mirror of
https://github.com/overleaf/overleaf.git
synced 2024-10-31 21:21:03 -04:00
373 lines
12 KiB
CoffeeScript
373 lines
12 KiB
CoffeeScript
async = require "async"
|
|
_ = require "underscore"
|
|
{db, ObjectId} = require "./mongojs"
|
|
BSON=db.bson.BSON
|
|
|
|
module.exports = PackManager =
|
|
# The following functions implement methods like a mongo find, but
|
|
# expands any documents containing a 'pack' field into multiple
|
|
# values
|
|
#
|
|
# e.g. a single update looks like
|
|
#
|
|
# {
|
|
# "doc_id" : 549dae9e0a2a615c0c7f0c98,
|
|
# "project_id" : 549dae9c0a2a615c0c7f0c8c,
|
|
# "op" : [ {"p" : 6981, "d" : "?" } ],
|
|
# "meta" : { "user_id" : 52933..., "start_ts" : 1422310693931, "end_ts" : 1422310693931 },
|
|
# "v" : 17082
|
|
# }
|
|
#
|
|
# and a pack looks like this
|
|
#
|
|
# {
|
|
# "doc_id" : 549dae9e0a2a615c0c7f0c98,
|
|
# "project_id" : 549dae9c0a2a615c0c7f0c8c,
|
|
# "pack" : [ U1, U2, U3, ...., UN],
|
|
# "meta" : { "user_id" : 52933..., "start_ts" : 1422310693931, "end_ts" : 1422310693931 },
|
|
# "v" : 17082
|
|
# }
|
|
#
|
|
# where U1, U2, U3, .... are single updates stripped of their
|
|
# doc_id and project_id fields (which are the same for all the
|
|
# updates in the pack).
|
|
#
|
|
# The pack itself has v and meta fields, this makes it possible to
|
|
# treat packs and single updates in the same way.
|
|
#
|
|
# The v field of the pack itself is from the first entry U1
|
|
# The meta.end_ts field of the pack itself is from the last entry UN.
|
|
|
|
findDocResults: (collection, query, limit, callback) ->
|
|
# query - the mongo query selector, includes both the doc_id/project_id and
|
|
# the range on v
|
|
# limit - the mongo limit, we need to apply it after unpacking any
|
|
# packs
|
|
|
|
sort = {}
|
|
sort['v'] = -1;
|
|
cursor = collection
|
|
.find( query )
|
|
.sort( sort )
|
|
# if we have packs, we will trim the results more later after expanding them
|
|
if limit?
|
|
cursor.limit(limit)
|
|
|
|
# take the part of the query which selects the range over the parameter
|
|
rangeQuery = query['v']
|
|
|
|
# helper function to check if an item from a pack is inside the
|
|
# desired range
|
|
filterFn = (item) ->
|
|
return false if rangeQuery?['$gte']? && item['v'] < rangeQuery['$gte']
|
|
return false if rangeQuery?['$lte']? && item['v'] > rangeQuery['$lte']
|
|
return false if rangeQuery?['$lt']? && item['v'] >= rangeQuery['$lt']
|
|
return false if rangeQuery?['$gt']? && item['v'] <= rangeQuery['$gt']
|
|
return true
|
|
|
|
versionOrder = (a, b) ->
|
|
b.v - a.v
|
|
|
|
# create a query which can be used to select the entries BEFORE
|
|
# the range because we sometimes need to find extra ones (when the
|
|
# boundary falls in the middle of a pack)
|
|
extraQuery = _.clone(query)
|
|
# The pack uses its first entry for its metadata and v, so the
|
|
# only queries where we might not get all the packs are those for
|
|
# $gt and $gte (i.e. we need to find packs which start before our
|
|
# range but end in it)
|
|
if rangeQuery?['$gte']?
|
|
extraQuery['v'] = {'$lt' : rangeQuery['$gte']}
|
|
else if rangeQuery?['$gt']
|
|
extraQuery['v'] = {'$lte' : rangeQuery['$gt']}
|
|
else
|
|
delete extraQuery['v']
|
|
|
|
needMore = false # keep track of whether we need to load more data
|
|
updates = [] # used to accumulate the set of results
|
|
cursor.toArray (err, result) ->
|
|
unpackedSet = PackManager._unpackResults(result)
|
|
updates = PackManager._filterAndLimit(updates, unpackedSet, filterFn, limit)
|
|
# check if we need to retrieve more data, because there is a
|
|
# pack that crosses into our range
|
|
last = if unpackedSet.length then unpackedSet[unpackedSet.length-1] else null
|
|
if limit? && updates.length == limit
|
|
needMore = false
|
|
else if extraQuery['v']? && last? && filterFn(last)
|
|
needMore = true
|
|
else if extraQuery['v']? && updates.length == 0
|
|
needMore = true
|
|
if needMore
|
|
# we do need an extra result set
|
|
extra = collection
|
|
.find(extraQuery)
|
|
.sort(sort)
|
|
.limit(1)
|
|
extra.toArray (err, result2) ->
|
|
if err?
|
|
return callback err, updates.sort versionOrder
|
|
else
|
|
extraSet = PackManager._unpackResults(result2)
|
|
updates = PackManager._filterAndLimit(updates, extraSet, filterFn, limit)
|
|
callback err, updates.sort versionOrder
|
|
return
|
|
if err?
|
|
callback err, result
|
|
else
|
|
callback err, updates.sort versionOrder
|
|
|
|
findProjectResults: (collection, query, limit, callback) ->
|
|
# query - the mongo query selector, includes both the doc_id/project_id and
|
|
# the range on meta.end_ts
|
|
# limit - the mongo limit, we need to apply it after unpacking any
|
|
# packs
|
|
|
|
sort = {}
|
|
sort['meta.end_ts'] = -1;
|
|
|
|
projection = {"op":false, "pack.op": false}
|
|
cursor = collection
|
|
.find( query, projection ) # no need to return the op only need version info
|
|
.sort( sort )
|
|
# if we have packs, we will trim the results more later after expanding them
|
|
if limit?
|
|
cursor.limit(limit)
|
|
|
|
# take the part of the query which selects the range over the parameter
|
|
before = query['meta.end_ts']?['$lt'] # may be null
|
|
|
|
updates = [] # used to accumulate the set of results
|
|
|
|
cursor.toArray (err, result) ->
|
|
if err?
|
|
return callback err, result
|
|
if result.length == 0 && not before? # no results and no time range specified
|
|
return callback err, result
|
|
|
|
unpackedSet = PackManager._unpackResults(result)
|
|
if limit?
|
|
unpackedSet = unpackedSet.slice(0, limit)
|
|
# find the end time of the last result, we will take all the
|
|
# results up to this, and then all the changes at that time
|
|
# (without imposing a limit) and any overlapping packs
|
|
cutoff = if unpackedSet.length then unpackedSet[unpackedSet.length-1].meta.end_ts else null
|
|
|
|
filterFn = (item) ->
|
|
ts = item?.meta?.end_ts
|
|
return false if before? && ts >= before
|
|
return false if cutoff? && ts < cutoff
|
|
return true
|
|
|
|
timeOrder = (a, b) ->
|
|
(b.meta.end_ts - a.meta.end_ts) || documentOrder(a, b)
|
|
|
|
documentOrder = (a, b) ->
|
|
x = a.doc_id.valueOf()
|
|
y = b.doc_id.valueOf()
|
|
if x > y then 1 else if x < y then -1 else 0
|
|
|
|
updates = PackManager._filterAndLimit(updates, unpackedSet, filterFn, limit)
|
|
|
|
# get all elements on the lower bound (cutoff)
|
|
tailQuery = _.clone(query)
|
|
tailQuery['meta.end_ts'] = cutoff
|
|
tail = collection
|
|
.find(tailQuery, projection)
|
|
.sort(sort)
|
|
|
|
# now find any packs that overlap with the time window
|
|
overlapQuery = _.clone(query)
|
|
if before? && cutoff?
|
|
overlapQuery['meta.end_ts'] = {"$gte": before}
|
|
overlapQuery['pack.0.meta.end_ts'] = {"$lte": before }
|
|
else if before? && not cutoff?
|
|
overlapQuery['meta.end_ts'] = {"$gte": before}
|
|
overlapQuery['pack.0.meta.end_ts'] = {"$lte": before }
|
|
else if not before? && cutoff?
|
|
overlapQuery['meta.end_ts'] = {"$gte": cutoff}
|
|
overlapQuery['pack.0.meta.end_ts'] = {"$gte": 0 }
|
|
else if not before? && not cutoff?
|
|
overlapQuery['meta.end_ts'] = {"$gte": 0 }
|
|
overlapQuery['pack.0.meta.end_ts'] = {"$gte": 0 }
|
|
overlap = collection
|
|
.find(overlapQuery, projection)
|
|
.sort(sort)
|
|
|
|
# we don't specify a limit here, as there could be any number of overlaps
|
|
# NB. need to catch items in original query and followup query for duplicates
|
|
|
|
applyAndUpdate = (result) ->
|
|
extraSet = PackManager._unpackResults(result)
|
|
# note: final argument is null, no limit applied because we
|
|
# need all the updates at the final time to avoid breaking
|
|
# the changeset into parts
|
|
updates = PackManager._filterAndLimit(updates, extraSet, filterFn, null)
|
|
tail.toArray (err, result2) ->
|
|
if err?
|
|
return callback err, updates.sort timeOrder
|
|
else
|
|
applyAndUpdate result2
|
|
overlap.toArray (err, result3) ->
|
|
if err?
|
|
return callback err, updates.sort timeOrder
|
|
else
|
|
applyAndUpdate result3
|
|
callback err, updates.sort timeOrder
|
|
|
|
_unpackResults: (updates) ->
|
|
# iterate over the updates, if there's a pack, expand it into ops and
|
|
# insert it into the array at that point
|
|
result = []
|
|
updates.forEach (item) ->
|
|
if item.pack?
|
|
all = PackManager._explodePackToOps item
|
|
result = result.concat all
|
|
else
|
|
result.push item
|
|
return result
|
|
|
|
_explodePackToOps: (packObj) ->
|
|
# convert a pack into an array of ops
|
|
doc_id = packObj.doc_id
|
|
project_id = packObj.project_id
|
|
result = packObj.pack.map (item) ->
|
|
item.doc_id = doc_id
|
|
item.project_id = project_id
|
|
item
|
|
return result.reverse()
|
|
|
|
_filterAndLimit: (results, extra, filterFn, limit) ->
|
|
# update results with extra docs, after filtering and limiting
|
|
filtered = extra.filter(filterFn)
|
|
newResults = results.concat filtered
|
|
# remove duplicates
|
|
seen = {}
|
|
newResults = newResults.filter (item) ->
|
|
key = item.doc_id + ' ' + item.v
|
|
if seen[key]
|
|
return false
|
|
else
|
|
seen[key] = true
|
|
return true
|
|
newResults.slice(0, limit) if limit?
|
|
return newResults
|
|
|
|
MAX_SIZE: 1024*1024 # make these configurable parameters
|
|
MAX_COUNT: 1024
|
|
MIN_COUNT: 100
|
|
KEEP_OPS: 100
|
|
|
|
convertDocsToPacks: (docs, callback) ->
|
|
packs = []
|
|
top = null
|
|
# keep the last KEEP_OPS as individual ops
|
|
docs = docs.slice(0,-PackManager.KEEP_OPS)
|
|
|
|
docs.forEach (d,i) ->
|
|
# skip existing packs
|
|
if d.pack?
|
|
top = null
|
|
return
|
|
# skip temporary ops (we could pack these into temporary packs in future)
|
|
if d.expiresAt?
|
|
top = null
|
|
return
|
|
sz = BSON.calculateObjectSize(d)
|
|
if top? && top.pack.length < PackManager.MAX_COUNT && top.sz + sz < PackManager.MAX_SIZE
|
|
top.pack = top.pack.concat {v: d.v, meta: d.meta, op: d.op, _id: d._id}
|
|
top.sz += sz
|
|
top.v_end = d.v
|
|
top.meta.end_ts = d.meta.end_ts
|
|
return
|
|
else if sz < PackManager.MAX_SIZE
|
|
# create a new pack
|
|
top = _.clone(d)
|
|
top.pack = [ {v: d.v, meta: d.meta, op: d.op, _id: d._id} ]
|
|
top.meta = { start_ts: d.meta.start_ts, end_ts: d.meta.end_ts }
|
|
top.sz = sz
|
|
delete top.op
|
|
delete top._id
|
|
packs.push top
|
|
else
|
|
# keep the op
|
|
# util.log "keeping large op unchanged (#{sz} bytes)"
|
|
|
|
# only store packs with a sufficient number of ops, discard others
|
|
packs = packs.filter (packObj) ->
|
|
packObj.pack.length > PackManager.MIN_COUNT
|
|
callback(null, packs)
|
|
|
|
checkHistory: (docs, callback) ->
|
|
errors = []
|
|
prev = null
|
|
error = (args...) ->
|
|
errors.push args
|
|
docs.forEach (d,i) ->
|
|
if d.pack?
|
|
n = d.pack.length
|
|
last = d.pack[n-1]
|
|
error('bad pack v_end', d) if d.v_end != last.v
|
|
error('bad pack start_ts', d) if d.meta.start_ts != d.pack[0].meta.start_ts
|
|
error('bad pack end_ts', d) if d.meta.end_ts != last.meta.end_ts
|
|
d.pack.forEach (p, i) ->
|
|
prev = v
|
|
v = p.v
|
|
error('bad version', v, 'in', p) if v <= prev
|
|
#error('expired op', p, 'in pack') if p.expiresAt?
|
|
else
|
|
prev = v
|
|
v = d.v
|
|
error('bad version', v, 'in', d) if v <= prev
|
|
if errors.length
|
|
callback(errors)
|
|
else
|
|
callback()
|
|
|
|
insertPack: (packObj, callback) ->
|
|
bulk = db.docHistory.initializeOrderedBulkOp()
|
|
expect_nInserted = 1
|
|
expect_nRemoved = packObj.pack.length
|
|
bulk.insert packObj
|
|
packObj.pack.forEach (op) ->
|
|
bulk.find({_id:op._id}).removeOne()
|
|
bulk.execute (err, result) ->
|
|
if err?
|
|
callback(err, result)
|
|
else if result.nInserted != expect_nInserted or result.nRemoved != expect_nRemoved
|
|
callback(new Error(
|
|
msg: 'unexpected result'
|
|
expected: {expect_nInserted, expect_nRemoved}
|
|
), result)
|
|
else
|
|
callback(err, result)
|
|
|
|
deleteExpiredPackOps: (docs, callback) ->
|
|
now = Date.now()
|
|
toRemove = []
|
|
toUpdate = []
|
|
docs.forEach (d,i) ->
|
|
if d.pack?
|
|
newPack = d.pack.filter (op) ->
|
|
if op.expiresAt? then op.expiresAt > now else true
|
|
if newPack.length == 0
|
|
toRemove.push d
|
|
else if newPack.length < d.pack.length
|
|
# adjust the pack properties
|
|
d.pack = newPack
|
|
first = d.pack[0]
|
|
last = d.pack[d.pack.length - 1]
|
|
d.v_end = last.v
|
|
d.meta.start_ts = first.meta.start_ts
|
|
d.meta.end_ts = last.meta.end_ts
|
|
toUpdate.push d
|
|
if toRemove.length or toUpdate.length
|
|
bulk = db.docHistory.initializeOrderedBulkOp()
|
|
toRemove.forEach (pack) ->
|
|
console.log "would remove", pack
|
|
#bulk.find({_id:pack._id}).removeOne()
|
|
toUpdate.forEach (pack) ->
|
|
console.log "would update", pack
|
|
#bulk.find({_id:pack._id}).updateOne(pack);
|
|
bulk.execute callback
|
|
else
|
|
callback()
|