Reduce build log output and add "/Wall" build jobs.

Workaround for Arduino mDNS output noise using IPTABLES.
    See https://forum.arduino.cc/index.php?topic=469428.0
    See per1234/arduino-ci-script#1
    Arduino IDE adds a lot of noise caused by network traffic (mDNS?),
    because it's listening for network-attached devices.
    Firewall it in the TravisCI environment to cleanup logs.

Allow jobs with all warnings enabled to fail.
    This enables the build to occur, and review of warnings,
    without requiring these builds to be clean of warnings.
    Also, only outputs the error logs (not full build logs)
    for these build options.  This is a critical step
    towards getting to 100% warning-free builds, without
    interrupting current processes.

Author: henrygab

.travis.yml

@@ -1,3 +1,4 @@
+sudo: required
 language: c
 dist: xenial
 git:
@@ -8,10 +9,28 @@ env:
   global:
     - BSP_PATH="$HOME/.arduino15/packages/adafruit/hardware/nrf52"
   jobs:
-    # Split into one job per board (aka variant)
-    - VARIANT="feather52840"
-    - VARIANT="cplaynrf52840"
-    - VARIANT="feather52832"
+    # empty env required, else allow_failures will SILENTY IGNORE matching against env...
+    -
+
+jobs:
+  fast_finish: true
+  include:
+    - name: "Feather 52840"
+      env:  VARIANT="feather52840"
+    - name: "Feather 52840 (All warnings)"
+      env:  ALL_WARNINGS="true" VARIANT="feather52840"
+    - name: "Circuit Playground 52840"
+      env:  VARIANT="cplaynrf52840"
+    - name: "Circuit Playground 52840 (All warnings)"
+      env:  ALL_WARNINGS="true" VARIANT="cplaynrf52840"
+    - name: "Feather 52832"
+      env:  VARIANT="feather52832"
+    - name: "Feather 52832 (All warnings)"
+      env:  ALL_WARNINGS="true" VARIANT="feather52832"
+  allow_failures:
+    - env:  ALL_WARNINGS="true" VARIANT="feather52840"
+    - env:  ALL_WARNINGS="true" VARIANT="cplaynrf52840"
+    - env:  ALL_WARNINGS="true" VARIANT="feather52832"
 
 addons:
   apt:
@@ -34,6 +53,17 @@ install:
   - rm -r $BSP_PATH/*
   - ln -s $TRAVIS_BUILD_DIR $BSP_PATH/$BSP_VERSION
   - arduino --install-library "Adafruit NeoPixel","Adafruit NeoMatrix","Adafruit GFX Library","Adafruit SSD1306","MIDI Library","Adafruit ILI9341","Adafruit HX8357 Library"
+  # TODO: find way to filter out the noisy mDNS output from arduino IDE...
+  # See https://forum.arduino.cc/index.php?topic=469428.0
+  # See https://github.com/per1234/arduino-ci-script/issues/1
+  # Arduino IDE adds a lot of noise caused by network traffic (mDNS?)
+  # The following lines attempt to firewall it to prevent polluted error logs....
+  - sudo iptables -P INPUT DROP
+  - sudo iptables -P FORWARD DROP
+  - sudo iptables -P OUTPUT ACCEPT
+  - sudo iptables -A INPUT -i lo -j ACCEPT
+  - sudo iptables -A OUTPUT -o lo -j ACCEPT
+  - sudo iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
 
 before_script:
 

tools/build_all.py

@@ -8,6 +8,13 @@
 if "TRAVIS" in os.environ and os.environ["TRAVIS"] == "true":
     travis = True
 
+all_warnings = False
+if "ALL_WARNINGS" in os.environ and os.environ["ALL_WARNINGS"] == "true":
+    all_warnings = True
+
+ENV_VARIABLE_NAME = 'VARIANT'
+
+
 exit_status = 0
 success_count = 0
 fail_count = 0
@@ -21,6 +28,25 @@
     'feather52832': 'Feather nRF52832'
 }
 
+# STDERR receives output that starts with the following text, none of which should be considered a warning or error...
+output_to_ignore = (
+    'Picked up JAVA_TOOL_OPTIONS:',
+    'Loading configuration...',
+    'Initializing packages...',
+    'Preparing boards...',
+    'Verifying...',
+)
+
+def errorOutputFilter(line):
+    if len(line) == 0:
+        return False
+    if line.isspace(): # Note: empty string does not match here!
+        return False
+    if line.startswith(output_to_ignore): # alternatively, can trim() each line, but that would create lots of short-lived strings...
+        return False
+    # TODO: additional items to remove?
+    return True
+
 
 def build_examples(variant):
     global exit_status, success_count, fail_count, build_format, build_separator
@@ -33,18 +59,39 @@ def build_examples(variant):
     print(build_separator)
     subprocess.run("arduino --board adafruit:nrf52:{}:softdevice={},debug=l0 --save-prefs".format(variant, 's140v6' if variant != 'feather52832' else 's132v6'), shell=True,
                    stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+    
+    if all_warnings:
+        subprocess.run("arduino --pref 'compiler.warning_level=all' --save-prefs", shell=True,
+                       stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
 
     for sketch in glob.iglob('libraries/**/*.ino', recursive=True):
         start_time = time.monotonic()
 
         if os.path.exists(os.path.dirname(sketch) + '/.skip') or os.path.exists(os.path.dirname(sketch) + '/.skip.' + variant):
             success = "skipped"
         else:
-            build_result = subprocess.run("arduino --verify {}".format(sketch), shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+            # TODO - preferably, would have STDERR show up in **both** STDOUT and STDERR.
+            #        preferably, would use Python logging handler to get both distinct outputs and one merged output
+            #        for now, split STDERR when building with all warnings enabled, so can detect warning/error output.
+            if all_warnings:
+                build_result = subprocess.run("arduino --verify {}".format(sketch), shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+            else:
+                build_result = subprocess.run("arduino --verify {}".format(sketch), shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+
+            # get stderr into a form where len(warningLines) indicates a true warning was output to stderr
+            warningLines = [];
+            if all_warnings and build_result.stderr:
+                tmpWarningLines = build_result.stderr.decode("utf-8").splitlines()
+                warningLines = list(filter(errorOutputFilter, (tmpWarningLines)))
+
             if build_result.returncode != 0:
                 exit_status = build_result.returncode
                 success = "\033[31mfailed\033[0m   "
                 fail_count += 1
+            elif len(warningLines) != 0:
+                exit_status = -1
+                success = "\033[31mwarnings\033[0m "
+                fail_count += 1
             else:
                 success = "\033[32msucceeded\033[0m"
                 success_count += 1
@@ -58,14 +105,19 @@ def build_examples(variant):
 
         if build_result.returncode != 0:
             print(build_result.stdout.decode("utf-8"))
+            if (build_result.stderr):
+                print(build_result.stderr.decode("utf-8"))
+
+        if len(warningLines) != 0:
+            for line in warningLines:
+                print(line)
 
         if travis:
             print('travis_fold:end:build-{}\\r'.format(sketch))
 
 
 build_time = time.monotonic()
 
-ENV_VARIABLE_NAME = 'VARIANT'
 
 # build only one variant if the environment variable is specified
 if (ENV_VARIABLE_NAME in os.environ):
@@ -74,7 +126,7 @@ def build_examples(variant):
     if (variant in variants_dict):
         build_examples(variant)
     else:
-        print('\033[31failed\033[0m - invalid variant name "{}"'.format(variant))
+        print('\033[31INTERNAL ERR\033[0m - invalid variant name "{}"'.format(variant))
         fail_count += 1
         exit_status = -1