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(How can I debug my tests?)
(How do I disable P2 mirrors?: add inputs from http://dev.eclipse.org/mhonarc/lists/tycho-user/msg05260.html)
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To cause your artifacts to be branded with the a build number, modify your manifests (<tt>MANIFEST.MF</tt>, <tt>feature.xml</tt>, etc.) to specify the version as <tt><em>X.Y.Z</em>.qualifier</tt>, and the corresponding <tt>pom.xml</tt> with <tt>X.Y.Z-SNAPSHOT</tt>.  Tycho will replace the <tt>qualifier</tt> and <em>SNAPSHOT</em> with the build timestamp (in UTC).
 
To cause your artifacts to be branded with the a build number, modify your manifests (<tt>MANIFEST.MF</tt>, <tt>feature.xml</tt>, etc.) to specify the version as <tt><em>X.Y.Z</em>.qualifier</tt>, and the corresponding <tt>pom.xml</tt> with <tt>X.Y.Z-SNAPSHOT</tt>.  Tycho will replace the <tt>qualifier</tt> and <em>SNAPSHOT</em> with the build timestamp (in UTC).
  
You can set the build qualifier to a custom value by setting the <tt>build.qualifier</tt> property.  For example:
+
You can set the build qualifier to a custom value by setting the <tt>forceContextQualifier</tt> property.  For example:
<pre>mvn -Dbuild.qualifier=M01 install</pre>
+
<pre>mvn -DforceContextQualifier=M01 install</pre>
 
You can also set the qualifier by configuring the tycho-packaging-plugin, using some format supported by Java's SimpleDateFormat:
 
You can also set the qualifier by configuring the tycho-packaging-plugin, using some format supported by Java's SimpleDateFormat:
 
<source lang="xml">
 
<source lang="xml">
Line 58: Line 58:
 
</plugin>
 
</plugin>
 
</source>
 
</source>
 
== How to build plugin-based products with platform-specific fragments? ==
 
 
First you need to configure all os/ws/arch environments for which you want to build. Example POM snippet:
 
 
<source lang="xml">
 
<plugin>
 
  <groupId>org.eclipse.tycho</groupId>
 
  <artifactId>target-platform-configuration</artifactId>
 
  <version>${tycho-version}</version>
 
  <configuration>
 
  <resolver>p2</resolver>
 
    <environments>
 
      <environment>
 
        <os>win32</os>
 
        <ws>win32</ws>
 
        <arch>x86</arch>
 
      </environment>
 
      <environment>
 
        <os>win32</os>
 
        <ws>win32</ws>
 
        <arch>x86_64</arch>
 
      </environment>
 
    </environments>
 
  </configuration>
 
</plugin>
 
</source>
 
 
for plugin-based (as opposed to feature-based) .product files, tycho needs additional os/ws/arch attributes for the fragments in the .product file which are not required by PDE.
 
 
Example product file snippet:
 
 
<source lang="xml">
 
<plugin id="org.eclipse.swt.win32.win32.x86" fragment="true" os="win32" ws="win32" arch="x86"/>
 
<plugin id="org.eclipse.swt.win32.win32.x86_64" fragment="true" os="win32" ws="win32" arch="x86_64"/>
 
</source>
 
  
 
== How to compile pre-processed source placed in a different directory? ==
 
== How to compile pre-processed source placed in a different directory? ==
  
Configure your pom.xml with something like the following:
+
In 0.13.0 you can configure your pom.xml with something like the following:
 
<pre>
 
<pre>
 
<build>
 
<build>
Line 111: Line 75:
 
</build>
 
</build>
 
</pre>
 
</pre>
 +
 +
But... "usePdeSourceRoots" was removed as part of 0.14.0 (see: [https://bugs.eclipse.org/bugs/show_bug.cgi?id=368083] and [http://git.eclipse.org/c/tycho/org.eclipse.tycho.git/commit/?id=ad06d9f10a7ca0dc380848a084ac25d4183c7c75]). 
 +
 +
In 0.16.0 it appears you you must use the build.properties.
  
 
== How do I include rootfiles? ==
 
== How do I include rootfiles? ==
  
Tycho provides partial support for [http://help.eclipse.org/indigo/index.jsp?topic=/org.eclipse.pde.doc.user/tasks/pde_rootfiles.htm PDE-style rootfiles]. Rootfiles are associated and installed with a feature. See [https://github.com/sonatype/sonatype-tycho/tree/master/tycho-its/projects/TYCHO465RootFiles the TYCHO465RootFiles test] for an example of using rootfiles.  
+
Tycho provides partial support for [http://help.eclipse.org/indigo/index.jsp?topic=/org.eclipse.pde.doc.user/tasks/pde_rootfiles.htm PDE-style rootfiles]. Rootfiles are associated and installed with a feature. See [http://git.eclipse.org/c/tycho/org.eclipse.tycho.git/tree/tycho-its/projects/TYCHO465RootFiles the TYCHO465RootFiles test] for an example of using rootfiles.  
  
A different approach is to use the ''maven-assembly-plugin'' to assemble a zip file. We do not have a worked example, but Kai Kreuzer documented his approach that was necessary prior to the introduction of rootfile support [http://kaikreuzer.blogspot.com/2010/12/building-p2-enabled-products-with-tycho.html].  
+
A different approach is to use the ''maven-assembly-plugin'' to assemble a zip file. We do not have a worked example, but Kai Kreuzer documented his approach that was necessary prior to the introduction of rootfile support [http://kaikreuzer.blogspot.com/2010/12/building-p2-enabled-products-with-tycho.html].
  
 
== How should I define the target platform of my tycho project? ==
 
== How should I define the target platform of my tycho project? ==
Line 159: Line 127:
  
 
Again, a <code>build.plugins.plugin.configuration.compilerArguments.properties</code> element can be used to reference an existing <code>org.eclipse.jdt.core.prefs</code> file (see [[Tycho/FAQ#How_to_configure_warning.2Ferror_settings_of_the_OSGi_compiler.3F|above]]).
 
Again, a <code>build.plugins.plugin.configuration.compilerArguments.properties</code> element can be used to reference an existing <code>org.eclipse.jdt.core.prefs</code> file (see [[Tycho/FAQ#How_to_configure_warning.2Ferror_settings_of_the_OSGi_compiler.3F|above]]).
 +
 +
= Packaging =
 +
 +
== How to generate Eclipse-SourceReferences MANIFEST header? ==
 +
 +
 +
See [http://eclipse.org/tycho/sitedocs/tycho-packaging-plugin/package-plugin-mojo.html#sourceReferences docs]. Example for git:
 +
 +
<pre>
 +
<properties>
 +
    <tycho.scmUrl>scm:git:https://git.eclipse.org/r/p/egit/egit.git</tycho.scmUrl>
 +
</properties>
 +
<plugin>
 +
  <groupId>org.eclipse.tycho</groupId>
 +
  <artifactId>tycho-packaging-plugin</artifactId>
 +
  <version>${tycho-version}</version>
 +
  <configuration>
 +
      <sourceReferences>
 +
        <generate>true</generate>
 +
      </sourceReferences>
 +
  </configuration>
 +
  <dependencies>
 +
      <dependency>
 +
        <groupId>org.eclipse.tycho.extras</groupId>
 +
        <artifactId>tycho-sourceref-jgit</artifactId>
 +
        <version>${tycho-extras-version}</version>
 +
      </dependency>
 +
  </dependencies>
 +
</plugin>
 +
</pre>
 +
 +
This will add the Eclipse-SourceReferences header including commit ID used for this build and tag (if present).
  
 
= Testing =
 
= Testing =
Line 284: Line 284:
 
== How to add a undeclared dependency?  (e.g., OSGi declarative service) ==
 
== How to add a undeclared dependency?  (e.g., OSGi declarative service) ==
  
Use the <tt> tycho-surefire-plugin</tt> <tt>&lt;dependencies&gt;</tt> section (see the [[Packaging Types#eclipse-test-plugin | eclipse-test-plugin]] packaging type for an example).
+
Use the <tt> tycho-surefire-plugin</tt> <tt>&lt;dependencies&gt;</tt> section (see the [[Tycho/Packaging_Types#eclipse-test-plugin | eclipse-test-plugin]] packaging type for an example).
  
 
== How to test OSGi declarative services? ==
 
== How to test OSGi declarative services? ==
Line 329: Line 329:
 
== How can I debug my tests? ==
 
== How can I debug my tests? ==
  
Tycho's surefire passes the contents of the <tt>tycho.testArgLine</tt> on the test-runner command line.  So you can cause your tests to pause for connection from a debugger with:
+
Add <tt>-DdebugPort=8000</tt> to your Maven commandline and attach a remote debug session.
  
<pre>
+
See the docs http://www.eclipse.org/tycho/sitedocs/tycho-surefire/tycho-surefire-plugin/test-mojo.html#debugPort
$ mvn -Dtycho.testArgLine="-Xdebug -agentlib:jdwp=transport=dt_socket,server=y,address=8000" verify
+
</pre>
+
Note that <tt>tycho.testArgLine</tt> is ignored if the test spec has an <tt>&lt;argLine/&gt;</tt> clause.
+
  
 
= Diagnosing Build Problems =
 
= Diagnosing Build Problems =
Line 351: Line 348:
  
 
Eclipse has a [http://help.eclipse.org/indigo/index.jsp?topic=%2Forg.eclipse.pde.doc.user%2Fguide%2Ftools%2Flaunchers%2Ftracing.htm platform tracing mechanism] which is switched on by using commandline option -debug and configured by putting a file named .options into the installation root.
 
Eclipse has a [http://help.eclipse.org/indigo/index.jsp?topic=%2Forg.eclipse.pde.doc.user%2Fguide%2Ftools%2Flaunchers%2Ftracing.htm platform tracing mechanism] which is switched on by using commandline option -debug and configured by putting a file named .options into the installation root.
You can enable this tracing mechanism for tycho test executions by running the build in debug mode using commandline option -X and putting a file .options inte the test project root.
+
You can enable this tracing mechanism for tycho test executions by running the build in debug mode using commandline option -X and putting a file .options into the test project root.
  
 
E.g. a file .options with content
 
E.g. a file .options with content
Line 360: Line 357:
 
</pre>
 
</pre>
  
will switch on equinox wiring tracing.
+
will switch on equinox wiring tracing. You may find it useful to use the "tee" command, since running the build in debug mode may generate a lot of output. An example of this syntax is:
 +
 
 +
<pre>
 +
cd tests/myPlugin
 +
mvn clean install -debug -X  | tee testout.txt
 +
</pre>
  
 
== Why is my app not working? ==
 
== Why is my app not working? ==
Line 375: Line 377:
 
* The [[PDE/FAQ | PDE FAQ]], particularly the section on [[PDE/FAQ#Build_and_Deployment_Errors | Build and Deployment Errors]].
 
* The [[PDE/FAQ | PDE FAQ]], particularly the section on [[PDE/FAQ#Build_and_Deployment_Errors | Build and Deployment Errors]].
 
* [[Where_Is_My_Bundle | Tips on diagnosing bundle load failures]].
 
* [[Where_Is_My_Bundle | Tips on diagnosing bundle load failures]].
 +
 +
== How do I disable P2 mirrors? ==
 +
 +
Often times eclipse.org redirects P2 repository requests to a misconfigured/broken/unavailable P2 mirror repository and builds fail because of that. To disable use of P2 mirrors and force all downloads to go directly to the main repository specify the following maven command line parameter
 +
 +
<pre>
 +
-Dtycho.disableP2Mirrors=true
 +
</pre>
 +
 +
It is also possible to set this property in a user/global settings.xml file. Here is settings.xml snippet:
 +
 +
  <profiles>
 +
    ...
 +
    <profile>
 +
      <id>p2</id>
 +
      <properties>
 +
        <tycho.disableP2Mirrors>true</tycho.disableP2Mirrors>
 +
      </properties>
 +
    </profile>
 +
  </profiles>
 +
 
 +
  <activeProfiles>
 +
    ...
 +
    <activeProfile>p2</activeProfile>
 +
  </activeProfiles>
 +
 +
Whether to use proxy or not is environment-specific configuration and as such does not belong in a pom.xml in the source tree.
  
 
= Documentation =
 
= Documentation =
Line 381: Line 410:
  
 
The documentation is available at:
 
The documentation is available at:
http://www.eclipse.org/tycho/sitedocs/tycho-surefire/
+
 
 +
http://www.eclipse.org/tycho/sitedocs/
 +
 
 +
and
 +
 
 +
http://www.eclipse.org/tycho/sitedocs-extras/
  
 
For more info see [[Tycho/Reference_Plugin_Docs]].
 
For more info see [[Tycho/Reference_Plugin_Docs]].
  
 
[[Category:Tycho|FAQ]][[Category:FAQ]]
 
[[Category:Tycho|FAQ]][[Category:FAQ]]

Revision as of 08:04, 28 January 2014

See also the Frequently asked Tycho questions on stackoverflow.com.

Compilation

How do I embed a configurable build version?

To cause your artifacts to be branded with the a build number, modify your manifests (MANIFEST.MF, feature.xml, etc.) to specify the version as X.Y.Z.qualifier, and the corresponding pom.xml with X.Y.Z-SNAPSHOT. Tycho will replace the qualifier and SNAPSHOT with the build timestamp (in UTC).

You can set the build qualifier to a custom value by setting the forceContextQualifier property. For example:

mvn -DforceContextQualifier=M01 install

You can also set the qualifier by configuring the tycho-packaging-plugin, using some format supported by Java's SimpleDateFormat:

<plugin>
  <groupId>org.eclipse.tycho</groupId>
  <artifactId>tycho-packaging-plugin</artifactId>
  <version>${tycho-version}</version>
  <configuration>
    <format>'myprefix_'yyyyMMddHHmm</format>
  </configuration>
</plugin>

Tycho does not directly support embedding the build identifier in resources. But some workarounds have been suggested in an email thread on tycho-user.

How to configure warning/error settings of the OSGi compiler?

To configure warnings:

<plugin>
  <groupId>org.eclipse.tycho</groupId>
  <artifactId>tycho-compiler-plugin</artifactId>
  <version>${tycho-version}</version>
  <configuration>
    <compilerArgument>-warn:[+|-]warning_tokens_separated_by_comma</compilerArgument>
  </configuration>
</plugin>

The available warning tokens are listed in the Eclipse help. Same applies for the

-err

argument for configuring errors.


Alternatively, if you have per-project JDT preferences, you may advise the compiler to use these:

<plugin>
  <groupId>org.eclipse.tycho</groupId>
  <artifactId>tycho-compiler-plugin</artifactId>
  <version>${tycho-version}</version>
  <configuration>
    <compilerArguments>
      <properties>${project.basedir}/.settings/org.eclipse.jdt.core.prefs</properties>
    </compilerArguments>
  </configuration>
</plugin>

How to compile pre-processed source placed in a different directory?

In 0.13.0 you can configure your pom.xml with something like the following:

<build>
   <plugin>
      <groupId>org.eclipse.tycho</groupId>
      <artifactId>tycho-compiler-plugin</artifactId>
      <version>${tycho-version}</version>
      <configuration>
         <source>${project.basedir}/YourNewSourceDirectory</source>
         <usePdeSourceRoots>false</usePdeSourceRoots>
      </configuration>
   </plugin>
</build>

But... "usePdeSourceRoots" was removed as part of 0.14.0 (see: [1] and [2]).

In 0.16.0 it appears you you must use the build.properties.

How do I include rootfiles?

Tycho provides partial support for PDE-style rootfiles. Rootfiles are associated and installed with a feature. See the TYCHO465RootFiles test for an example of using rootfiles.

A different approach is to use the maven-assembly-plugin to assemble a zip file. We do not have a worked example, but Kai Kreuzer documented his approach that was necessary prior to the introduction of rootfile support [3].

How should I define the target platform of my tycho project?

This question is answered here: Tycho/Target Platform


What other options does the Tycho compiler support?

Run this command to get a list of options for your version of Tycho:

mvn help:describe -Dplugin=org.eclipse.tycho:tycho-compiler-plugin -Ddetail

Or you can have a look at the Maven site for Tycho.

Can I use the Tycho compiler support in non-OSGi projects, too?

When compiling regular maven projects (e.g., packaging "jar") the plugin tycho-compiler-jdt can be used to tell maven to use the JDT compiler (aka "Eclipse Compiler for Java(TM)", "ecj") for compilation. This is useful to ensure that compilation in the IDE and on the build server show the same compiler messages, specifically JDT's annotation-based null analysis can be integrated into the build in this way.

Use the following snippet in your build.pluginManagement.plugins section:

<plugin>
	<!-- Use compiler plugin with tycho as the adapter to the JDT compiler. -->
	<artifactId>maven-compiler-plugin</artifactId>
	<configuration>
		<source>1.7</source>
		<target>1.7</target>
		<compilerId>jdt</compilerId>
		<compilerArgument>-err:nullAnnot,null</compilerArgument> <!-- insert your warn/err configuration here -->
	</configuration>
	<dependencies>
		<!-- This dependency provides the implementation of compiler "jdt": -->
		<dependency>
			<groupId>org.eclipse.tycho</groupId>
			<artifactId>tycho-compiler-jdt</artifactId>
			<version>${tycho-version}</version>
		</dependency>
	</dependencies>
</plugin>

Again, a build.plugins.plugin.configuration.compilerArguments.properties element can be used to reference an existing org.eclipse.jdt.core.prefs file (see above).

Packaging

How to generate Eclipse-SourceReferences MANIFEST header?

See docs. Example for git:

<properties>
    <tycho.scmUrl>scm:git:https://git.eclipse.org/r/p/egit/egit.git</tycho.scmUrl>
</properties>
<plugin>
   <groupId>org.eclipse.tycho</groupId>
   <artifactId>tycho-packaging-plugin</artifactId>
   <version>${tycho-version}</version>
   <configuration>
      <sourceReferences>
        <generate>true</generate>
      </sourceReferences>
   </configuration>
   <dependencies>
      <dependency>
        <groupId>org.eclipse.tycho.extras</groupId>
        <artifactId>tycho-sourceref-jgit</artifactId>
        <version>${tycho-extras-version}</version>
      </dependency>
   </dependencies>
</plugin>

This will add the Eclipse-SourceReferences header including commit ID used for this build and tag (if present).

Testing

How to configure HTTP proxy settings during test execution?

Two options:

Manually configure the proxy

<build>
  <plugins>
    <plugin>
      <groupId>org.eclipse.tycho</groupId>
      <artifactId>tycho-surefire-plugin</artifactId>
      <configuration>
        <argLine>-Dhttp.proxyHost=myproxy -Dhttp.proxyPort=1234</argLine>
      </configuration>
    </plugin>
  </plugins>
</build>

and disable the eclipse system proxy setting

    if (Platform.isRunning() && getProxyService() != null
      && getProxyService().isSystemProxiesEnabled()
      && !getProxyService().hasSystemProxies()) {
      // XXX e3.5/gtk.x86_64 activate manual proxy configuration which
      // defaults to Java system properties if system proxy support is
      // not available
     getProxyService().setSystemProxiesEnabled(false);
     getProxyService().setProxiesEnabled(true);
    }

- or -

Make sure the native org.eclipse.core.net.* fragment for your platform is included in the test runtime so eclipse will pick up proxy settings configured on OS level:

<build>
  <plugins>
    <plugin>
      <groupId>org.eclipse.tycho</groupId>
      <artifactId>tycho-surefire-plugin</artifactId>
      <configuration>
        <dependencies>
          <dependency>
            <type>p2-installable-unit</type>
            <artifactId>org.eclipse.core.net.[YOUR_PLATFORM]</artifactId>
            <version>[VERSION]</version>
          </dependency>
        </dependencies>
      </configuration>
    </plugin>
  </plugins>
</build>


How to use SWTBot or some UI tool for testing?

You need to configure the tycho-surefire-plugin to use the UI:
<build>
  <plugins>
    <plugin>
      <groupId>org.eclipse.tycho</groupId>
      <artifactId>tycho-surefire-plugin</artifactId>
      <configuration>
        <useUIHarness>true</useUIHarness>
        <useUIThread>false</useUIThread>
        <argLine>-Xms40m -Xmx512m</argLine>
      </configuration>
    </plugin>
  </plugins>
</build>

useUIHarness=true ensures the workbench is started before the tests are run. If your app requires a custom application class (viz the org.eclipse.core.runtime.applications extension point), you will likely need to configure the application.

You may wish to add --launcher.suppressErrors to the <appArgLine> element to suppress Eclipse error dialogs.

How do I add OS-specific flags?

Some OS's may require special flags (e.g., SWT on MacOS X). The easiest way is to use a Maven profile to configure a property. For example:

  <properties>
     <os-jvm-flags/> <!-- for the default case -->
  </properties>
 
  <build>
    <plugins>
      <plugin>
        <groupId>org.eclipse.tycho</groupId>
        <artifactId>tycho-surefire-plugin</artifactId>
        <version>${tycho-version}</version>
        <configuration>
          <useUIHarness>false</useUIHarness>
          <useUIThread>true</useUIThread>
          <argLine>-Xms40m -Xmx1G ${os-jvm-flags}</argLine>
        </configuration>
      </plugin>
    </plugins>
  </build>
 
  <profiles>
    <profile>
      <id>macosx-jvm-flags</id>
      <activation>
        <os><family>mac</family></os>
      </activation>
      <properties>
        <os-jvm-flags>-XstartOnFirstThread</os-jvm-flags>
      </properties>
    </profile>
  </profiles>

Alternatively you could configure the surefire plugins within a profile too.

How to add a undeclared dependency? (e.g., OSGi declarative service)

Use the tycho-surefire-plugin <dependencies> section (see the eclipse-test-plugin packaging type for an example).

How to test OSGi declarative services?

You need to add bundle org.eclipse.equinox.ds to the test runtime:

<plugin>
  <groupId>org.eclipse.tycho</groupId>
  <artifactId>tycho-surefire-plugin</artifactId>
  <configuration>
    <dependencies>
      <dependency>
        <type>p2-installable-unit</type>
        <artifactId>org.eclipse.equinox.ds</artifactId>
      </dependency>
    </dependencies>
  </configuration>
</plugin>


How do I enable assertions during testing?

Add an <argLine> to the tycho-surefire-plugin's configuration:

<build>
  <pluginManagement>
    <plugins>
      <plugin>
        <groupId>org.eclipse.tycho</groupId>
        <artifactId>tycho-surefire-plugin</artifactId>
        <version>${tycho-version}</version>
        <configuration>
          <argLine>-ea</argLine>
        </configuration>
      </plugin>
    </plugins>
  </pluginManagement>
</build>


How can I debug my tests?

Add -DdebugPort=8000 to your Maven commandline and attach a remote debug session.

See the docs http://www.eclipse.org/tycho/sitedocs/tycho-surefire/tycho-surefire-plugin/test-mojo.html#debugPort

Diagnosing Build Problems

What does Tycho's message "XXXX" mean?

See the Tycho Messages Explained page.


My build fails with a ClassCastException of a Tycho class. What is wrong?

ClassCastExceptions indicate that different Tycho versions are used in the same reactor. This is not supported. The problem typically occurs if some of the modules use the incorrect parent POM, e.g. an older version of the correct parent. Check the parent configuration in all modules of the reactor.

How to switch on eclipse tracing during test execution?

Eclipse has a platform tracing mechanism which is switched on by using commandline option -debug and configured by putting a file named .options into the installation root. You can enable this tracing mechanism for tycho test executions by running the build in debug mode using commandline option -X and putting a file .options into the test project root.

E.g. a file .options with content

org.eclipse.osgi/resolver/debug=true
org.eclipse.osgi/resolver/wiring=true

will switch on equinox wiring tracing. You may find it useful to use the "tee" command, since running the build in debug mode may generate a lot of output. An example of this syntax is:

cd tests/myPlugin
mvn clean install -debug -X  | tee testout.txt

Why is my app not working?

Many people post to tycho-user when they are encounter problems attempting to run their deployed applications, where the apps are missing icons, or throwing ClassNotFoundException and NoClassDefFoundError exceptions. Most of these problems are traced to errors in the projects' OSGi/p2 metadata. Some common issues are:

  • a bundle declares a runtime dependencies as optional, but the dependency is actually not optional;
  • the build.properties does not include some key directories or resources;
  • the class files are not being bundled into a library, but the classpath does not include ".".

Tycho is not the cause of these issues, but Tycho does help "discover" these issues.

Sources of help:

How do I disable P2 mirrors?

Often times eclipse.org redirects P2 repository requests to a misconfigured/broken/unavailable P2 mirror repository and builds fail because of that. To disable use of P2 mirrors and force all downloads to go directly to the main repository specify the following maven command line parameter

-Dtycho.disableP2Mirrors=true

It is also possible to set this property in a user/global settings.xml file. Here is settings.xml snippet:

 <profiles>
   ...
   <profile>
     <id>p2</id>
     <properties>
       <tycho.disableP2Mirrors>true</tycho.disableP2Mirrors>
     </properties>
   </profile>
 </profiles>
 
 <activeProfiles>
   ...
   <activeProfile>p2</activeProfile>
 </activeProfiles>

Whether to use proxy or not is environment-specific configuration and as such does not belong in a pom.xml in the source tree.

Documentation

Where can I find the Maven generated documentation for the Tycho plug-ins?

The documentation is available at:

http://www.eclipse.org/tycho/sitedocs/

and

http://www.eclipse.org/tycho/sitedocs-extras/

For more info see Tycho/Reference_Plugin_Docs.