MacHTTP Read MeMacHTTP Read MeThe server places a very small load on your Mac, both in memory and CPU requirements. It should run fine in the background on any Mac with MacTCP installed and System 7.
MacHTTP is being written by Chuck Shotton, from the University of Texas Houston Health Science Center's Office of Academic Computing. Questions can be addressed to cshotton@oac.hsc.uth.tmc.edu. The latest version of MacHTTP can FTPed from oac.hsc.uth.tmc.edu in the public/mac/MacHTTP directory.
Current information about MacHTTP can be found on the MacHTTP home page at http://www.uth.tmc.edu/mac_info/machttp_info.html.
The bug that caused MacHTTP to enter an infinite loop when a script returned HTML text containing a carraige return has been fixed. It should now be possible to do all sorts of nifty stuff like URL redirection and HTTP/1.0 headers from scripts. See the script examples for details.
Also, the timeout value used to tell MacTCP how long to wait for network communications to time out (different than the TIMEOUT command in the config file) has been increased to allow clients accessing MacHTTP via SLIP more time to complete their read or write operations.
MacHTTP is now HTTP/1.0 compatible. Rudimentary support is now included for MIME type mapping. See the comments in the MacHTTP.config file for more details. You must use the upgraded config file format for suffix mappings with this version.
The next major release of MacHTTP (probably 2.0) should be out soon and will have all of the new HTTP/1.0 features documented much more thoroughly.
MacHTTP has been tested on Mac II and Quadra family CPUs and works fine. Unfortunately, MacHTTP doesn't work and play well with 68000-based Macs like SEs and PowerBook 100s. Anyone who figures out why will be rewarded with an immediate upgrade!
Installing MacHTTP is extremely easy. Simply unarchive MacHTTP using a relatively recent version of something like Stuffit Expander or UnStuffit. The resulting folder already has everything installed in the proper places. You may place this folder on any disk, in any location.
Once you have MacHTTP unstuffed, simply double-click the application to activate the server. Use a WWW client like Mac Mosaic to connect to the following URL, substituting your Mac's host name or IP address in place of "your.host.name":
http://your.host.name/
"MacHTTP.config" file
found inside the MacHTTP folder. This file consists of a series keywords and arguments
that adjust various parameters affecting how MacHTTP runs. MacHTTP.config
is a plain text file that can be modified using any text editor, including TeachText.
Each command in the config file must start on a line by itself and each line should start with a keyword. Lines that don't start with a recognized keyword are considered as comments. Arguments specified inside angle brackets ("<", ">") should be replaced with the appropriate value for your server in the config file, omitting the angle brackets.
INDEX <file name>: specifies the Home Page or Index for the server. This is the default document returned if a WWW client accesses your server and specifies the document "/" or no document at all.
If omitted, the default file name is ":Default.html" (no quotes).
ERROR <file name>: specifies the file returned by the server if an error occurs. This is usually an information message informing the user that a requested file cannot be found.
If omitted, the default file name is ":Error.html" (no quotes).
LOG <file name>: specifies the log file for the server. A log of all client accesses is maintained in this file. See the <Log File section below for more details.
If omitted, logging is disabled and no log file will be created.
NOACCESS <file name>: specifies the file to be returned by the server if a client that is not authorized to access the server attempts to request a file. See the Security section below for more details.
If omitted, the default file name is ":NoAccess.html" (no quotes).
Examples:
ERROR :Error.html INDEX :Default.html LOG :MacHTTP.log NOACCESS :NoAccess.html
Note that the file names begin with a ":". This tells MacHTTP to look within the same folder as the application for the files. While not required, it's a good idea to make sure the ":" is included for security reasons.
Also, some files like QuickTime movies and GIF images need to be transmitted to the client as byte for byte copies of the original file, using a "binary" transfer mode. In order to help MacHTTP distinguish which transfer method to use, you may specify up to 10 "suffix mappings" in the config file. These mappings tell MacHTTP whether to use a text or binary file transfer when sending a file, based on the suffix of the file's name.
Last of all, MacHTTP can execute AppleScripts and return the results of the script execution back to WWW clients. MacHTTP needs to be able to differentiate between files that are simply sent directly to the client (i.e., binary and text) and files that must be executed first (i.e., AppleScript).
There can be a maximum of 20 suffix mappings defined in the config file. If fewer than 20 mappings are provided, MacHTTP uses internal defaults to supply the missing mappings. When MacHTTP starts up, the status window displays the 20 suffix mappings plus the default file type for file names that don't match one of the 20 mappings.
TEXT <suffix>: Files ending with the specified suffix will have carraige returns translated to carraige return/line feed before transmission to the client.
BINARY <suffix>: Files ending with the specified suffix will be sent to the client without modification. Only the data fork of the file is transmitted.
SCRIPT <suffix>: Files ending with the specified suffix will be loaded and executed as an AppleScript source file. The script is expected to generate HTML text and return it to MacHTTP as the result of script execution. This result will then be transmitted to the client as TEXT files above.
APPL <suffix>: Files ending with the specified suffix will be treated as an application and launched by MacHTTP. MacHTTP will then pass any arguments to the application using custom AppleEvents. The application is expected to generate HTML text and return it to MacHTTP as the result of processing the AppleEvent. This result will then be transmitted to the client as TEXT files above. See the AppleEvents section below for more details.
DEFAULT <type>: "type" can be one of TEXT, BINARY, or SCRIPT. The DEFAULT command specifies the default file type to be used if a file's suffix doesn't match one of the 20 defined suffix mappings.
Examples:
TEXT .HTML BINARY .GIF SCRIPT .SCRIPT APPL .EXE DEFAULT TEXT
ALLOW <IP address>: Specifies the partial or complete IP address of a host (or hosts) that is allowed to access the server.
DENY <IP address>: Specifies the partial or complete IP address of a host (or hosts) that is denied access to the server.
An unlimited number of security directives may appear in the config file. If none are present, then any client may access the server. If one or more directives is present in the config file, the directives are evaluated in the order they appear in the config file to determine whether a client is allowed to access the server.
If security directives are present in the config file, there is an implicit "DENY *" that is evaluated before any directives in the file. This means that all clients are denied and you must explicitly allow clients by using the ALLOW command to specify complete or partial addresses of clients which can access the server.
Examples:
ALLOW 129.106. DENY 129.106.3 ALLOW 129.106.30.1.
These example statements are evaluated as follows. First, the implicit "DENY *" is evaluated, implying that no hosts may access the server. The first ALLOW statement specifies that all clients with addresses that begin with "129.106." will be allowed to connect to the server.
The DENY statement removes all clients with IP addresses that begin with "129.106.3" from the list of hosts that may access the server. Important note: The DENY statement not only matches all hosts in the "129.106.3" subnet, but also all hosts in "129.106.30", "129.106.31", etc. If you wanted to only restrict hosts in the "129.106.3" subnet, you should add a trailing "." to the IP address (i.e., "129.106.3.").
The final ALLOW statement explicitly enables the host "129.106.30.1". This statement matches only this specific host. MacHTTP always appends a trailing "." when comparing a client's IP address to the security entries. This means to match exactly one host with an ALLOW or DENY statement, the IP address argument must end with a "."
PORT <number>: Specifies the port number that MacHTTP will listen to for all incoming connections. The default is port 80 if this line is omitted from the config file
The minimum number of simultaneous users is 3. Because of the way MacHTTP handles incoming requests and terminates connections, it is possible for a single, fast client to create a new connection before the previous one is dropped by MacHTTP. This, coupled with the fact that MacHTTP always reserves one connection for listening for incoming client requests means that at least 3 connections should be provided for at a minimum.
The maximum number of users is arbitrarily limited to 1000. Since MacHTTP can only transmit the data for one request to a client at a time, all other clients' requests are queued and executed in turn. Setting the maximum number too high will result in intolerable delays for clients. These delays could exceed MacHTTP's timeout value for inactive connections, so it's probably a good idea to leave the maximum users setting somewhere between 8 and 20.
Incoming clients that exceed the maximum number of users will be informed that the server is too busy to handle their request.
MAXUSERS <number>: Specify the maximum number of simultaneous users allowed to connect to MacHTTP. Values between 3 and 1000 are allowed. The default is 8 if this statement is omitted from the config file.
MAXLISTENS <number>: Defines the number of simultaneous listens for incoming client connections. Values between 3 and 50 are allowed. The default is 5.
TIMEOUT <seconds>: Specifies the maximum amount of idle time in seconds before MacHTTP disconnects a client's inactive connection. The minimum value is 15 seconds. The maximum value is 600 seconds and the default is 90 seconds if this statement is omitted from the config file.
HIDEWINDOW: If this command is present in the config file, MacHTTP's status window will be hidden when the application is running in the background.
All MacHTTP menu functions can be invoked via AppleEvents. So if MacHTTP is running on a "headless" Mac or you want to use AppleScript to control its behavior, you may execute any of the menu commands from another application. See the "Scripting and MacHTTP" section below or examine MacHTTP's AppleEvent dictionary (aete reource) for more details.
Verbose Messages: Causes MacHTTP to produce much more status information about client requests and what the program is doing internally. You should enable this option if you are having trouble with MacHTTP and aren't sure what's going on. The cryptic nature of these messages is sure to help add to the confusion, since most pertain to internal MacTCP state information. However, some of the messages are useful for watching details of client requests, etc.
Suspend Logging: Temporarily closes MacHTTP's log file (if a log file is specified in the config file), allowing you to open and examine the log file with a text editor. All incoming connection information will not be logged to the file while this option is enabled.
Hide Window in Background: Works the same as the HIDEWINDOW command in the config file, described above.
Refuse New Connections: This option allows busy servers to remain running, but not allow any new clients to connect. All currently queued clients will be served, but no new connections will be accepted. Clients will be notified that connections are being refused. This option is useful for gracefully shutting down a server, or allowing you to change HTML documents while the server is running.
It is important to note that MacHTTP can interpret both Unix and Mac file specifications. Typically, HTML documents are written using Unix path names, etc. while file names specified within MacHTTP's config file use Mac file naming conventions.
MacHTTP also understands Macintosh aliases. If you create an alias to a document for MacHTTP to serve, MacHTTP will use the name of the alias for suffix mapping, then translate the alias to find the original file's contents.
This means that the "root" of MacHTTP's file system starts with the folder it resides in. Clients requesting documents from MacHTTP specify URLs as if MacHTTP was at the root of the file system.
NOTE: While you can use aliases to original files that aren't contained within the MacHTTP directory tree, any URLs contained in these files must still provide paths that are relative to where MacHTTP resides. This is done for security purposes and isn't subject to change.
To access your default home page, you'd specify the following URL:
To access "sample.html" :
To access "another.html" :
Note that all URLs are relative to the folder containing MacHTTP. No parent directories or disks are specified. MacHTTP handles spaces and special characters in folder and file names, but it's a good idea to avoid spaces and special characters in any file or folder names that MacHTTP will be serving when possible.
MacHTTP tries to deal intelligently with HTTP 1.0 clients (by discarding everything after the path.) It supports query URLs and special character translation in URLs, but not returning data over alternate ports. It also supports returning binary data, so it can be used with clients that support graphics (like Mosaic).
More information on URLs can be obtained from
http://www.ncsa.uiuc.edu/demoweb/url-primer.html.
Information on writing HTML documents for WWW can be obtained from
http://www.ncsa.uiuc.edu/demoweb/html-primer.html.
Here's an example. Suppose you have an Excel spreadsheet file called "BigBucks.xcl". You must make sure that there is an entry in the MacHTTP.config file that looks like:
BINARY .xcl
This tells MacHTTP to transfer files with names ending in ".xcl" to the WWW client without any modifications.
Configuring your WWW client is the next step. If you are using Mac Mosaic, you need to define a file
name extension mapping that maps the ".xcl" suffix into a specific MIME type and
"Helper Application." Once you've done this, selecting a URL like
http://your.machttp.host/BigBucks.xcl
Any WWW client accessing a SCRIPT document will cause MacHTTP to load the source for the script from the file specified in the URL. Two predefined AppleScript variables are created and prepended to the AppleScript source. MacHTTP will then pass the source code to AppleScript for compilation and execution. The result returned from AppleScript is then passed back to the client by MacHTTP.
http_request contains the complete HTTP request received from the WWW client.
http_search_args contains any search arguments passed by the WWW client to
MacHTTP as part of the request. This variable is useful for implementing clickable maps
and searchable documents. See the example script files in the MacHTTP distribution for
more details on how these variables are used.
http_search_args is a variable that is predefined by MacHTTP, prior
to script execution, that contains the search arguments passed by the WWW client.
< ISINDEX> is a HTML tag that indicates the following document is
searchable. Be careful not to confuse "ISINDEX" with the INDEX file specification
described above.
2. MacHTTP prefixes every source file with global variable definitions prior to passing it to AppleScript. A variable called "http_request" contains a string that is the actual argument passed to MacHTTP by the WWW client. This may be useful if you have a client that sends HTML1 requests and you want to do something with the extra arguments in AppleScript.
Another variable, "http_search_args", contains the search arguments, if any, that were passed as part of the client's request. This info is also contained in the http_request variable, but is extracted and provided for easier access here.
See the sample.script and search.script files for examples.
3. You must perform all HTML formatting inside the AppleScript file. MacHTTP only strips off the spurious quotes and converts special characters prior to sending script execution results to the client. Again, see the sample.script file for examples.
4. If MacHTTP is low on memory, scripts that use scripting extensions (OSAX's) will cause the program to hang. Make sure MacHTTP has enough memory (512K for script execution, 384K otherwise).
5. You may place alias files in your MacHTTP directory tree that point to script files. If the alias name ends with a suffix that is defined to be of type "SCRIPT", then the alias will be resolved and the file will be executed.
AppleEvents Received by MacHTTP
Currently, there is only one custom AppleEvent supported by MacHTTP. This event, DoMenu,is used to make MacHTTP execute one of its menu choices. The syntax from AppleScript is:
DoMenu "<menu ID>, < menu item>"
"Menu ID" is the number of the MacHTTP menu, starting with 1 for the Apple menu and ending with 4 for the Options menu. "Menu Item" is the selection within a particular menu. For example:
DoMenu "4,1"
would turn on Verbose Messages (menu 4, Options, item 1, Verbose Messages).
The event suite for the DoMenu event is the same as the 4 character creator code for MacHTTP. This is three upper case "W"s, followed by the omega character (generated by typing option-Z). The event code for DoMenu is the 4 character code, "menu". See the MacHTTP aete resource for more details (MacHTTP's "dictionary" for AppleScript users).
If MacHTTP receives a query (GET) from a WWW client requesting a file whose suffix mapping is APPL (an executable application), MacHTTP will attempt to execute this application and communicate with it via custom AppleEvents. Currently, MacHTTP supports one AppleEvent for communication with traditional Mac applications or AppleScript applications.
Search: The "search" AppleEvent that is part of the MacHTTP suite is sent to applications when they are specified in a URL being requested by a WWW client. MacHTTP will launch the application, and then send this event. Here are the specifics on the search event:
on <<event WWW*srch>> search_args --remember, "*" is the omega char!
will be launched automatically, and the handler will be invoked with search_args appropriately defined. Note that "<<" and ">>" are the single characters obtained by typing option-\ and option-|, respectively.
If you don't want to allow script execution (or don't have AppleScript installed) you can make sure script execution is disabled by modifying the MacHTTP.config file so none of the 10 entries defines a SCRIPT type.
As configured "out of the box", MacHTTP provides no restrictions on which hosts may access your server. Please review the section above that describes the ALLOW and DENY commands in the configuration file, which are used to restrict network access to MacHTTP.
Entries in the log file are separated by tabs, and individual entries are terminated with a carraige return. This format is the standard text-only import format used by most spreadsheet applications (e.g. Excel) and Mac data base applications like FileMaker.
To disable logging, simply delete the log file specification command from the config file (LOG :MacHTTP.log).
Connections:
Memory:
1) MacHTTP is available for use under the following restrictions. Unrestricted use of MacHTTP for the purposes of publishing information on the Internet via WWW is granted to individuals associated with educational and government institutions. These institutions may use MacHTTP at no cost for the purposes listed. MacHTTP may not be used for profit unless permission is obtained from the author and the University of Texas-Houston.
2) MacHTTP is available for use by commercial organizations and those not covered by item 1 above under the terms of a separate license. Please contact the author for commercial licensing information. Under no circumstances may MacHTTP be sold for profit, or included in software anthologies or archives that are distributed for a profit without the permission of the author and the University of Texas-Houston.
Translation: If you are a private individual using MacHTTP for your own amusement (not for profit or personal gain), or an educational or government institution using MacHTTP for publishing information freely available to the Internet, you can use it for free. If you're not covered by the first sentence, please contact the author to get the real scoop on using MacHTTP.
http://www.uth.tmc.edu/mac_info/machttp_info.html, the comp.infosystems.www
Usenet news group, and time permitting, from the author.The documentation covers just about everything there is to know about MacHTTP. So, please make sure you've read everything in the documentation, sample files, scripts, configuration file, and MacHTTP home page before you ask a question in e-mail.
Additional information about MacHTTP is available from
http://www.uth.tmc.edu/mac_info/machttp_info.html. This site
is the home of MacHTTP and always has the current version available for download.
Information on writing your own WWW documents (HTML) can be found at
http://www.ncsa.uiuc.edu/General/Internet/WWW/HTMLPrimer.html.
Information on URLs can be obtained from
http://www.ncsa.uiuc.edu/demoweb/url-primer.html.
Added support for a config file (MacHTTP.config) that specifies suffix mappings to TEXT, BINARY, or SCRIPT types.
Fixed bug where CERN's Mac WWW client caused MacHTTP to crash.
Improved text file transmission performance.
Added support for default home pages (Default.html) and error messages (Error.html).
Added Options menu to enable/disable versbose debugging mode.
Added version info to About box.
Adjusted idle proc used for synchronous MacTCP calls to only yield background time to other apps every 5 ticks, rather than every time called. Increases performance for small file requests.
Modified processing of HTTP "GET" command to parse the file name correctly. It should allow the server to work with HTTP2 clients that send data after the file name. The parsing routine does NOT currently handle translating special character escapes.
Increased memory partition to handle more connections.