:green_heart: Update Travis CI's Doxygen.

Travis CI has Doxygen 1.7. We need 1.8 to generate our API
documentation. Get a static version and use it.
Always build API Documentation, but changed Doxygen configuration to
only print out errors in the documentation generation, so these can be
reviewed.

3 files changed, 42 insertions, 14 deletions

diff --git a/.travis.yml b/.travis.yml
index 6938033ce..1412390ab 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -21,8 +21,9 @@ addons:
   # Install dependencies for generating API documentation with doxygen
   apt:
     packages:
-      - doxygen
-      - doxygen-latex
+      # default doxygen 1.7 is too old, we install our own
+      #- doxygen
+      #- doxygen-latex
       - graphviz
       - ttf-liberation
 
@@ -75,6 +76,7 @@ matrix:
 cache:
   directories:
     - $HOME/.composer/cache
+    - $HOME/doxygen/doxygen-$DOXY_VER/bin
 
 
 
diff --git a/tests/travis/gen_apidocs.sh b/tests/travis/gen_apidocs.sh
index dc25347c6..248818117 100755
--- a/tests/travis/gen_apidocs.sh
+++ b/tests/travis/gen_apidocs.sh
@@ -34,25 +34,42 @@ if [[ "$TRAVIS_JOB_NUMBER" != "${TRAVIS_BUILD_NUMBER}.1" ]]; then
 	exit
 fi
 
-# @TODO get newer doxygen
-echo "Doxygen version 1.7 is too old for us :("
-doxygen --version
+# Get newer Doxygen
+#echo "Doxygen version 1.7 is too old for us :("
+#doxygen --version
 
-# Only build API documentation for master branch push
-if [[ "$TRAVIS_EVENT_TYPE" != "push" ]] || [[ "$TRAVIS_BRANCH" != "master" ]]; then
-	echo "Conditions not met to build API documentation."
-	echo "We are finished ..."
-	exit
+# Travis CI has an old Doxygen 1.7 build, so we fetch a recent static binary
+export DOXY_BINPATH=$HOME/doxygen/doxygen-$DOXY_VER/bin
+if [ ! -e "$DOXY_BINPATH/doxygen" ]; then
+	echo "Installing newer Doxygen $DOXY_VER ..."
+	mkdir -p $HOME/doxygen && cd $HOME/doxygen
+	wget -O - http://ftp.stack.nl/pub/users/dimitri/doxygen-$DOXY_VER.linux.bin.tar.gz | tar xz
+	export PATH=$PATH:$DOXY_BINPATH
 fi
+echo "Doxygen version"
+doxygen --version
 
-echo "Generating Doxygen API documentation for master ..."
-
+echo "Generating Doxygen API documentation ..."
 cd $TRAVIS_BUILD_DIR
 mkdir -p ./doc/html
-
-# Redirect stderr and stdout to log file and console
+# Redirect stderr and stdout to log file and console to be able to review documentation errors
 doxygen $DOXYFILE 2>&1 | tee ./doc/html/doxygen.log
 
+
+# There is no sane way yet, to prevent missuse of the push tokens in our workflow.
+# We would need a way to limit a token to only push to gh-pages or a way to prevent
+# manipulations to travis scripts which is not possible because we want it to run
+# for pull requests.
+# There are protected branches in GitHub, but they do not work for forced pushes.
+exit
+
+# Only continue for master branch pushes
+if [[ "$TRAVIS_EVENT_TYPE" != "push" ]] || [[ "$TRAVIS_BRANCH" != "master" ]]; then
+	echo "Conditions not met to build API documentation."
+	echo "We are finished ..."
+#	exit
+fi
+
 # Check if GitHub token is configured in Travis to be able to push to the repo
 if [ -z "$GHP_TOKEN" ]; then
 	echo "No GitHub token configured in Travis, can not deploy to gh-pages ..."
diff --git a/util/Doxyfile b/util/Doxyfile
index f6c0692ee..1bca6cbd4 100644
--- a/util/Doxyfile
+++ b/util/Doxyfile
@@ -23,3 +23,12 @@ ALIASES += "TODO=\todo"
 ALIASES += "BUG=\bug"
 ALIASES += "hooks=\xrefitem hooks \"Hooks\" \"Hooks List\""
 ALIASES += "HOOKS=\hooks"
+# Output
+QUIET = YES
+WARNINGS = YES
+# Dot tool config
+HAVE_DOT = YES
+DOT_IMAGE_FORMAT = svg
+INTERACTIVE_SVG = YES
+CLASS_GRAPH = YES
+COLLABORATION_GRAPH = NO