diff options
Diffstat (limited to 'python/sandcrawler')
-rw-r--r-- | python/sandcrawler/__init__.py | 2 | ||||
-rw-r--r-- | python/sandcrawler/misc.py | 84 |
2 files changed, 85 insertions, 1 deletions
diff --git a/python/sandcrawler/__init__.py b/python/sandcrawler/__init__.py index 0120287..0691b6e 100644 --- a/python/sandcrawler/__init__.py +++ b/python/sandcrawler/__init__.py @@ -1,3 +1,3 @@ from .grobid import GrobidClient -from .misc import gen_file_metadata, b32_hex +from .misc import gen_file_metadata, b32_hex, parse_cdx_line, parse_cdx_datetime diff --git a/python/sandcrawler/misc.py b/python/sandcrawler/misc.py index e13b5e7..f741f93 100644 --- a/python/sandcrawler/misc.py +++ b/python/sandcrawler/misc.py @@ -2,6 +2,7 @@ import base64 import magic import hashlib +import datetime def gen_file_metadata(blob): """ @@ -41,3 +42,86 @@ def b32_hex(s): raise ValueError("not a base-32 encoded SHA-1 hash: {}".format(s)) return base64.b16encode(base64.b32decode(s.upper())).lower().decode('utf-8') +NORMAL_MIME = ( + 'application/pdf', + 'application/postscript', + 'text/html', + 'text/xml', +) + +def normalize_mime(raw): + raw = raw.lower() + for norm in NORMAL_MIME: + if raw.startswith(norm): + return norm + + # Special cases + if raw.startswith('application/xml'): + return 'text/xml' + if raw.startswith('application/x-pdf'): + return 'application/pdf' + return None + + +def test_normalize_mime(): + assert normalize_mime("asdf") is None + assert normalize_mime("application/pdf") == "application/pdf" + assert normalize_mime("application/pdf+journal") == "application/pdf" + assert normalize_mime("Application/PDF") == "application/pdf" + assert normalize_mime("application/p") is None + assert normalize_mime("application/xml+stuff") == "text/xml" + assert normalize_mime("application/x-pdf") == "application/pdf" + assert normalize_mime("application/x-html") is None + + +def parse_cdx_line(raw_cdx, normalize=True): + + cdx = raw_cdx.split() + if len(cdx) < 11: + return None + + surt = cdx[0] + dt = cdx[1] + url = cdx[2] + mime = normalize_mime(cdx[3]) + if normalize: + mime = normalize_mime(mime) + http_status = cdx[4] + sha1b32 = cdx[5] + c_size = cdx[8] + offset = cdx[9] + warc = cdx[10] + + if not (sha1b32.isalnum() and c_size.isdigit() and offset.isdigit() + and len(sha1b32) == 32 and dt.isdigit()): + return None + + if '-' in (surt, dt, url, http_status, sha1b32, c_size, offset, warc): + return None + + if mime is None or mime == '-': + mime = "application/octet-stream" + + sha1hex = b32_hex(sha1b32) + http_status = int(http_status) + c_size = int(c_size) + offset = int(offset) + + return dict( + surt=surt, + url=url, + datetime=dt, + mimetype=mime, + http_status=http_status, + sha1b32=sha1b32, + sha1hex=sha1hex, + c_size=c_size, + offset=offset, + warc=warc, + ) + +def parse_cdx_datetime(dt_str): + try: + return datetime.strptime(dt_str, "%Y%m%d%H%M%S") + except Exception: + return None |