bug fixes & module rename -> brother_ql.backends.helpers

The rename was:
brother_ql.{printing,discovering} -> brother_ql.backends.helpers

brother_ql/backends/helpers.py

@@ -1,7 +1,10 @@
 #!/usr/bin/env python
 
 """
-The implementation of printing with the brother_ql package.
+Helpers for the subpackage brother_ql.backends
+
+* device discovery
+* printing
 """
 
 import logging, time
@@ -11,17 +14,28 @@ from brother_ql.reader import interpret_response
 
 logger = logging.getLogger(__name__)
 
-def send(instructions, printer_identifier=None, backend_name=None, blocking=True):
+def discover(backend_identifier='linux_kernel'):
+
+    be = backend_factory(backend_identifier)
+    list_available_devices = be['list_available_devices']
+    BrotherQLBackend       = be['backend_class']
+
+    available_devices = list_available_devices()
+    return available_devices
+
+def send(instructions, printer_identifier=None, backend_identifier=None, blocking=True):
     """
-    instructions: Bytes containing the instructions to be sent to the printer.
-    printer_identifier: String descriptor for the printer.
-    backend_name: Can enforce the use of a specific backend.
-    blocking: Boolean indicating whether the print() call should wait for completion.
+    Send instruction bytes to a printer.
+
+    :param bytes instructions: The instructions to be sent to the printer.
+    :param str printer_identifier: Identifier for the printer.
+    :param str backend_identifier: Can enforce the use of a specific backend.
+    :param bool blocking: Indicates whether the function call should block while waiting for the completion of the printing.
     """
 
     selected_backend = None
-    if backend_name:
-        selected_backend = backend_name
+    if backend_identifier:
+        selected_backend = backend_identifier
     else:
         try:
             selected_backend = guess_backend(printer_identifier)

brother_ql/brother_ql_print.py

@@ -7,8 +7,8 @@ Testing the packaged version of the Linux Kernel backend
 import argparse, logging, sys
 
 from brother_ql.backends import backend_factory, guess_backend, available_backends
-from brother_ql.printing import send
-from brother_ql.discovering import discover, pretty_print_discovered_devices
+from brother_ql.backends.helpers import discover, send
+from brother_ql.output_helpers import log_discovered_devices, textual_description_discovered_devices
 
 logger = logging.getLogger(__name__)
 
@@ -60,12 +60,11 @@ def main():
 
     # List any printers found, if explicitly asked to do so or if no identifier has been provided.
     if args.list_printers or not args.printer:
-        available_devices = discover(backend=selected_backend)
-        pretty_print_discovered_devices(available_devices)
+        available_devices = discover(backend_identifier=selected_backend)
+        log_discovered_devices(available_devices)
 
     if args.list_printers:
-        for printer in available_devices:
-            print(printer['identifier'])
+        print(textual_description_discovered_devices(available_devices))
         sys.exit(0)
 
     # Determine the identifier. Either selecting the explicitly stated one or using the first found device.
@@ -81,6 +80,6 @@ def main():
         identifier = args.printer
 
     # Finally, do the actual printing.
-    send(instructions=content, printer_identifier=identifier, backend_name=selected_backend, block=True)
+    send(instructions=content, printer_identifier=identifier, backend_identifier=selected_backend, blocking=True)
 
 if __name__ == "__main__": main()

brother_ql/discovering.py

@@ -1,30 +0,0 @@
-#!/usr/bin/env python
-
-"""
-Printer device discovery using the different brother_ql.backends
-"""
-
-import logging
-
-from brother_ql.backends import backend_factory, guess_backend, available_backends
-
-logger = logging.getLogger(__name__)
-
-def discover(backend_name='linux_kernel'):
-
-    be = backend_factory(selected_backend)
-    list_available_devices = be['list_available_devices']
-    BrotherQLBackend       = be['backend_class']
-
-    available_devices = list_available_devices()
-    return available_devices
-
-def pretty_print_discovered_devices(available_devices):
-    for ad in available_devices:
-        result = {'model': 'unknown'}
-        result.update(ad)
-        logger.info("  Found a label printer: {identifier}  (model: {model})".format(**result))
-
-        for printer in available_devices:
-            print(printer['identifier'])
-        sys.exit(0)

brother_ql/output_helpers.py

@@ -0,0 +1,37 @@
+import logging
+
+from brother_ql.devicedependent import label_type_specs
+from brother_ql.devicedependent import DIE_CUT_LABEL, ENDLESS_LABEL, ROUND_DIE_CUT_LABEL
+
+logger = logging.getLogger(__name__)
+
+def textual_label_description(labels_to_include):
+    output = "Supported label sizes:\n"
+    output = ""
+    fmt = " {label_size:9s} {dots_printable:14s} {label_descr:26s}\n"
+    output += fmt.format(label_size="Name", dots_printable="Printable px", label_descr="Description")
+    #output += fmt.format(label_size="", dots_printable="width x height", label_descr="")
+    for label_size in labels_to_include:
+        s = label_type_specs[label_size]
+        if s['kind'] in (DIE_CUT_LABEL, ROUND_DIE_CUT_LABEL):
+            dp_fmt = "{0:4d} x {1:4d}"
+        elif s['kind'] == ENDLESS_LABEL:
+            dp_fmt = "{0:4d}"
+        else:
+            dp_fmt = " - unknown - "
+        dots_printable = dp_fmt.format(*s['dots_printable'])
+        label_descr = s['name']
+        output += fmt.format(label_size=label_size, dots_printable=dots_printable, label_descr=label_descr)
+    return output
+
+def log_discovered_devices(available_devices, level=logging.INFO):
+    for ad in available_devices:
+        result = {'model': 'unknown'}
+        result.update(ad)
+        logger.log(level, "  Found a label printer: {identifier}  (model: {model})".format(**result))
+
+def textual_description_discovered_devices(available_devices):
+    output = ""
+    for ad in available_devices:
+        output += ad['identifier']
+    return output