Travis running tests on test servers (#272)

- README.md for adding test servers
 - Bash script for running tests on remote servers
 - Extend test_runner.py to flash using esptool.py
 - Python3.4 support. README.md update

tests/README.md

@@ -39,6 +39,12 @@ If not specified device `/dev/ttyUSB1` is used.
 
 `--no-flash` or `-n` - Do not flash the test firmware before running tests.
 
+`--flash` or `-f` - Flash device directly with esptool instead of using
+`make flash` command. Can be used to flash binaries without esp-open-rtos
+environment.
+
+`--flash-cmd` or `-c` - Flash command for esptool. Used together with `--flash`.
+
 `--list` or `-l` - Display list of the available test cases on the device.
 
 ### Example

tests/test_runner.py

@@ -44,9 +44,9 @@ def main():
     verbose = args.verbose
 
     if not args.no_flash:
-        flash_image(args.aport)
+        flash(args.aport, args)
         if args.type != 'solo':
-            flash_image(args.bport)
+            flash(args.bport, args)
 
     env = TestEnvironment(args.aport, TestEnvironment.A)
     env_b = None
@@ -279,11 +279,34 @@ def get_testdir():
     Return the 'tests' directory in the source tree
     (assuming the test_runner.py script is in that directory.
     """
-    res = os.path.dirname(__name__)
+    res = os.path.dirname(__file__)
     return "." if res == "" else res
 
 
-def flash_image(serial_port):
+def flash(serial_port, args):
+    if args.flash:
+        esptool_flash(serial_port, args.flash_cmd)
+    else:
+        make_flash(serial_port)
+
+
+def esptool_flash(serial_port, params):
+    env = dict(os.environ)
+    verbose_print("Flashing test image to %s..." % serial_port)
+    try:
+        stdout = sys.stdout if verbose else None
+        cmd = ["esptool.py", "-p", serial_port]
+        cmd.extend(params.split(' '))
+        cmd = [x for x in cmd if x]  # remove empty elements
+        subprocess.check_call(cmd, cwd=get_testdir(), stdout=stdout,
+                              stderr=subprocess.STDOUT, env=env)
+    except subprocess.CalledProcessError as e:
+        raise TestRunnerError("'esptool.py flash serial=%s' failed with exit code %d" %
+                              (serial_port, e.returncode))
+    verbose_print("Flashing successful.")
+
+
+def make_flash(serial_port):
     # Bit hacky: rather than calling esptool directly,
     # just use the Makefile flash target with the correct ESPPORT argument
     env = dict(os.environ)
@@ -329,6 +352,17 @@ def parse_args():
         action='store_true',
         default=False)
 
+    parser.add_argument(
+        '--flash', '-f',
+        help='Flash device directly with esptool',
+        action='store_true',
+        default=False)
+
+    parser.add_argument(
+        '--flash-cmd', '-c',
+        help='Flash command for esptool',
+        default='write_flash 0x2000 ./firmware/tests.bin')
+
     parser.add_argument(
         '--verbose', '-v',
         help='Verbose test runner debugging output',