I have a somewhat complex use-case for the fulltext features in AQL. I have a large, hierarchical document that is returned as the result of a graph traversal. This constructs something like a social network feed. It's analogous to posts of various categories with comments as child documents that contain their own structures. The returned data looks something like this:
[
{
"data": {
"_key": "",
"_id": "someCollection/someKey",
"_rev": "",
"userID": "12345",
"otherAttributeOfFeedEvent": "",
.
.
.
},
"date": "2016-10-25",
"category": "",
"children": [
{
"category": "",
"child": "myCollection/childDocumentKey",
"date": "2016-10-26"
},
{ sameStructureAsAbove },
{ anotherChildLikeAbove },
]
},
{ etc }
]
Of course, the attributes that would be fulltext searched for each of these event types that go into a feed are different and numerous, and I need to, for a given user input, search them all simultaneously. My initial thought is that, since the _key of each document, no matter whether a parent or child in the feed, is guaranteed to be listed in this structure, I could create some sort of collection that contains all the documents as identified by their keys.
A challenge is that this fulltext search needs to retain the hierarchy. Back to the social network comments analogy, if a user searches a term that exists in a comment (i.e. a child event), the query should return the parent event with a flag on every child event that matched the term, so that the interface can display the context for the search result (else, a secondary query to get the context would be needed).
This hierarchical structure as defined above is generated by a graph traversal on a graph with a structure that looks something like this:
profile ---> event ---> childEvent
| ^
| |
\------------------/
The query that generates the data looks something like this:
let events = (
for v, e, p in 1..3 outbound @profileKey graph 'myGraph' options { "uniqueEdges": "global"}
filter e.type == "hasEvent"
filter p.edges[0].category in ["cat1", "cat2", "cat3"]
filter e.category in ["cat1", "cat2", "cat3"]
let children = (
for v1, e1, p1 in outbound v._id graph 'myGraph'
filter e1.type =="hasEvent" or e1.isChildEvent == "True"
sort (e1.date) desc
return {category: e1.category, child: v1._id, date: e1.date }
)
let date = e.date
let category = e.category
let data = v
return distinct { data: data, date: date, category: category, children: children }
)
for event in events
sort(event.date) desc
return event
Bottom line
So to sum up my question: I need to write AQL that will perform fulltext search on several attributes from every document that shows up in the described feed and return a structured result, or something that can be used in a structured result, to display a feed of the same structure as described above containing only events that match or have children that match the fulltext search results.
In my testing, I tried creating a query like this:
let events = (
FOR v, e, p in 1..3 OUTBOUND 'myCollection/myDocument' GRAPH 'myGraph' OPTIONS { "uniqueEdges": "global" }
FILTER e.type == "hasEvent"
FILTER (p.edges[0].category in ["cat1", "cat2", "cat3"] )
FILTER (e.category in ["cat1","cat2","cat3] )
LET children = (
FOR v1, e1, p1 in OUTBOUND v._id GRAPH 'myGraph'
FILTER e1.type == "hasEvent" OR e1.isChildEvent == "True"
SORT(e1.date) DESC
RETURN {category: e1.category, _id: v1._id, date: e1.date}
)
let date = e.date
let category = e.category
let data = v
RETURN DISTINCT {data: data, date: date, category: category, children: children}
)
let eventIds = (
for event in events
return event.data._id
)
let childEventIds = (
for event in events
for child in event.children
return child._id
)
let allIds = append(eventIds, childEventIds)
let allDocs = (for doc in allIds
return document(doc))
let firstAttributeMatches = (for doc in fulltext(allDocs, "firstAttribute", @queryTerm)
return doc._id)
let secondAttributeMatches = (for doc in fulltext(allDocs, "secondAttribute", @queryTerm)
return doc._id)
let nthAttributeMatches = (for doc in fulltext(allDocs, "nthAttribute", @queryTerm)
return doc._id)
let results = union_distinct(firstAttributeMatches,secondAttributeMatches,nthAttributeMatches)
return results
But this had the error: Query: invalid argument type in call to function 'FULLTEXT()' (while executing)
Presumably, even though there are fulltext indices on all of the attributes I used, because I've collected all these documents into a new collection that is not also fulltext indexed, I cannot simply call fulltext() on them. Does this mean my best bet is to just get a list of all the document collections returned by my first query, perform global fulltext searches on those collections, then inner-join the result to the result of my first query? That sounds extremely complex and time-intensive. Is there some simpler way to do what I'm after?
My next try looked more like this:
let events = (
FOR v, e, p in 1..3 OUTBOUND 'myCollection/myDocument' GRAPH 'myGraph' OPTIONS { "uniqueEdges": "global" }
FILTER e.type == "hasEvent"
FILTER (p.edges[0].category in ["cat1", "cat2", "cat3"] )
FILTER (e.category in ["cat1", "cat2", "cat3"] )
LET children = (
FOR v1, e1, p1 in OUTBOUND v._id GRAPH 'myGraph'
FILTER e1.type == "hasEvent" OR e1.isChildEvent == "True"
SORT(e1.date) DESC
RETURN {category: e1.category, _id: v1._id, date: e1.date}
)
let date = e.date
let category = e.category
let data = v
RETURN DISTINCT {data: data, date: date, category: category, children: children}
)
let eventIds = (
for event in events
return event.data._id
)
let childEventIds = (
for event in events
for child in event.children
return child._id
)
let allIds = append(eventIds, childEventIds)
let losCollections = (for id in allIds
return distinct parse_identifier(id).collection)
let searchAttrs = ["attr1","attr2","attr3","attrN"]
for col in losCollections
for attr in searchAttrs
return (for doc in fulltext(col, attr, @queryTerm) return doc._id)
But this seems to fail whenever it tries an attribute that isn't a fulltext index in the collection. Maybe there's a way in AQL to check if the attribute has a fulltext index, then only perform the query in that case?
