def get_file_by_name(self, coll_name, name):
"""
根据文件名从gridFS获取文件
:param coll_name:
:param name:
:return:
"""
try:
fs = GridFS(self.db, coll_name)
gf = fs.find({'name': name})
if not gf:
return None
data = gf.read()
info = {
"chunk_size": gf.chunk_size,
"metadata": gf.metadata,
"length": gf.length,
"upload_data": gf.upload_date,
"name": gf.name,
"content-type": gf.content_type
}
except Exception:
raise exc.FindException(
'{}Get file by name from "{}" failed! Name: {}, error: '
'{}'.format(self.log_prefix, coll_name, name,
traceback.format_exc()))
return data, info
def get_file_by_id(self, coll_name, file_id):
"""
根据ObjectId从gridFS获取文件
:param coll_name: 集合名
:param file_id: 文件唯一ID
:return: 文件数据流和文件信息
"""
try:
fs = GridFS(self.db, coll_name)
gf = fs.get(ObjectId(file_id))
if not gf:
return None
data = gf.read()
info = {
"chunk_size": gf.chunk_size,
"metadata": gf.metadata,
"length": gf.length,
"upload_data": gf.upload_date,
"name": gf.name,
"content-type": gf.content_type
}
except Exception:
raise exc.FindException(
'{}Get file from "{}" failed! _id: {}, error: {}'.format(
self.log_prefix, coll_name, file_id,
traceback.format_exc()))
return data, info
def find_many(self,
coll_name,
offset=None,
limit=None,
sfilter=None,
aggregate=False,
sort_str=None,
projection=None):
"""
分页查询所有数据
:param coll_name:collection name
:type coll_name: str
:param offset: 偏移量，为0则表示查询全部
:type offset: int
:param limit: 每页条数
:type limit: int
:param aggregate: 是否为聚合操作
:type aggregate: bool
:param sort_str: 排序依据
:type sort_str: str
:param projection: 决定输出哪些字段
:type projection: dict
:return:
"""
callback = self.default_callback
try:
if aggregate:
ret = list(
self.run_command(coll_name, 'aggregate', callback,
sfilter))
leng = len(ret)
if offset:
ret = ret[offset::1]
if limit:
ret = ret[0:limit:1]
else:
# pymongo是在list转换的时候才会真正查询数据库，在此之前只是一个游标
ret = self.run_command(coll_name,
'find',
callback,
sfilter,
projection=projection)
if isinstance(offset, int):
ret = ret.skip(offset)
if isinstance(limit, int):
ret = ret.limit(limit)
if isinstance(sort_str, str):
ret = ret.sort([(sort_str, pymongo.DESCENDING)])
leng = self.get_count(coll_name, sfilter)
return list(ret), leng
except Exception:
raise exc.FindException(
'{}Find data from collection "{}" failed! Error: {}'.format(
self.log_prefix, coll_name, traceback.format_exc()))
def get_count(self, coll_name, sfilter):
"""
获取记录个数
:param coll_name:
:param sfilter:
:return:
"""
callback = self.default_callback
try:
count = self.run_command(coll_name,
'count',
callback,
filter=sfilter)
except Exception:
raise exc.FindException(
'{}Get data count from collection "{}" failed! Error: '
'{}'.format(self.log_prefix, coll_name,
traceback.format_exc()))
return count
def find_one(self, coll_name, sfilter, aggregate=False):
"""
查询单条数据
:param coll_name: collection name
:param sfilter: 查询条件
:param aggregate: 是否为聚合操作
:return:
"""
callback = self.default_callback
try:
if aggregate:
ret = self.run_command(coll_name, 'aggregate', callback,
sfilter)
else:
ret = self.run_command(coll_name, 'find_one', callback,
sfilter)
return ret
except Exception:
raise exc.FindException(
'{}Find data from database "{}" failed! Error: {}'.format(
self.log_prefix, coll_name, traceback.format_exc()))