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diff --git a/lib/webtool/doc/src/webtool_chapter.xml b/lib/webtool/doc/src/webtool_chapter.xml deleted file mode 100644 index 160a42f855..0000000000 --- a/lib/webtool/doc/src/webtool_chapter.xml +++ /dev/null @@ -1,246 +0,0 @@ -<?xml version="1.0" encoding="utf-8" ?> -<!DOCTYPE chapter SYSTEM "chapter.dtd"> - -<chapter> - <header> - <copyright> - <year>2001</year><year>2013</year> - <holder>Ericsson AB. All Rights Reserved.</holder> - </copyright> - <legalnotice> - Licensed under the Apache License, Version 2.0 (the "License"); - you may not use this file except in compliance with the License. - You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - - Unless required by applicable law or agreed to in writing, software - distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the License for the specific language governing permissions and - limitations under the License. - - </legalnotice> - - <title>WebTool User Guide</title> - <prepared></prepared> - <docno></docno> - <date></date> - <rev></rev> - <file>webtool_chapter.xml</file> - </header> - - <section> - <title>Introduction </title> - <p>WebTool provides an easy and efficient way to implement web - based tools with Erlang/OTP. WebTool configures and starts the - webserver and the various web based tools.</p> - <p>All tools that shall run under WebTool must have a *.tool - file in the code path or in its priv directory. When WebTool - starts it searches the code path for such files. For each - <c>ebin</c> directory in the path, the <c>priv</c> directory is - also searched. The *.tool files contain the configuration data - for each web based tool.</p> - </section> - - <section> - <title>Starting WebTool</title> - <p>Start WebTool by calling the function <c>webtool:start/0</c> or - <c>webtool:start/2</c>. If <c>webtool:start/0</c> is used the - start page of WebTool is available at - <em>http://localhost:8888/</em> or - <em>http://127.0.0.1:8888/</em>, and the directory containing - the root directory for the webserver, is assumed to be - <c><![CDATA[webtool-<vsn>/priv]]></c>.</p> - <p>Use <c>webtool:start/2</c> if the default path for the root - directory, port, ip-number or server name can not be used. See - the Reference Manual for <seealso marker="webtool">webtool</seealso> for more information.</p> - <p>WebTool, with the default configuration as in <c>start/0</c>, - can also be started with the <c>start_webtool</c> script which - is available in the <c>priv</c> directory of the WebTool - application. See the Reference Manual for <seealso marker="start_webtool">start_webtool</seealso> for further - information about this script. For Windows users, the batch file - <c>start_webtool.bat</c> can be used for the same purpose.</p> - </section> - - <section> - <title>Using WebTool</title> - <p>Start WebTool and point the browser to the corresponding URL. - At the top of the page there is a frame with a link named - <em>WebTool</em>. Click that link and a page where it is - possible to start the available tools will appear in the main - frame.</p> - </section> - - <section> - <title>Start a web based tool</title> - <p>Click on the link labeled <em>WebTool</em> in the topmost frame, - select the checkbox for each tool to start and - click on the button labeled <em>Start</em>. A link to each tool - that WebTool succeeded to start will appear in the topmost frame.</p> - </section> - - <section> - <title>Stop a web based tool</title> - <p>Click on the link labeled <em>WebTool</em> in the topmost - frame. Select <em>Stop Tools</em> in the left frame. Select the - checkbox for each tool to stop and click on the button labeled - <em>Stop</em>.</p> - </section> - - <section> - <title>Develop new web based tools</title> - <p>WebTool can be used as a framework when developing new web based - tools.</p> - <p>A web based tool running under WebTool will typically consist of - three parts.</p> - <list type="bulleted"> - <item>A *.tool file which defines how WebTool can find the tool's - configuration data</item> - <item>The Erlang code generating the web interface to the tool (HTML - code)</item> - <item>The tool itself.</item> - </list> - <p>In most cases it is a good idea to separate the code for - creation of the html-pages and the code for the logic. This - increases the readability of the code and the logic might be - possible to reuse.</p> - - <section> - <title>The *.tool file</title> - <p>When WebTool starts it searches the current path for - <c>*.tool</c> files to find all available tools. The *.tool - file contains a version identifier and a list of tuples which - is the configuration data. The version identifier specifies - the *.tool file version, i.e. not the version of - webtool. Currently the only valid version is "1.2" and the - only valid configuration tag is - <c>config_func</c>. <c>config_func</c> specifies which - function WebTool must call to get further configuration data - for the tool. This means that a *.tool file generally must - look like this:</p> - <code type="none"> - {version,"1.2"}. - [{config_func,{Module,Function,Arguments}}]. </code> - <p><c>Module</c> is the name of the module where the callback - function is defined. <c>Function</c> is the name of the - callback function, and <c>Arguments</c> is the list of - arguments to the callback function.</p> - </section> - - <section> - <title>The configuration function</title> - <p>The *.tool file points out a configuration function. This - function must return a list of configuration parameters (see - the Reference Manual for <seealso marker="webtool">webtool</seealso>).</p> - <p>The <c>web_data</c> parameter is mandatory and it specifies - the name of the tool and the link to the tool's start - page. All other parameters are optional.</p> - <p>If the tool requires any processes to run, the <c>start</c> - parameter specifies the function that WebTool must call in - order to start the process(es).</p> - <p>The <c>alias</c> parameters are passed directly on to the - webserver (INETS). The webserver has three ways to create - dynamic web pages CGI, Eval Scheme and Erl Scheme. All tools - running under WebTool must use Erl Scheme.</p> - <p>Erl Scheme tries to resemble plain CGI. The big difference is - that Erl Scheme can only execute Erlang code. The code will - furthermore be executed on the same instance as the webserver.</p> - <p>An URL which calls an Erlang function with Erl Scheme can have - the following syntax:</p> - <code type="none"><![CDATA[ -http://Servername:Port/ErlScriptAlias/Mod/Func<?QueryString> ]]></code> - <p>An <c>alias</c> parameter in the configuration function can be - an ErlScriptAlias as used in the above URL. The definition of - an ErlScriptAlias shall be like this:</p> - <p><c>{alias,{erl_alias,Path,[Modules]}}</c>, e.g.</p> - <p><c>{alias,{erl_alias,"/testtool",[helloworld]}}</c></p> - <p>The following URL will then cause a call to the function - helloworld:helloworld/2 (if WebTool is started with default - settings i.e. servername "localhost" and port 8888):</p> - <p><c>http://localhost:8888/testtool/helloworld/helloworld</c></p> - <p>Note that the module <c>helloworld</c> must be in the code - path of the node running WebTool.</p> - <p>Functions that are called via the Erl Scheme must take two - arguments, <c>Environment</c> and <c>Input</c>. - </p> - <list type="bulleted"> - <item><c>Environment</c> is a list of key/value tuples.</item> - <item><c>Input</c> is the part of the URL after the "?", i.e. the - part of the URL containing name-value pairs. If the page was - called with the URL: - <br></br> -<c><![CDATA[http://localhost:8888/testtool/helloworld/helloworld?input1=one&input2=two]]></c> <br></br> -<c>Input</c> will be the string - <c><![CDATA["input1=one&input2=two"]]></c>. In the module - <c>httpd</c> in the INETS application there is a function - <c>parse_query</c> which will parse such a string and return - a list of key-value tuples.</item> - </list> - <p>An <c>alias</c> parameter in the configuration function can - also be a normal path alias. This can e.g. be used to point - out a directory where HTML files are stored. The following - definition states that the URL - <c>http://localhost:8888/mytool_home/</c> really points to the - directory <c>/usr/local/otp/lib/myapp-1.0/priv</c>:</p> - <p><c>{alias,{"/mytool_home","/usr/local/otp/lib/myapp-1.0/priv"}}</c></p> - <p>See the INETS documentation, especially the module - <c>mod_esi</c>, for a more in depth coverage of the Erl Scheme.</p> - </section> - - <section> - <title>A small example</title> - <p>A Hello World example that uses Erl Scheme would look like - this. Note that this example does not have a process running - and thus does not need a <c>start</c> parameter in the - configuration function. - </p> - <p><em>helloworld.erl:</em></p> - <pre> - -module(helloworld). - -export([config_data/0]). - -export([helloworld/2]). - - config_data()-> - {testtool, - [{web_data,{"TestTool","/testtool/helloworld/helloworld"}}, - {alias,{erl_alias,"/testtool",[helloworld]}}]}. - - helloworld(_Env,_Input)-> - [header(),html_header(),helloworld_body(),html_end()]. - - header() -> - header("text/html"). - - header(MimeType) -> - "Content-type: " ++ MimeType ++ "\r\n\r\n". - - html_header() -> - "<HTML> - <HEAD> - <TITLE>Hello world Example </TITLE> - </HEAD>\n". - - helloworld_body()-> - "<BODY>Hello World</BODY>". - - html_end()-> - "</HTML>". - </pre> - <p>To use this example with WebTool a *.tool file must be created - and added to a directory in the current path, e.g. the same - directory as the compiled <c>helloworld.beam</c>.</p> - <p><em>testtool.tool:</em></p> - <code type="none"> - {version,"1.2"}. - [{config_func, {helloworld,config_data,[]}}]. - </code> - <p>When <c>helloworld.erl</c> is compiled, start WebTool by - calling the function <c>webtool:start()</c> and point your - browser to <em>http://localhost:8888/</em>. Select WebTool in - the topmost frame and start TestTool from the web page. Click - on the link labeled <em>TestTool</em> in the topmost frame.</p> - </section> - </section> -</chapter> - |