1 files changed, 58 insertions, 0 deletions
diff --git a/backend/tolData/enwiki/genDumpIndexDb.py b/backend/tolData/enwiki/genDumpIndexDb.py
new file mode 100755
index 0000000..3955885
--- /dev/null
+++ b/backend/tolData/enwiki/genDumpIndexDb.py
@@ -0,0 +1,58 @@
+#!/usr/bin/python3
+
+import sys, os, re
+import bz2
+import sqlite3
+
+usageInfo = f"""
+Usage: {sys.argv[0]}
+
+Adds data from the wiki dump index-file into a database.
+"""
+if len(sys.argv) > 1:
+	print(usageInfo, file=sys.stderr)
+	sys.exit(1)
+
+indexFile = "enwiki-20220501-pages-articles-multistream-index.txt.bz2" # Had about 22e6 lines
+indexDb = "dumpIndex.db"
+
+if os.path.exists(indexDb):
+	raise Exception(f"ERROR: Existing {indexDb}")
+print("Creating database")
+dbCon = sqlite3.connect(indexDb)
+dbCur = dbCon.cursor()
+dbCur.execute("CREATE TABLE offsets (title TEXT PRIMARY KEY, id INT UNIQUE, offset INT, next_offset INT)")
+
+print("Iterating through index file")
+lineRegex = re.compile(r"([^:]+):([^:]+):(.*)")
+lastOffset = 0
+lineNum = 0
+entriesToAdd = []
+with bz2.open(indexFile, mode='rt') as file:
+	for line in file:
+		lineNum += 1
+		if lineNum % 1e5 == 0:
+			print(f"At line {lineNum}")
+		#
+		match = lineRegex.fullmatch(line.rstrip())
+		(offset, pageId, title) = match.group(1,2,3)
+		offset = int(offset)
+		if offset > lastOffset:
+			for (t, p) in entriesToAdd:
+				try:
+					dbCur.execute("INSERT INTO offsets VALUES (?, ?, ?, ?)", (t, p, lastOffset, offset))
+				except sqlite3.IntegrityError as e:
+					# Accounts for certain entries in the file that have the same title
+					print(f"Failed on title \"{t}\": {e}", file=sys.stderr)
+			entriesToAdd = []
+			lastOffset = offset
+		entriesToAdd.append([title, pageId])
+for (title, pageId) in entriesToAdd:
+	try:
+		dbCur.execute("INSERT INTO offsets VALUES (?, ?, ?, ?)", (title, pageId, lastOffset, -1))
+	except sqlite3.IntegrityError as e:
+		print(f"Failed on title \"{t}\": {e}", file=sys.stderr)
+
+print("Closing database")
+dbCon.commit()
+dbCon.close()