From 417f1ea363baa334b260a84c0ca12b3779f02cf8 Mon Sep 17 00:00:00 2001
From: Ian Ward <ian@excess.org>
Date: Fri, 6 Jan 2017 13:14:14 -0500
Subject: [PATCH] [#3390] datastore: dump TSV with format=tsv

---
 ckanext/datastore/controller.py | 36 ++++++++++++++++++++++++---------
 ckanext/datastore/plugin.py     |  2 +-
 doc/maintaining/datastore.rst   |  4 +++-
 3 files changed, 31 insertions(+), 11 deletions(-)

diff --git a/ckanext/datastore/controller.py b/ckanext/datastore/controller.py
index 9e5bdec40f3..81d3759b025 100644
--- a/ckanext/datastore/controller.py
+++ b/ckanext/datastore/controller.py
@@ -21,12 +21,12 @@
 boolean_validator = get_validator('boolean_validator')
 
 UTF8_BOM = u'\uFEFF'.encode('utf-8')
-
+DUMP_FORMATS = 'csv', 'tsv'
 PAGINATE_BY = 10000
 
 
 class DatastoreController(BaseController):
-    def dump_csv(self, resource_id):
+    def dump(self, resource_id):
         try:
             offset = int_validator(request.GET.get('offset', 0), {})
         except Invalid as e:
@@ -36,6 +36,30 @@ def dump_csv(self, resource_id):
         except Invalid as e:
             abort(400, u'limit: ' + e.error)
         bom = boolean_validator(request.GET.get('bom'), {})
+        fmt = request.GET.get('format', 'csv')
+
+        def start_writer():
+            if fmt == 'csv':
+                response.headers['Content-Type'] = 'text/csv; charset=utf-8'
+                response.headers['Content-disposition'] = (
+                    'attachment; filename="{name}.csv"'.format(
+                        name=resource_id))
+                wr = csv.writer(response, encoding='utf-8')
+            elif fmt == 'tsv':
+                response.headers['Content-Type'] = (
+                    'text/tab-separated-values; charset=utf-8')
+                response.headers['Content-disposition'] = (
+                    'attachment; filename="{name}.tsv"'.format(
+                        name=resource_id))
+                wr = csv.writer(
+                    response, encoding='utf-8', dialect=csv.excel_tab)
+            else:
+                abort(400,
+                    _(u'format: must be one of %s') % u', '.join(DUMP_FORMATS))
+
+            if bom:
+                response.write(UTF8_BOM)
+            return wr
 
         wr = None
         while True:
@@ -54,15 +78,9 @@ def dump_csv(self, resource_id):
                 abort(404, _('DataStore resource not found'))
 
             if not wr:
-                response.headers['Content-Type'] = 'text/csv; charset=utf-8'
-                response.headers['Content-disposition'] = (
-                    'attachment; filename="{name}.csv"'.format(
-                        name=resource_id))
-                wr = csv.writer(response, encoding='utf-8')
+                wr = start_writer()
 
                 header = [x['id'] for x in result['fields']]
-                if bom:
-                    response.write(UTF8_BOM)
                 wr.writerow(header)
 
             for record in result['records']:
diff --git a/ckanext/datastore/plugin.py b/ckanext/datastore/plugin.py
index 4b725fed813..073ffcee214 100644
--- a/ckanext/datastore/plugin.py
+++ b/ckanext/datastore/plugin.py
@@ -248,7 +248,7 @@ def get_auth_functions(self):
     def before_map(self, m):
         m.connect('/datastore/dump/{resource_id}',
                   controller='ckanext.datastore.controller:DatastoreController',
-                  action='dump_csv')
+                  action='dump')
         return m
 
     def before_show(self, resource_dict):
diff --git a/doc/maintaining/datastore.rst b/doc/maintaining/datastore.rst
index 8878d41ef6c..a19294f6c9b 100644
--- a/doc/maintaining/datastore.rst
+++ b/doc/maintaining/datastore.rst
@@ -280,7 +280,9 @@ Download resource as CSV
 
 A DataStore resource can be downloaded in the `CSV`_ file format from ``{CKAN-URL}/datastore/dump/{RESOURCE-ID}``.
 
-For an Excel-compatible CSV file use ``{CKAN-URL}/datastore/dump/{RESOURCE-ID}&bom=true``
+For an Excel-compatible CSV file use ``{CKAN-URL}/datastore/dump/{RESOURCE-ID}?bom=true``.
+
+For tab-separated values use ``{CKAN-URL}/datastore/dump/{RESOURCE-ID}?format=tsv``.
 
 .. _CSV: https://en.wikipedia.org/wiki/Comma-separated_values