start supporting kafka importers

A nice feature would be some/any log output as to progress.

4 files changed, 36 insertions, 5 deletions

diff --git a/python/README_import.md b/python/README_import.md
index 6334dbc6..9ee24f8e 100644
--- a/python/README_import.md
+++ b/python/README_import.md
@@ -50,7 +50,7 @@ Usually tens of minutes on fast production machine.
 
 Usually 24 hours or so on fast production machine.
 
-    time xzcat /srv/fatcat/datasets/crossref-works.2018-09-05.json.xz | time parallel -j20 --round-robin --pipe ./fatcat_import.py crossref - /srv/fatcat/datasets/20180216.ISSN-to-ISSN-L.txt /srv/fatcat/datasets/release_ids.ia_munge_20180908.sqlite3
+    time xzcat /srv/fatcat/datasets/crossref-works.2018-09-05.json.xz | time parallel -j20 --round-robin --pipe ./fatcat_import.py crossref - /srv/fatcat/datasets/20180216.ISSN-to-ISSN-L.txt --extid-map-file /srv/fatcat/datasets/release_ids.ia_munge_20180908.sqlite3
 
 ## Matched
 
diff --git a/python/fatcat_import.py b/python/fatcat_import.py
index cdf04db1..555d4083 100755
--- a/python/fatcat_import.py
+++ b/python/fatcat_import.py
@@ -3,13 +3,18 @@
 import sys
 import argparse
 from fatcat_tools.importers import CrossrefImporter, OrcidImporter, \
-    IssnImporter, MatchedImporter, GrobidMetadataImporter
+    IssnImporter, MatchedImporter, GrobidMetadataImporter, make_kafka_consumer
 
 
 def run_crossref(args):
     fci = CrossrefImporter(args.host_url, args.issn_map_file,
         args.extid_map_file, create_containers=(not args.no_create_containers))
-    fci.process_batch(args.json_file, size=args.batch_size)
+    if args.kafka_mode:
+        consumer = make_kafka_consumer(
+            args.kafka_hosts, args.kafka_env, "crossref", "fatcat-import")
+        fci.process_batch(consumer, size=args.batch_size, decode_kafka=True)
+    else:
+        fci.process_batch(args.json_file, size=args.batch_size)
     fci.describe_run()
 
 def run_orcid(args):
@@ -41,6 +46,12 @@ def main():
     parser.add_argument('--host-url',
         default="http://localhost:9411/v0",
         help="connect to this host/port")
+    parser.add_argument('--kafka-hosts',
+        default="localhost:9092",
+        help="list of Kafka brokers (host/port) to use")
+    parser.add_argument('--kafka-env',
+        default="qa",
+        help="Kafka topic namespace to use (eg, prod, qa)")
     subparsers = parser.add_subparsers()
 
     sub_crossref = subparsers.add_parser('crossref')
@@ -51,7 +62,7 @@ def main():
     sub_crossref.add_argument('issn_map_file',
         help="ISSN to ISSN-L mapping file",
         default=None, type=argparse.FileType('r'))
-    sub_crossref.add_argument('extid_map_file',
+    sub_crossref.add_argument('--extid-map-file',
         help="DOI-to-other-identifiers sqlite3 database",
         default=None, type=str)
     sub_crossref.add_argument('--no-create-containers',
@@ -60,6 +71,9 @@ def main():
     sub_crossref.add_argument('--batch-size',
         help="size of batch to send",
         default=50, type=int)
+    sub_crossref.add_argument('--kafka-mode',
+        action='store_true',
+        help="consume from kafka topic (not stdin)")
 
     sub_orcid = subparsers.add_parser('orcid')
     sub_orcid.set_defaults(func=run_orcid)
diff --git a/python/fatcat_tools/importers/__init__.py b/python/fatcat_tools/importers/__init__.py
index 0f5fafb6..e6f081e5 100644
--- a/python/fatcat_tools/importers/__init__.py
+++ b/python/fatcat_tools/importers/__init__.py
@@ -1,5 +1,5 @@
 
-from .common import FatcatImporter
+from .common import FatcatImporter, make_kafka_consumer
 from .crossref import CrossrefImporter, CROSSREF_TYPE_MAP
 from .grobid_metadata import GrobidMetadataImporter
 from .issn import IssnImporter
diff --git a/python/fatcat_tools/importers/common.py b/python/fatcat_tools/importers/common.py
index 18594884..65976a21 100644
--- a/python/fatcat_tools/importers/common.py
+++ b/python/fatcat_tools/importers/common.py
@@ -5,16 +5,33 @@ import csv
 import json
 import itertools
 from collections import Counter
+import pykafka
 
 import fatcat_client
 from fatcat_client.rest import ApiException
 
+
 # from: https://docs.python.org/3/library/itertools.html
 def grouper(iterable, n, fillvalue=None):
     "Collect data into fixed-length chunks or blocks"
     args = [iter(iterable)] * n
     return itertools.zip_longest(*args, fillvalue=fillvalue)
 
+def make_kafka_consumer(hosts, env, topic_suffix, group):
+    topic_name = "fatcat-{}.{}".format(env, topic_suffix).encode('utf-8')
+    client = pykafka.KafkaClient(hosts=hosts, broker_version="1.0.0")
+    consume_topic = client.topics[topic_name]
+    print("Consuming from kafka topic {}, group {}".format(topic_name, group))
+
+    consumer = consume_topic.get_balanced_consumer(
+        consumer_group=group.encode('utf-8'),
+        managed=True,
+        auto_commit_enable=True,
+        auto_commit_interval_ms=30000, # 30 seconds
+        compacted_topic=True,
+    )
+    return consumer
+
 class FatcatImporter:
     """
     Base class for fatcat importers