initial work on metadata harvest bots

4 files changed, 197 insertions, 0 deletions

diff --git a/python/fatcat_tools/harvest/__init__.py b/python/fatcat_tools/harvest/__init__.py
new file mode 100644
index 00000000..85034f04
--- /dev/null
+++ b/python/fatcat_tools/harvest/__init__.py
@@ -0,0 +1,2 @@
+
+from .crossrefish import HarvestCrossrefWorker
diff --git a/python/fatcat_tools/harvest/crossrefish.py b/python/fatcat_tools/harvest/crossrefish.py
new file mode 100644
index 00000000..a88cedbd
--- /dev/null
+++ b/python/fatcat_tools/harvest/crossrefish.py
@@ -0,0 +1,39 @@
+
+"""
+Notes on crossref API:
+
+- from-index-date is the updated time
+- is-update can be false, to catch only new or only old works
+
+https://api.crossref.org/works?filter=from-index-date:2018-11-14,is-update:false&rows=2
+
+I think the design is going to have to be a cronjob or long-running job
+(with long sleeps) which publishes "success through" to a separate state
+queue, as simple YYYY-MM-DD strings.
+
+Within a day, will need to use a resumption token. Maybe should use a
+crossref library... meh.
+
+will want to have some mechanism in kafka consumer (pushing to fatcat) to group
+in batches as well. maybe even pass through as batches? or just use timeouts on
+iteration.
+"""
+
+from fatcat_tools.harvest.ingest_common import DoiApiHarvest
+
+class HarvestCrossrefWorker(DoiApiHarvest):
+
+    def __init__(self, kafka_hosts, produce_topic, state_topic, contact_email,
+            api_host_url="https://api.crossref.org/works",
+            is_update_filter=None,
+            start_date=None, end_date=None):
+        super().__init__(kafka_hosts=kafka_hosts,
+                         produce_topic=produce_topic,
+                         state_topic=state_topic,
+                         api_host_url=api_host_url,
+                         contact_email=contact_email,
+                         start_date=start_date,
+                         end_date=end_date)
+
+        self.is_update_filter = is_update_filter
+
diff --git a/python/fatcat_tools/harvest/datacite.py b/python/fatcat_tools/harvest/datacite.py
new file mode 100644
index 00000000..12860810
--- /dev/null
+++ b/python/fatcat_tools/harvest/datacite.py
@@ -0,0 +1,29 @@
+
+"""
+datacite has a REST API as well as OAI-PMH endpoint.
+
+have about 8 million 
+
+bulk export notes: https://github.com/datacite/datacite/issues/188
+
+fundamentally, very similar to crossref. don't have a scrape... maybe
+could/should use this script for that, and dump to JSON?
+"""
+
+from fatcat_tools.harvest.ingest_common import DoiApiHarvest
+
+class HarvestDataciteWorker(DoiApiHarvest):
+
+    def __init__(self, kafka_hosts, produce_topic, state_topic, contact_email,
+            api_host_url="https://api.datacite.org/works",
+            start_date=None, end_date=None):
+        super().__init__(kafka_hosts=kafka_hosts,
+                         produce_topic=produce_topic,
+                         state_topic=state_topic,
+                         api_host_url=api_host_url,
+                         contact_email=contact_email,
+                         start_date=start_date,
+                         end_date=end_date)
+
+        self.update_filter_name = "update"
+
diff --git a/python/fatcat_tools/harvest/ingest_common.py b/python/fatcat_tools/harvest/ingest_common.py
new file mode 100644
index 00000000..67ff3dc3
--- /dev/null
+++ b/python/fatcat_tools/harvest/ingest_common.py
@@ -0,0 +1,127 @@
+
+"""
+logic:
+- on start, fetch latest date from state feed
+- in a function (unit-testable), decide which dates to ingest
+- for each date needing update:
+    - start a loop for just that date, using resumption token for this query
+    - when done, publish to state feed, with immediate sync
+"""
+
+import re
+import sys
+import csv
+import json
+import requests
+import itertools
+import datetime
+from pykafka import KafkaClient
+
+from fatcat_tools.workers.worker_common import most_recent_message
+
+DATE_FMT = "%Y-%m-%d"
+
+class DoiApiHarvest:
+    """
+    This class supports core features for both the Crossref and Datacite REST
+    APIs for fetching updated metadata (the Datacite API seems to be moduled on
+    the Crossref API).
+
+    Implementations must provide the push results function.
+    """
+
+    def __init__(self, kafka_hosts, produce_topic, state_topic, api_host_url,
+            contact_email, start_date=None, end_date=None):
+        self.loop_sleep = 60*60 # how long to wait, in seconds, between date checks
+        self.api_batch_size = 50
+        self.api_host_url = api_host_url
+        self.produce_topic = produce_topic
+        self.state_topic = state_topic
+        self.contact_email = contact_email
+        self.kafka = KafkaClient(hosts=kafka_hosts, broker_version="1.0.0")
+        self.is_update_filter = None
+        self.update_filter_name = "index"
+
+        # these are both optional, and should be datetime.date
+        self.start_date = start_date
+        self.end_date = end_date
+
+    def get_latest_date(self):
+
+        state_topic = self.kafka.topics[self.state_topic]
+        latest = most_recent_message(state_topic)
+        if latest:
+            latest = datetime.datetime.strptime(latest.decode('utf-8'), DATE_FMT).date()
+        print("Latest date found: {}".format(latest))
+        return latest
+
+    def fetch_date(self, date):
+
+        state_topic = self.kafka.topics[self.state_topic]
+        produce_topic = self.kafka.topics[self.produce_topic]
+ 
+        date_str = date.strftime(DATE_FMT)
+        filter_param = 'from-{index}-date:{},until-{index}-date:{}'.format(
+            date_str, date_str, index=self.update_filter_name)
+        if self.is_update_filter is not None:
+            filter_param += ',is_update:{}'.format(bool(is_update))
+        params = {
+            'filter': filter_param,
+            'rows': self.api_batch_size,
+            'cursor': '*',
+        }
+        headers = {
+            'User-Agent': 'fatcat_tools/0.1.0 (https://fatcat.wiki; mailto:{}) python-requests'.format(self.contact_email),
+        }
+        count = 0
+        with produce_topic.get_producer() as producer:
+            while True:
+                http_resp = requests.get(self.api_host_url, params, headers=headers)
+                assert http_resp.status_code is 200
+                resp = http_resp.json()
+                items = resp['message']['items']
+                count += len(items)
+                print("... got {} ({} of {}) in {}".format(len(items), count,
+                    resp['message']['total-results']), http_resp.elapsed)
+                #print(json.dumps(resp))
+                for work in items:
+                    producer.produce(json.dumps(work).encode('utf-8'))
+                if len(items) < params['rows']:
+                    break
+                params['cursor'] = resp['message']['next-cursor']
+
+        # record our completion state
+        with state_topic.get_sync_producer() as producer:
+            producer.produce(date.strftime(DATE_FMT).encode('utf-8'))
+        
+
+    def run_once(self):
+        today_utc = datetime.datetime.utcnow().date()
+        if self.start_date is None:
+            self.start_date = self.get_latest_date()
+            if self.start_date: 
+                # if we are continuing, start day after last success
+                self.start_date = self.start_date + datetime.timedelta(days=1)
+        if self.start_date is None:
+            # bootstrap to yesterday (don't want to start on today until it's over)
+            self.start_date = datetime.datetime.utcnow().date()
+        if self.end_date is None:
+            # bootstrap to yesterday (don't want to start on today until it's over)
+            self.end_date = today_utc - datetime.timedelta(days=1)
+        print("Harvesting from {} through {}".format(self.start_date, self.end_date))
+        current = self.start_date
+        while current <= self.end_date:
+            print("Fetching DOIs updated on {} (UTC)".format(current))
+            self.fetch_date(current)
+            current += datetime.timedelta(days=1)
+        print("Crossref DOI ingest caught up through {}".format(self.end_date))
+        return self.end_date
+
+    def run_loop(self):
+        while True:
+            last = self.run_once()
+            self.start_date = last
+            self.end_date = None
+            print("Sleeping {} seconds...".format(self.loop_sleep))
+            time.sleep(self.loop_sleep())
+