Include required plugins automatically seem not consider already added capabilties

[laeubi]

If I use the "Include required plugins automatically" option I noticed that it does seem to add more than required in some situations.

For example assume a product hat has slf4j.api and two slf4j provider implementations are in the target then PDE adds another slf4j provider even if one was already chosen in the product, I noticed that when working on

• Create an SLF4j provider implementation for the Equinox Log eclipse-equinox/equinox#740

with the product here:

<?xml version="1.0" encoding="UTF-8"?>
<?pde version="3.5"?>

<product uid="testslf4j" version="1.0.0.qualifier" type="bundles" includeLaunchers="true" autoIncludeRequirements="false">

   <configIni use="default">
   </configIni>

   <launcherArgs>
      <programArgs>-console
      </programArgs>
      <vmArgs>-Declipse.ignoreApp=true
-Dosgi.noShutdown=true
      </vmArgs>
      <vmArgsMac>-XstartOnFirstThread -Dorg.eclipse.swt.internal.carbon.smallFonts
      </vmArgsMac>
   </launcherArgs>

   <launcher>
      <win useIco="false">
         <bmp/>
      </win>
   </launcher>

   <vm>
   </vm>

   <plugins>
      <plugin id="my.logging.bundle"/>
      <plugin id="org.apache.aries.spifly.dynamic.bundle"/>
      <plugin id="org.apache.felix.gogo.command"/>
      <plugin id="org.apache.felix.gogo.runtime"/>
      <plugin id="org.apache.felix.gogo.shell"/>
      <plugin id="org.apache.felix.scr"/>
      <plugin id="org.eclipse.equinox.common"/>
      <plugin id="org.eclipse.equinox.console"/>
      <plugin id="org.eclipse.osgi"/>
      <plugin id="org.objectweb.asm"/>
      <plugin id="org.objectweb.asm.commons"/>
      <plugin id="org.objectweb.asm.tree"/>
      <plugin id="org.objectweb.asm.tree.analysis"/>
      <plugin id="org.objectweb.asm.util"/>
      <plugin id="org.osgi.service.component"/>
      <plugin id="org.osgi.util.function"/>
      <plugin id="org.osgi.util.promise"/>
      <plugin id="slf4j.api"/>
   </plugins>

   <configurations>
      <plugin id="org.apache.aries.spifly.dynamic.bundle" autoStart="true" startLevel="1" />
      <plugin id="org.apache.felix.scr" autoStart="true" startLevel="2" />
      <plugin id="org.eclipse.core.runtime" autoStart="true" startLevel="0" />
      <plugin id="org.eclipse.equinox.common" autoStart="true" startLevel="2" />
      <plugin id="org.eclipse.equinox.event" autoStart="true" startLevel="2" />
      <plugin id="org.eclipse.equinox.simpleconfigurator" autoStart="true" startLevel="1" />
   </configurations>

</product>

The product itself is "complete" so works with autoIncludeRequirements="false" already, no missing requirements are reported when validated. If one starts the product it is getting the expected message:

SLF4J(W): No SLF4J providers were found.
SLF4J(W): Defaulting to no-operation (NOP) logger implementation
SLF4J(W): See https://www.slf4j.org/codes.html#noProviders for further details.

Now I add <plugin id="org.eclipse.equinox.slf4j"/> and logging works and I get:

id	State       Bundle
7	ACTIVE      org.eclipse.equinox.slf4j_1.0.0.qualifier
17	RESOLVED    slf4j.api_2.0.16

if now one activates autoIncludeRequirements="true" one suddenly gets

id	State       Bundle
6	RESOLVED    slf4j.simple_2.0.16
8	ACTIVE      org.eclipse.equinox.slf4j_1.0.0.qualifier
18	RESOLVED    slf4j.api_2.0.16

@HannesWell can you take a look as this feature is extremely useful but might confusing in some situations like this.

[HannesWell]

This is probably because DependencyManager considers all kind of requirements:

eclipse.pde/ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/DependencyManager.java

Line 199 in 975f72b

List<BundleWire> requiredWires = wiring.getRequiredWires(null);

And IIRC the slf4j.api bundle has a (OSGi) requirement to all it's providers through the Service-Loader mediator configuration.

In this specific case the life-line that prevents a real problem is that the Aries SPI-fly service-loader mediator only considers bundles in state active, which isn't usually the case (like in your example) as long as one has not configured it as auto-started in the product configuration (at least in my use-cases this was the case).

But of course in general it would be cleaner to not have the other providers in the product at all. I wanted to add meant to filter the considered required-wires so that the DependencyManager can be used in more places in PDE.
Then the service-loader requirements could be filtered too.