Adds basic export capabilities.

papers/commands/__init__.py

@@ -1,6 +1,7 @@
 import add_cmd
 import add_library_cmd
 import import_cmd
+import export_cmd
 import init_cmd
 import list_cmd
 import open_cmd

papers/commands/export_cmd.py

@@ -0,0 +1,29 @@
+import sys
+
+import pybtex
+from pybtex.database import BibliographyData
+
+from .. import repo
+from .. import files
+
+
+def parser(subparsers, config):
+    parser = subparsers.add_parser('export',
+            help='export bibliography')
+    parser.add_argument('-f', '--bib-format', default='bibtex',
+            help="export format")
+    return parser
+
+
+def command(config, ui, bib_format):
+    """
+    :param bib_format       (in 'bibtex', 'yaml')
+    """
+    rp = repo.Repository.from_directory()
+    bib = BibliographyData()
+    for p in rp.all_papers():
+        bib.add_entry(p.citekey, p.bibentry)
+    try:
+        files.write_bibdata(bib, sys.stdout, bib_format)
+    except KeyError:
+        ui.error("Invalid output format: %s." % bib_format)

papers/files.py

@@ -27,11 +27,16 @@ except ImportError:
 _papersdir = None
 
 BIB_EXTENSIONS = ['.bib', '.bibyaml', '.bibml', '.yaml']
-FORMATS = {'bib': pybtex.database.input.bibtex,
+FORMATS_INPUT = {'bib': pybtex.database.input.bibtex,
                  'xml': pybtex.database.input.bibtexml,
                  'yml': pybtex.database.input.bibyaml,
                  'yaml': pybtex.database.input.bibyaml,
                  'bibyaml': pybtex.database.input.bibyaml}
+FORMATS_OUTPUT = {'bib': pybtex.database.output.bibtex,
+                 'xml': pybtex.database.output.bibtexml,
+                 'yml': pybtex.database.output.bibyaml,
+                 'yaml': pybtex.database.output.bibyaml,
+                 'bibyaml': pybtex.database.output.bibyaml}
 
 
 def clean_path(path):
@@ -112,10 +117,14 @@ def load_bibdata(filename, filepath):
     return load_externalbibfile(filepath)
 
 
+def write_bibdata(bib_data, file_, format_):
+    writer = FORMATS_OUTPUT[format_].Writer()
+    writer.write_stream(bib_data, file_)
+
+
 def save_bibdata(bib_data, filepath):
     with open(filepath, 'w') as f:
-        parser = pybtex.database.output.bibyaml.Writer()
+        write_bibdata(bib_data, f, 'yaml')
-        parser.write_stream(bib_data, f)
 
 
 def save_meta(meta_data, filepath):
@@ -131,7 +140,7 @@ def load_meta(filepath):
 def load_externalbibfile(fullbibpath):
     check_file(fullbibpath, fail=True)
     filename, ext = os.path.splitext(os.path.split(fullbibpath)[1])
-    if ext[1:] in FORMATS.keys():
+    if ext[1:] in FORMATS_INPUT.keys():
         with open(fullbibpath) as f:
             return parse_bibdata(f, ext[1:])
     else:
@@ -147,7 +156,7 @@ def parse_bibdata(content, format_):
     :content: stream
     :param format_: (bib|xml|yml)
     """
-    parser = FORMATS[format_].Parser()
+    parser = FORMATS_INPUT[format_].Parser()
     return parser.parse_stream(content)
 
 

papers/papers

@@ -14,6 +14,7 @@ cmds = collections.OrderedDict([
         ('add', commands.add_cmd),
         ('add_library', commands.add_library_cmd),
         ('import', commands.import_cmd),
+        ('export', commands.export_cmd),
         ('list', commands.list_cmd),
         ('edit', commands.edit_cmd),
         ('open', commands.open_cmd),

papers/ui.py

@@ -63,3 +63,6 @@ class UI:
         d = 0 if default in (True, 'y', 'yes') else 1
         return (True, False)[self.input_choice(['yes', 'no'], ['y', 'n'],
                                                default=d, question=question)]
+
+    def error(self, message):
+        self.print_("%s: %s" % (colored('error', 'red'), message))

tests/test_repo.py

@@ -4,7 +4,8 @@ import shutil
 import os
 
 import fixtures
-from papers.repo import Repository, _str_incr, _to_suffix, BIB_DIR, META_DIR
+from papers.repo import (Repository, _str_incr, _to_suffix, BIB_DIR, META_DIR,
+                         CiteKeyAlreadyExists)
 from papers.paper import PaperInRepo
 
 
@@ -65,9 +66,9 @@ class TestUpdatePaper(TestRepo):
         with self.assertRaises(ValueError):
             self.repo.update(fixtures.doe2013, old_citekey='zou')
 
-    def test_raises_value_error_on_existing_destination(self):
+    def test_error_on_existing_destination(self):
         self.repo.add_paper(fixtures.doe2013)
-        with self.assertRaises(ValueError):
+        with self.assertRaises(CiteKeyAlreadyExists):
             self.repo.update(fixtures.turing1950, old_citekey='Doe2013')
 
     def test_updates_same_key(self):