feat: guess output format from output file extension (#197)

guess output format based on output file extension

check for empty output file

default to .txt if no file extension provided

change default output format back to txt

add tests

update man page

fix default output format

directly return output dumper

use keys from dumpers in key error message

fix man pages

prevent output format from being overridden

use first dumper key as default format

update messages and formatting

update help message for format argument

specify list type in InvalidOutputFormat exception

make default output format more apparent

update messages

.scripts/tests-e2e.sh

@@ -128,6 +128,19 @@ assertSuccess "ls $HOME/kosmorro/export/document.pdf"
 assertSuccess "$KOSMORRO_COMMAND --position=\"50.5876;3.0624\" -d 2020-01-27 --format=pdf -o $HOME/kosmorro/export/document-no-graph.pdf --no-graph"
 assertSuccess "ls $HOME/kosmorro/export/document-no-graph.pdf"
 
+# If format argument is given, use it even if it conflicts with file extension
+assertSuccess "$KOSMORRO_COMMAND --position=\"50.5876;3.0624\" -d 2020-01-27 --format=json -o $HOME/kosmorro/export/txt-document.txt"
+assertSuccess "ls $HOME/kosmorro/export/txt-document.txt"
+
+assertSuccess "$KOSMORRO_COMMAND --position=\"50.5876;3.0624\" -d 2020-01-27 -o $HOME/kosmorro/export/txt-document.txt"
+assertSuccess "ls $HOME/kosmorro/export/txt-document.txt"
+
+assertSuccess "$KOSMORRO_COMMAND --position=\"50.5876;3.0624\" -d 2020-01-27 -o $HOME/kosmorro/export/json-document.json"
+assertSuccess "ls $HOME/kosmorro/export/json-document.json"
+
+assertSuccess "$KOSMORRO_COMMAND --position=\"50.5876;3.0624\" -d 2020-01-27 -o $HOME/kosmorro/export/pdf-document.pdf"
+assertSuccess "ls $HOME/kosmorro/export/pdf-document.pdf"
+
 # man page
 assertSuccess "man --pager=cat kosmorro"
 

_kosmorro/exceptions.py

@@ -39,6 +39,19 @@ class OutOfRangeDateError(RuntimeError):
         )
 
 
+class InvalidOutputFormatError(RuntimeError):
+    def __init__(self, output_format: str, accepted_extensions: [str]):
+        super().__init__()
+        self.output_format = output_format
+        self.accepted_extensions = accepted_extensions
+        self.msg = _(
+            "Invalid output format: {output_format}. Output file must end with: {accepted_extensions}"
+        ).format(
+            output_format=output_format,
+            accepted_extensions=", ".join(accepted_extensions),
+        )
+
+
 class CompileError(RuntimeError):
     def __init__(self, msg):
         super().__init__()

_kosmorro/locales/messages.pot

@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: kosmorro 0.10.1\n"
 "Report-Msgid-Bugs-To: EMAIL@ADDRESS\n"
-"POT-Creation-Date: 2021-08-10 20:23+0200\n"
+"POT-Creation-Date: 2021-08-24 17:06-0500\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -116,6 +116,12 @@ msgstr ""
 msgid "The date must be between {minimum_date} and {maximum_date}"
 msgstr ""
 
+#: _kosmorro/exceptions.py:47
+msgid ""
+"Invalid output format: {output_format}. Output file must end with: "
+"{accepted_extensions}"
+msgstr ""
+
 #: _kosmorro/geolocation.py:14
 #, python-format
 msgid "The given position (%s) is not valid."
@@ -125,104 +131,106 @@ msgstr ""
 msgid "The given Plus Code seems to be a short code, please provide a full code."
 msgstr ""
 
-#: _kosmorro/main.py:58
+#: _kosmorro/main.py:73
 msgid ""
 "Save the planet and paper!\n"
 "Consider printing your PDF document only if really necessary, and use the"
 " other side of the sheet."
 msgstr ""
 
-#: _kosmorro/main.py:67
+#: _kosmorro/main.py:82
 msgid ""
 "PDF output will not contain the ephemerides, because you didn't provide "
 "the observation coordinates."
 msgstr ""
 
-#: _kosmorro/main.py:112
+#: _kosmorro/main.py:132
 msgid "The file could not be saved in \"{path}\": {error}"
 msgstr ""
 
-#: _kosmorro/main.py:126
+#: _kosmorro/main.py:146
 msgid "Please provide a file path to export in this format (--output)."
 msgstr ""
 
-#: _kosmorro/main.py:159
+#: _kosmorro/main.py:179
 msgid "Moon phase can only be displayed between {min_date} and {max_date}"
 msgstr ""
 
-#: _kosmorro/main.py:198
+#: _kosmorro/main.py:228
 msgid "Running on Python {python_version} with Kosmorrolib v{kosmorrolib_version}"
 msgstr ""
 
-#: _kosmorro/main.py:208
+#: _kosmorro/main.py:238
 msgid "Do you really want to clear Kosmorro's cache? [yN] "
 msgstr ""
 
-#: _kosmorro/main.py:216
+#: _kosmorro/main.py:246
 msgid "Incorrect answer, cache not cleared."
 msgstr ""
 
-#: _kosmorro/main.py:226
+#: _kosmorro/main.py:256
 msgid ""
 "Compute the ephemerides and the events for a given date and a given "
 "position on Earth."
 msgstr ""
 
-#: _kosmorro/main.py:229
+#: _kosmorro/main.py:259
 msgid ""
 "By default, only the events will be computed for today ({date}).\n"
 "To compute also the ephemerides, latitude and longitude arguments are "
 "needed."
 msgstr ""
 
-#: _kosmorro/main.py:243
+#: _kosmorro/main.py:273
 msgid "Show the program version"
 msgstr ""
 
-#: _kosmorro/main.py:251
+#: _kosmorro/main.py:281
 msgid "Delete all the files from Kosmorro's cache."
 msgstr ""
 
-#: _kosmorro/main.py:259
-msgid "The format to output the information to"
+#: _kosmorro/main.py:289
+msgid ""
+"The format to output the information to. If not provided, the output "
+"format will be inferred from the file extension of the output file."
 msgstr ""
 
-#: _kosmorro/main.py:266
+#: _kosmorro/main.py:299
 msgid ""
 "The observer's position on Earth, in the \"{latitude},{longitude}\" "
 "format.Can also be set in the KOSMORRO_POSITION environment variable."
 msgstr ""
 
-#: _kosmorro/main.py:276
+#: _kosmorro/main.py:309
 msgid ""
 "The date for which the ephemerides must be calculated. Can be in the "
 "YYYY-MM-DD format or an interval in the \"[+-]YyMmDd\" format (with Y, M,"
 " and D numbers). Defaults to today ({default_date})."
 msgstr ""
 
-#: _kosmorro/main.py:287
+#: _kosmorro/main.py:320
 msgid ""
 "The timezone to display the hours in (e.g. 2 for UTC+2 or -3 for UTC-3). "
 "Can also be set in the KOSMORRO_TIMEZONE environment variable."
 msgstr ""
 
-#: _kosmorro/main.py:296
+#: _kosmorro/main.py:329
 msgid "Disable the colors in the console."
 msgstr ""
 
-#: _kosmorro/main.py:303
+#: _kosmorro/main.py:336
 msgid ""
 "A file to export the output to. If not given, the standard output is "
 "used. This argument is needed for PDF format."
 msgstr ""
 
-#: _kosmorro/main.py:312
+#: _kosmorro/main.py:345
 msgid ""
 "Do not generate a graph to represent the rise and set times in the PDF "
 "format."
 msgstr ""
 
-#: _kosmorro/main.py:320
+#: _kosmorro/main.py:353
 msgid "Show debugging messages"
 msgstr ""
 

_kosmorro/main.py

@@ -20,6 +20,7 @@ import argparse
 import locale
 import re
 import sys
+import os.path
 
 from kosmorrolib import Position, get_ephemerides, get_events, get_moon_phase
 from kosmorrolib.__version__ import __version__ as kosmorrolib_version
@@ -31,7 +32,11 @@ from . import dumper, environment, debug
 from .date import parse_date
 from .geolocation import get_position
 from .__version__ import __version__ as kosmorro_version
-from .exceptions import UnavailableFeatureError, OutOfRangeDateError as DateRangeError
+from .exceptions import (
+    InvalidOutputFormatError,
+    UnavailableFeatureError,
+    OutOfRangeDateError as DateRangeError,
+)
 from _kosmorro.i18n.utils import _, SHORT_DATE_FORMAT
 
 
@@ -53,6 +58,16 @@ def main():
 
     position = get_position(args.position) if args.position not in [None, ""] else None
 
+    # if output format is not specified, try to use output file extension as output format
+    if args.output is not None and output_format is None:
+        file_extension = os.path.splitext(args.output)[-1][1:].lower()
+        if file_extension:
+            output_format = file_extension
+
+    # default to .txt if output format was not given and output file did not have file extension
+    if output_format is None:
+        output_format = "txt"
+
     if output_format == "pdf":
         print(
             _(
@@ -88,6 +103,10 @@ def main():
             args.colors,
             args.show_graph,
         )
+    except InvalidOutputFormatError as error:
+        print(colored(error.msg, "red"))
+        debug.debug_print(error)
+        return 3
     except UnavailableFeatureError as error:
         print(colored(error.msg, "red"))
         debug.debug_print(error)
@@ -99,9 +118,10 @@ def main():
 
     if args.output is not None:
         try:
-            pdf_content = output.to_string()
-            with open(args.output, "wb") as output_file:
-                output_file.write(pdf_content)
+            file_content = output.to_string()
+            opening_mode = get_opening_mode(output_format)
+            with open(args.output, opening_mode) as output_file:
+                output_file.write(file_content)
         except UnavailableFeatureError as error:
             print(colored(error.msg, "red"))
             debug.debug_print(error)
@@ -168,25 +188,35 @@ def get_information(
 
     events_list = get_events(compute_date, timezone)
 
-    return get_dumpers()[output_format](
-        ephemerides=eph,
-        moon_phase=moon_phase,
-        events=events_list,
-        date=compute_date,
-        timezone=timezone,
-        with_colors=colors,
-        show_graph=show_graph,
-    )
+    try:
+        return get_dumpers()[output_format](
+            ephemerides=eph,
+            moon_phase=moon_phase,
+            events=events_list,
+            date=compute_date,
+            timezone=timezone,
+            with_colors=colors,
+            show_graph=show_graph,
+        )
+    except KeyError as error:
+        raise InvalidOutputFormatError(output_format, list(get_dumpers().keys()))
 
 
 def get_dumpers() -> {str: dumper.Dumper}:
     return {
-        "text": dumper.TextDumper,
+        "txt": dumper.TextDumper,
         "json": dumper.JsonDumper,
         "pdf": dumper.PdfDumper,
     }
 
 
+def get_opening_mode(format: str) -> str:
+    if format == "pdf":
+        return "wb"
+
+    return "w"
+
+
 def output_version() -> bool:
     python_version = "%d.%d.%d" % (
         sys.version_info[0],
@@ -254,9 +284,12 @@ def get_args(output_formats: [str]):
         "--format",
         "-f",
         type=str,
-        default=output_formats[0],
+        default=None,
         choices=output_formats,
-        help=_("The format to output the information to"),
+        help=_(
+            "The format to output the information to. If not provided, the output format "
+            "will be inferred from the file extension of the output file."
+        ),
     )
     parser.add_argument(
         "--position",

manpage/kosmorro.1.md

@@ -31,8 +31,8 @@
 `--output=`_OUTPUT_, `-o` _OUTPUT_  
     a file to export the output to; if not given, the standard output is used
 
-`--format=`_FORMAT_, `-f` _FORMAT_  
-    the format under which the information have to be output; one of the following: text, json, pdf
+`--format=`_FORMAT_, `-f` _FORMAT_ (optional)  
+    the format under which the information have to be output; one of the following: text, json, pdf. If no format is provided, the output format will be inferred from the extension of the output file
 
 `--no-graph`  
     present the ephemerides in a table instead of a graph; PDF output format only
@@ -68,7 +68,7 @@ kosmorro --latitude=50.5876 --longitude=3.0624 --date=2022-04-01
 Compute the ephemerides for Lille, France, on April 1st, 2022, and export them in a PDF document:
 
 ```
-kosmorro --latitude=50.5876 --longitude=3.0624 -date=2022-04-01 --format=pdf --output=file.pdf
+kosmorro --latitude=50.5876 --longitude=3.0624 -date=2022-04-01 --output=file.pdf
 ```
 
 ## AUTHOR