support for saving echoprint fingerprints of songs

server/djrandom/fingerprint/fingerprint.py

+import os
+import optparse
+import logging
+import subprocess
+import time
+import traceback
+from djrandom import daemonize
+from djrandom import utils
+from djrandom.model.mp3 import MP3
+from djrandom.database import Session, init_db
+
+log = logging.getLogger(__name__)
+
+
+class Fingerprinter(object):
+
+    def __init__(self, codegen_path):
+        self.codegen_path = codegen_path
+
+    def process(self, mp3):
+        pipe = subprocess.Popen(
+            [self.codegen_path, mp3.path, '10', '30'],
+            close_fds=False,
+            stdout=subprocess.PIPE)
+        fp_json = pipe.communicate()[0]
+        if fp_json:
+            # Remove the square brackets that make fp_json an array.
+            # (Ugly Hack!)
+            mp3.echoprint_fp = fp_json[2:-2]
+
+    def compute_fingerprints(self, run_once):
+        """Compute fingerprints of new files."""
+        while True:
+            mp3 = MP3.query.filter(MP3.echoprint_fp.null()
+                                   ).limit(1).first()
+            if not mp3:
+                if run_once:
+                    break
+                Session.remove()
+                self.idx.commit()
+                time.sleep(60)
+                continue
+            log.info('fingerprinting %s' % mp3.sha1)
+            try:
+                self.process(mp3)
+            except Exception, e:
+                log.error(traceback.format_exc())
+            Session.add(mp3)
+            Session.commit()
+
+
+def run_fingerprinter(db_url, codegen_path, run_once):
+    init_db(db_url)
+    scanner = Fingerprinter(codegen_path)
+    scanner.compute_fingerprints(run_once)
+
+
+def main():
+    parser = optparse.OptionParser()
+    parser.add_option('--once', action='store_true')
+    parser.add_option('--codegen_path',
+                      default='/usr/local/bin/echoprint-codegen')
+    parser.add_option('--db_url')
+    daemonize.add_standard_options(parser)
+    utils.read_config_defaults(
+        parser, os.getenv('DJRANDOM_CONF', '/etc/djrandom.conf'))
+    opts, args = parser.parse_args()
+    if not opts.db_url:
+        parser.error('Must provide --db_url')
+    if args:
+        parser.error('Too many arguments')
+
+    if opts.once:
+        opts.foreground = True
+
+    daemonize.daemonize(opts, run_fingerprinter,
+                        (opts.db_url, opts.codegen_path, opts.once))
+
+
+if __name__ == '__main__':
+    main()

server/djrandom/model/mp3.py

 import random
+from sqlalchemy.orm import deferred
 from sqlalchemy import *
 from datetime import datetime, timedelta
 from djrandom.database import Base, Session
@@ -23,6 +24,7 @@ class MP3(Base):
     genre = Column(Unicode(64))
     uploaded_at = Column(DateTime())
     play_count = Column(Integer(), default=0)
+    echoprint_fp = deferred(Column(Text()))
 
     def __init__(self, **kw):
         for k, v in kw.items():

server/setup.py

@@ -17,6 +17,7 @@ setup(
     "console_scripts": [
       "djrandom-receiver = djrandom.receiver.receiver:main",
       "djrandom-scanner = djrandom.scanner.scanner:main",
+      "djrandom-fingerprinter = djrandom.fingerprint.fingerprint:main",
       "djrandom-streamer = djrandom.stream.stream:main",
       "djrandom-frontend = djrandom.frontend.frontend:main",
       "djrandom-update-markov = djrandom.model.markov:main",