inject-slf4j: Move the SLF4J API logging bridges.

Problem/Solution

Update to move the SLF4J API logging bridges from dependencies of
`inject-sl4j` to dependencies of `inject-app` and `inject-server`
to allow other modules in the inject framework to be usable in
environments where having the bridges on the classpath can cause
issues.

JIRA Issues: CSL-6480

Differential Revision: https://phabricator.twitter.biz/D179652

CHANGELOG.md

@@ -11,6 +11,10 @@ All notable changes to this project will be documented in this file. Note that `
 
 ### Changed
 
+* inject-slf4j: Move the SLF4J API logging bridges from `inject-slf4j` to `inject-app`
+  and `inject-server`. This allows code in the inject framework to be mostly useful in
+  environments where having the bridges on the classpath causes issues. ``PHAB_ID=D179652``
+
 ### Fixed
 
 * finatra-http: Fail startup for incorrect Controller callback functions. Controller route callback

build.sbt

@@ -362,8 +362,12 @@ lazy val injectApp = (project in file("inject/inject-app"))
     name := "inject-app",
     moduleName := "inject-app",
     libraryDependencies ++= Seq(
+      "com.novocode" % "junit-interface" % "0.11" % Test,
       "com.twitter" %% "util-core" % versions.twLibVersion,
-      "com.novocode" % "junit-interface" % "0.11" % Test
+      "org.slf4j" % "jcl-over-slf4j" % versions.slf4j,
+      "org.slf4j" % "jul-to-slf4j" % versions.slf4j,
+      "org.slf4j" % "log4j-over-slf4j" % versions.slf4j,
+      "org.slf4j" % "slf4j-api" % versions.slf4j
     ),
     ScoverageKeys.coverageExcludedPackages := "<empty>;.*TypeConverter.*",
     publishArtifact in Test := true,
@@ -401,7 +405,11 @@ lazy val injectServer = (project in file("inject/inject-server"))
     libraryDependencies ++= Seq(
       "com.google.guava" % "guava" % versions.guava % Test,
       "com.twitter" %% "finagle-stats" % versions.twLibVersion,
-      "com.twitter" %% "twitter-server" % versions.twLibVersion
+      "com.twitter" %% "twitter-server" % versions.twLibVersion,
+      "org.slf4j" % "jcl-over-slf4j" % versions.slf4j,
+      "org.slf4j" % "jul-to-slf4j" % versions.slf4j,
+      "org.slf4j" % "log4j-over-slf4j" % versions.slf4j,
+      "org.slf4j" % "slf4j-api" % versions.slf4j
     ),
     publishArtifact in Test := true,
     mappings in (Test, packageBin) := {
@@ -432,9 +440,6 @@ lazy val injectSlf4j = (project in file("inject/inject-slf4j"))
       "com.fasterxml.jackson.core" % "jackson-annotations" % versions.jackson,
       "com.twitter" %% "finagle-core" % versions.twLibVersion,
       "com.twitter" %% "util-slf4j-api" % versions.twLibVersion,
-      "org.slf4j" % "jcl-over-slf4j" % versions.slf4j,
-      "org.slf4j" % "jul-to-slf4j" % versions.slf4j,
-      "org.slf4j" % "log4j-over-slf4j" % versions.slf4j,
       "org.slf4j" % "slf4j-api" % versions.slf4j)
   )
 

doc/src/sphinx/user-guide/logging/index.rst

@@ -3,8 +3,9 @@
 Introduction to Logging With Finatra
 ====================================
 
-Finatra uses the `SLF4J <http://www.slf4j.org/manual.html>`__ API for framework logging. By coupling the framework to only the
-`SLF4J <http://www.slf4j.org/manual.html>`__ API, application developers are free to choose their logging implementation.
+Finatra uses the `SLF4J <http://www.slf4j.org/manual.html>`__ API for framework logging. By coupling
+the framework to only the `SLF4J <http://www.slf4j.org/manual.html>`__ API, application developers
+are free to choose their actual logging implementation.
 
 .. admonition:: From the SLF4J documentation
 
@@ -13,15 +14,37 @@ Finatra uses the `SLF4J <http://www.slf4j.org/manual.html>`__ API for framework
     java.util.logging, Logback and log4j. SLF4J allows the end-user to
     plug in the desired logging framework at deployment time."
 
-`finatra/inject/inject-slf4j <https://github.com/twitter/finatra/tree/develop/inject/inject-slf4j>`__ provides transitively SLF4J bridges for the following logging providers:
+`finatra/inject/inject-app <https://github.com/twitter/finatra/tree/develop/inject/inject-app>`__
+and `finatra/inject/inject-server <https://github.com/twitter/finatra/tree/develop/inject/inject-server>`__
+transitively provide SLF4J bridges for the following logging providers:
 
 -  `Log4j <http://en.wikipedia.org/wiki/Log4j>`__
 -  `commons-logging <http://commons.apache.org/proper/commons-logging/>`__
--  `java.util.logging <http://docs.oracle.com/javase/7/docs/api/index.html?java/util/logging/package-summary.html>`__: there is a performance penalty for intercepting jul log messages, so `c.t.inject.server.TwitterServer` will install the `SLF4JBridgeHandler <http://www.slf4j.org/api/org/slf4j/bridge/SLF4JBridgeHandler.html>`__ which mitigates most of the performance penalty. Note, if you are not using the `c.t.inject.server.TwitterServer` or a subclass, e.g., you are building a command line application directly with `c.t.inject.app.App`, make sure the framework includes the `LoggingModule <https://github.com/twitter/finatra/blob/develop/inject/inject-modules/src/main/scala/com/twitter/inject/modules/LoggerModule.scala>`__ as a framework module.
+-  `java.util.logging <http://docs.oracle.com/javase/7/docs/api/index.html?java/util/logging/package-summary.html>`__:
+   there is a performance penalty for intercepting jul log messages, so `c.t.inject.server.TwitterServer`
+   will install the `SLF4JBridgeHandler <http://www.slf4j.org/api/org/slf4j/bridge/SLF4JBridgeHandler.html>`__
+   which mitigates most of the performance penalty.
 
-Since `SLF4J <http://www.slf4j.org/manual.html>`__ is an interface, it  requires an actual logging implementation. However, you should ensure that you **do not** end-up with *multiple* logging implementations on your classpath, e.g., you should not have multiple SLF4J bindings (`slf4j-nop`, `slf4j-log4j12`, `slf4j-jdk14`, etc.) nor a `java.util.logging` implementation, etc. on your classpath as these are all competing implementations and since classpath order is non-deterministic this will lead to unexpected logging behavior.
+.. tip::
 
-While there are several scala-wrappers for SLF4J, Finatra uses and exposes some additional features on top of the `TwitterUtil <https://twitter.github.io/util/>`__ `util-slf4j-api <https://github.com/twitter/util/tree/develop/util-slf4j-api>`__ project.
+   Note, if you are not using `c.t.inject.server.TwitterServer` or a subclass, e.g., you are
+   building a command line application directly with `c.t.inject.app.App`, you can include the
+   `LoggingModule <https://github.com/twitter/finatra/blob/develop/inject/inject-modules/src/main/scala/com/twitter/inject/modules/LoggerModule.scala>`__
+   to attempt installation the `SLF4JBridgeHandler <http://www.slf4j.org/api/org/slf4j/bridge/SLF4JBridgeHandler.html>`__.
+
+For more information on the SLF4J bridges see the SLF4J
+`Bridging legacy APIs <https://www.slf4j.org/legacy.html>`__ documentation.
+
+Since `SLF4J <http://www.slf4j.org/manual.html>`__ is an interface, it requires an actual logging
+implementation. However, you should ensure that you **do not** end-up with *multiple* logging
+implementations on your classpath, e.g., you should not have multiple SLF4J bindings (`slf4j-nop`,
+`slf4j-log4j12`, `slf4j-jdk14`, etc.) nor the `java.util.logging` implementation, etc. on your
+classpath as these are all competing implementations and since classpath order is non-deterministic
+this will lead to unexpected logging behavior.
+
+While there are several scala-wrappers for SLF4J, Finatra uses and exposes some additional features
+on top of the `TwitterUtil <https://twitter.github.io/util/>`__
+`util-slf4j-api <https://github.com/twitter/util/tree/develop/util-slf4j-api>`__ project.
 
 The main logging utility is the `c.t.inject.Logging <https://github.com/twitter/finatra/blob/develop/inject/inject-slf4j/src/main/scala/com/twitter/inject/Logging.scala>`__
 trait which can be mixed into any object or class:
@@ -38,8 +61,15 @@ trait which can be mixed into any object or class:
     }
 
 
-This trait is a wrapper with some added utility over the `c.t.util.logging.Logging <https://github.com/twitter/util/blob/develop/util-slf4j-api/src/main/scala/com/twitter/util/logging/Logging.scala>`__.
+This trait is a wrapper with some added utility over the
+`c.t.util.logging.Logging <https://github.com/twitter/util/blob/develop/util-slf4j-api/src/main/scala/com/twitter/util/logging/Logging.scala>`__.
+
+.. important::
 
-Scala users should prefer using the logging methods of the `c.t.inject.Logging <https://github.com/twitter/finatra/blob/develop/inject/inject-slf4j/src/main/scala/com/twitter/inject/Logging.scala>`__ trait (as opposed to directly accessing the Logger instance) as these methods use "call-by-name" parameters.
+    Scala users should prefer using the logging methods of the
+    `c.t.inject.Logging <https://github.com/twitter/finatra/blob/develop/inject/inject-slf4j/src/main/scala/com/twitter/inject/Logging.scala>`__
+    trait as opposed to directly accessing the underlying Logger instance in the Logging as these
+    methods use "call-by-name" parameters.
 
-For more information see the `scaladocs <https://twitter.github.io/finatra/scaladocs/index.html#com.twitter.inject.Logging>`__ for `c.t.inject.Logging` or the `util-slf4j-api README <https://github.com/twitter/util/blob/develop/util-slf4j-api/README.md>`__.
+For more information see the `c.t.inject.Logging` `scaladocs <https://twitter.github.io/finatra/scaladocs/index.html#com.twitter.inject.Logging>`__
+or the `util-slf4j-api README <https://github.com/twitter/util/blob/develop/util-slf4j-api/README.md>`__.

inject/inject-app/src/main/scala/BUILD

@@ -18,6 +18,9 @@ scala_library(
         "3rdparty/jvm/joda-time",
         "3rdparty/jvm/net/codingwell:scala-guice",
         "3rdparty/jvm/org/joda:joda-convert",
+        "3rdparty/jvm/org/slf4j:jcl-over-slf4j",
+        "3rdparty/jvm/org/slf4j:jul-to-slf4j",
+        "3rdparty/jvm/org/slf4j:log4j-over-slf4j",
         "3rdparty/jvm/org/slf4j:slf4j-api",
         "finatra/inject/inject-core/src/main/scala",
         "finatra/inject/inject-slf4j/src/main/scala",

inject/inject-server/src/main/scala/BUILD

@@ -11,6 +11,9 @@ scala_library(
         "3rdparty/jvm/com/google/inject/extensions:guice-assistedinject",
         "3rdparty/jvm/com/google/inject/extensions:guice-multibindings",
         "3rdparty/jvm/net/codingwell:scala-guice",
+        "3rdparty/jvm/org/slf4j:jcl-over-slf4j",
+        "3rdparty/jvm/org/slf4j:jul-to-slf4j",
+        "3rdparty/jvm/org/slf4j:log4j-over-slf4j",
         "3rdparty/jvm/org/slf4j:slf4j-api",
         "finagle/finagle-core/src/main/scala",
         "finagle/finagle-http/src/main/scala",

inject/inject-slf4j/src/main/scala/BUILD

@@ -9,20 +9,10 @@ scala_library(
     dependencies = [
         "3rdparty/jvm/com/fasterxml/jackson/core:jackson-annotations",
         "3rdparty/jvm/com/google/guava",
-        "3rdparty/jvm/org/slf4j:jcl-over-slf4j",
-        "3rdparty/jvm/org/slf4j:jul-to-slf4j",
-        "3rdparty/jvm/org/slf4j:log4j-over-slf4j",
-        "3rdparty/jvm/org/slf4j:slf4j-api",
         "finagle/finagle-core/src/main/scala",
         "util/util-core/src/main/scala",
         "util/util-slf4j-api/src/main/scala",
     ],
-    excludes = [
-        exclude(
-            org = "org.clapper",
-            name = "grizzled-slf4j",
-        ),
-    ],
     exports = [
         "3rdparty/jvm/com/fasterxml/jackson/core:jackson-annotations",
         "util/util-core/src/main/scala",