HTTP Service

HTTP Service receives HTTP requests from clients and responds to them by returning the HTML files that correspond to the requested URL. It is a session service – that is, it is installed on both dispatcher and server nodes to process more client requests. HTTP Service is developed in accordance with HTTP 1.1 specification (RFC 2068).

Visual Administrator

Runtime Control

The system administrator at runtime can set the following properties from the “Runtime” tab of the Visual Administrator tool. This can be done only on server nodes of the cluster:

Host – specifies the name of the host. There is a primary host, named as default. You can also set additional virtual hosts.
Root Directory – the installation program does not create the main directory for the HTTP files automatically. It must be created additionally, or the path must be redirected to an existing directory. The default value is ../../docs .
Start Page – the page displayed when the browser establishes a connection with the host. The server searches for the start page in the root directory, so it is not necessary to specify the path.
Alias – a list of aliases of the HTTP Server that browsers can use if the first name in the path to the document is an alias. No special characters (for example, /) can be used in the aliases. The alias must end with “\“ so the HTTP Server can recognize it. The list of aliases is composed of the pairs Alias and Path, representing the name of the alias and the actual path it stands for respectively.

Visual Administrator toolbar provides the following option for HTTP Service runtime control:

– clears HTTP cache

Properties

	Dispatcher
Property Key	Description	Default Value
General Properties

Port	Specifies the port where the service listens for HTTP requests.	80
Socket queue	Specifies maximum queue length for incoming connection indications.	200
SSL port	Specifies the port for security connections where the service listens for HTTPS requests.	443
Accepting threads count	Specifies the number of threads that wait to be acted on by the socket.	10
ExtraLayers	Specifies the classes that parse the headers of the http requests. Each class must implement one interface. When more than one class is specified, they are separated by a comma. If this property in not specified, the communication protocol is pure HTTP.	com.inqmy.services.httpserver.dispatcher.ICMExtraLayerV1
KeepAliveTimeout	The period (in seconds) from the last server response to the client until the server shuts the client-server connection down. The value of this property is an integer. If set to 0 or less, there is no timeout.	15

	Server
Property Key	Description	Default Value
General Properties

File buffer size	This is the maximum size of the buffer when downloading a file.	4096
KeepAliveEnabled	Specifies whether a connection is “kept alive” or is closed each time.	true
Min File Length For LDT	If the file size is bigger than the specified length, it is transferred by Long Data Transfer.	204800
Log in Common Log Format	The current state of the HTTP Service can be stored in the common log format. Thus, it can be restored in case of a crash.
LogFile (CLF)	Specifies the path to the common log file. Note : It is active only if the “Log in Common Log Format” indicator is set.	./services/http/work/http.log
Use Cache	If this indicator is set, cache is used.
Max File Length	The maximum file size that can be written to the cache.	16348
Cache size	The number of files in cache.	1000
Directory List	If the default file cannot be found in the current directory, the server returns a list of directories.
InferNames	If the server cannot find the start page indicated in the “Start Page” field (it may be left empty), it searches for these listed filenames (in order of appearance). The first one found is returned to the browser.
EnableZipped Response	Determines if the service returns the requested file to the client as ZIP archive.	true
NotZippedFiles	A comma-separated list of file extensions. Files with such extensions are either inappropriate to archive or they already represent different types of archives and do not need additional reduction of their size.
CacheTimeout	The period (value range from 1 to 15 seconds) until the system checks the version of all files in the cache and updates them. If set to 0 or less, this option is switched off.	-1
SapCacheControl	The period (in seconds) for which requests are kept in the ICMan cache. If a second equal request comes up within the specified period, the same response is returned straight from ICMan (without requesting SAP J2EE Engine again).	86400
MIME Types

MIME Types	A list of file extensions and their associated mime types. These types are known to the server. If a type is unknown to the server, it returns “content/unknown.”

Console Administrator

HTTP Service can be administered using the Shell commands from the HTTP command group as well.

Note: For information on HTTP shell commands, refer to the Shell Commands Reference section.

Property Files

../cluster/dispatcher/services/http/properties
HTTP Service properties specified in the Visual Administrator section can be set from this property file as well.

../cluster/server/services/http/properties
HTTP Service properties specified in the Visual Administrator ® Properties section can be set from this property file as well.

../cluster/server/services/http/default.properties
HTTP Service properties specified in the Visual Administrator ® Runtime Control section can be set from this property file as well.

Critical Information and Troubleshooting Tips

For the proper functioning of HTTP Service, it is critical that the port for connections is specified. If the default port is already in use on the same machine, the system administrator must make sure that another value is given to the Port property of HTTP Service. However, if it is running on different machines, you can use the same value for the Port property. The Host property value may be either a hostname or FQDN (Fully Qualified Domain Name), or be specified in dotted quad notation (the IP address). Note that all added virtual hosts must be registered on local or global DNS servers to be located when such a host is requested. Setting the Root Directory is also important for the service. It is recommended that the default values provided (especially Port) be kept.