Two types of requests are supported: POST and GET. The GET requests are automatic. If the "Message to send" is not specified, it is a GET request (see the syntax). To manage forms, it is recommend to use form-specific functions (HTTPCreateForm, HTTPSendForm, etc.).

Example

See additional examples

// Retrieve the HTML code of "www.windev.com" Web page
ResStart = HTTPRequest("http://www.windev.com")

// Retrieve an HTML page that uses a protected URL
ResStart = HTTPRequest("http://www.windev.com", ...
"", "", "", "", "Julia", "Password")

Syntax

<Result> = HTTPRequest(<URL to contact> [, <User agent> [, <Additional HTTP header> [, <Message to send> [, <Message type> [, <Username> [, <Password>]]]]]])

<Result>: Boolean

True if the request was started,
False if an error occurs. To get more details on the error, use ErrorInfo with the errMessage constant.
The result of the request can be saved in a backup file by HTTPDestination or it can be retrieved by HTTPGetResult.
Errors concerning transaction security are not returned by the ErrorInfo function: the connection is simply refused.

<URL to contact>: Character string

Address of server to contact (URL address). This parameter can contain:
the port number for connecting to the server. The default value is 80 (corresponds to a server of Web pages). To specify a port number, use the format: "<Server URL>:<Port number>". For example: "http://www.pcsoft.fr:80".
additional parameters. These parameters can be used to perform a search or to fill a form. For example, to search for "pcsoft" on "http://www.google.fr", the URL to contact would be: "http://www.google.fr/search?q=pcsoft".
Remarks:
To specify both the port number and additional parameters, use the format: "<Server URL>:<Port Number>/<Additional Parameters>".
To perform a secure transaction, the URL must start with "https://". In this case, the management mode of requests is always performed by Internet Explorer (for more details, see HTTPConfigure).

<User agent>: Optional character string

Identifies the client. The application name is returned by default.
The content of the response may depend on the user agent (for example, a request performed from a mobile device and a request performed from a PC browser require different pages). In this case, for more details, see the documentation of user agent.

<Additional HTTP header>: Optional character string

Additional HTTP header that will be added to the HTTP message,
Empty string ("") if no HTTP header must be added.

<Message to send>: Optional character string

HTTP message that will be sent to the server. This parameter can be specified only for a request for sending messages (POST request). The message to send must comply with the HTTP protocol used. If this parameter is specified and if it is not empty, it is a POST request; otherwise, it is a GET request (everything else is automatic).

<Message type>: Optional character string

Type of the HTTP message content to be sent to the server. This parameter can be specified only for a request for sending messages (POST request). This parameter corresponds to "Content-Type".
The default message type is: "application/x-www-form-urlencoded".
However, it is possible to enter any value, for example: "text/xml", "application/javascript", "application/json", "application/xml", "image/jpeg", ... To send raw data, which will be read at once by the WEBDEV Application Server, use the following types:
"application/octet-stream".
"text/xml".

<Username>: Optional character string

Name used to access a page with a protected URL (empty string by default). This name is used to identify the user.
Note: By entering the parameters <Nom User> and <Mot de passe>, the corresponding "Authorization:Basic" is automatically generated in the request header..

<Password>: Optional character string or secret string

Password associated with the username (empty string by default). Used to access a page with a protected URL. Caution: The password is transmitted unencrypted over the Internet.
Note: By entering the parameters <Nom User> and <Mot de passe>, the corresponding "Authorization:Basic" is automatically generated in the request header..
New in version 2025
Secret strings: If you use the secret string vault, the type of secret string used for this parameter must be "Ansi or Unicode string".
To learn more about secret strings and how to use the vault, see Secret string vault.

Remarks

Security error in a secure transaction

During a secure transaction, the request may fail due to security errors:

invalid certificate or certificate coming from an unknown company.
the site name specified in the certificate does not correspond to a server.
invalid or expired certificate date.
redirection to a non-secure server.
...

These errors are returned by ErrorInfo.

If one of these errors occurs, you can re-run the request while ignoring the errors. To do so, use the HTTP.IgnoreError variable.

The HTTP.IgnoreError variable can also be used to manage special cases during the secure transactions (ignoring the list of revoked certificates for example).

Error returned by ErrorInfo (with the errCode constant)	Value of HTTP.IgnoreError (these values can be combined)	Description

httpErrorInvalidCertificate Invalid certificate or certificate coming from an unknown company	httpIgnoreInvalidCertificate	The certificate is ignored.
httpErrorInvalidCertificateName The site name specified in the certificate does not correspond to a server	httpIgnoreInvalidCertificateName	The site name specified in the certificate is ignored.
httpErrorExpiredCertificate Invalid or expired certificate date	httpIgnoreExpiredCertificate	The certificate date is ignored
httpErrorRedirectToHTTP Redirection to a non-secure server	httpIgnoreRedirectToHTTP	The redirection to a non-secure server is allowed.
httpIgnoreRedirectToHTTPS Redirection to a secure server	httpIgnoreRedirectToHTTPS	The redirection to a secure server is allowed.
	httpIgnoreRedirection	The redirection to a page is ignored.
	httpIgnoreRevocation	The certificate found in the list of revoked certificates is not checked.

For example:

// Start a request on a secure server
ResStart = HTTPRequest("https://www.MyServer.com")
// If an error occurs
IF ResStart = False THEN
// According to the type of error
SWITCH ErrorInfo(errCode)
// Invalid certificate
// or coming from an unknown company
CASE httpErrorInvalidCertificate:
// Ignore the certificate?
IF YesNo("Security alert detected!", ...
"Invalid certificate.", ...
"Ignore this certificate?") = Yes THEN
HTTP.IgnoreError = httpIgnoreInvalidCertificate
// Start the request again
// while ignoring this error
HTTPRequest("https://www.MyServer.com")
END
// Invalid or expired certificate date
CASE httpErrorExpiredCertificate:
// Ignore the certificate date?
IF YesNo("Security alert detected!", ...
"Certificate date invalid or expired.", ...
"Ignore this date?") = Yes THEN
HTTP.IgnoreError = httpIgnoreExpiredCertificate
// Start the request again
// while ignoring this error
HTTPRequest("https://www.MyServer.com")
END
END
END

Remarks:

When the HTTP queries are run in several threads, the HTTP.IgnoreError variable has a specific value for each thread.
Before version 200057, the errors regarding the security of transactions were ignored. The HTTP.IgnoreError variable was not available.
From version 200057the following errors are handled: httpIgnoreCertificateExpired, httpIgnoreCertificatInvalid, httpIgnoreCertificateNameInvalid, httpIgnoreRevocation. The other errors are ignored. For backward compatibility, all the errors are ignored on the existing projects. These errors are supported on the new projects only.

Retrieving the result

HTTPGetResult is used to retrieve the result of the last HTTP request run.

When a destination file is specified by HTTPDestination:

when HTTPGetResult is used with the httpResult constant, it always returns an empty string ("").
HTTPGetResult associated with the httpHeader constant always returns the header of the HTTP response. This header is not saved in the destination file: only the data is saved.

When the request is over, the destination is canceled and HTTPRequest operates as usual.

Accessing a password-protected URL

To access a password-protected URL, you can:

use the <Username> and <Password> parameters found in the syntax of HTTPRequest.
specify the username and password in the <URL to contact> parameter. For example:
<Res> = HTTPRequest("http://<user>:<password>@<URL to contact>")

Using a proxy

To access the URL specified in HTTPRequest via a proxy, use Proxy.

Authentication headers

The authentication headers are automatically generated in the following cases:

If HTTPRequest uses the syntax with username and password.
If the server URL is password protected.
If Proxy is used.

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