refactor: simplify addJoinConditions
* remove unnecessary Either * remove implicitJoins from ReadQuery * remove unnecessary foldr in addJoinConditions * move aliasing to addRels
This commit is contained in:
steve-chavez
committed by
Steve Chavez
Steve Chavez
parent
b2b92e75cc
commit
06c9e246f4
@@ -87,7 +87,7 @@ initReadRequest rootQi rootAlias =
|
||||
rootDepth = 0
|
||||
rootSchema = qiSchema rootQi
|
||||
rootName = qiName rootQi
|
||||
initial = Node (Select [] rootQi rootAlias [] [] [] [] allRange, (rootName, Nothing, Nothing, Nothing, Nothing, rootDepth)) []
|
||||
initial = Node (Select [] rootQi rootAlias [] [] [] allRange, (rootName, Nothing, Nothing, Nothing, Nothing, rootDepth)) []
|
||||
treeEntry :: Depth -> Tree SelectItem -> ReadRequest -> ReadRequest
|
||||
treeEntry depth (Node fld@((fn, _),_,alias, hint, joinType) fldForest) (Node (q, i) rForest) =
|
||||
let nxtDepth = succ depth in
|
||||
@@ -95,7 +95,7 @@ initReadRequest rootQi rootAlias =
|
||||
[] -> Node (q {select=fld:select q}, i) rForest
|
||||
_ -> Node (q, i) $
|
||||
foldr (treeEntry nxtDepth)
|
||||
(Node (Select [] (QualifiedIdentifier rootSchema fn) Nothing [] [] [] [] allRange,
|
||||
(Node (Select [] (QualifiedIdentifier rootSchema fn) Nothing [] [] [] allRange,
|
||||
(fn, Nothing, alias, hint, joinType, nxtDepth)) [])
|
||||
fldForest:rForest
|
||||
|
||||
@@ -109,16 +109,19 @@ treeRestrictRange maxRows _ request = pure $ nodeRestrictRange maxRows <$> reque
|
||||
|
||||
augmentRequestWithJoin :: Schema -> RelationshipsMap -> ReadRequest -> Either ApiRequestError ReadRequest
|
||||
augmentRequestWithJoin schema allRels request =
|
||||
addRels schema allRels Nothing request
|
||||
>>= addJoinConditions Nothing
|
||||
addJoinConditions Nothing <$> addRels schema allRels Nothing request
|
||||
|
||||
addRels :: Schema -> RelationshipsMap -> Maybe ReadRequest -> ReadRequest -> Either ApiRequestError ReadRequest
|
||||
addRels schema allRels parentNode (Node (query@Select{from=tbl}, (nodeName, _, alias, hint, joinType, depth)) forest) =
|
||||
case parentNode of
|
||||
Just (Node (Select{from=parentNodeQi, fromAlias=aliasQi}, _) _) ->
|
||||
let newFrom r = if qiName tbl == nodeName then relForeignTable r else tbl
|
||||
newReadNode = (\r -> (query{from=newFrom r}, (nodeName, Just r, alias, hint, joinType, depth))) <$> rel
|
||||
origin = if depth == 1 -- Only on depth 1 we check if the parent(depth 0) has an alias so the sourceCTEName alias can be found as a relationship
|
||||
newReadNode = (\r ->
|
||||
if not $ relIsSelf r -- add alias if self rel TODO consolidate aliasing in another function
|
||||
then (query{from=newFrom r}, (nodeName, Just r, alias, hint, joinType, depth))
|
||||
else (query{from=newFrom r, fromAlias=Just (qiName (newFrom r) <> "_" <> show depth)}, (nodeName, Just r, alias, hint, joinType, depth))
|
||||
) <$> rel
|
||||
origin = if depth == 1 -- Only on depth 1 we check if the root(depth 0) has an alias so the sourceCTEName alias can be found as a relationship
|
||||
then fromMaybe (qiName parentNodeQi) aliasQi
|
||||
else qiName parentNodeQi
|
||||
rel = findRel schema allRels origin nodeName hint
|
||||
@@ -131,6 +134,27 @@ addRels schema allRels parentNode (Node (query@Select{from=tbl}, (nodeName, _, a
|
||||
updateForest :: Maybe ReadRequest -> Either ApiRequestError [ReadRequest]
|
||||
updateForest rq = addRels schema allRels rq `traverse` forest
|
||||
|
||||
-- applies aliasing to join conditions TODO refactor, this should go into the querybuilder module
|
||||
addJoinConditions :: Maybe Alias -> ReadRequest -> ReadRequest
|
||||
addJoinConditions _ (Node node@(Select{fromAlias=tblAlias}, (_, Nothing, _, _, _, _)) forest) = Node node (addJoinConditions tblAlias <$> forest)
|
||||
addJoinConditions previousAlias (Node (query@Select{fromAlias=tblAlias}, nodeProps@(_, Just (Relationship QualifiedIdentifier{qiSchema=tSchema, qiName=tN} QualifiedIdentifier{qiName=ftN} _ card _ _), _, _, _, _)) forest) =
|
||||
Node (query{joinConditions=joinConds}, nodeProps) (addJoinConditions tblAlias <$> forest)
|
||||
where
|
||||
joinConds =
|
||||
case card of
|
||||
M2M (Junction QualifiedIdentifier{qiName=jtn} _ _ jcols1 jcols2) ->
|
||||
(toJoinCondition Nothing Nothing ftN jtn <$> jcols2) ++ (toJoinCondition previousAlias tblAlias tN jtn <$> jcols1)
|
||||
O2M _ cols ->
|
||||
toJoinCondition previousAlias tblAlias tN ftN <$> cols
|
||||
M2O _ cols ->
|
||||
toJoinCondition previousAlias tblAlias tN ftN <$> cols
|
||||
toJoinCondition :: Maybe Alias -> Maybe Alias -> Text -> Text -> (FieldName, FieldName) -> JoinCondition
|
||||
toJoinCondition prAl newAl tb ftb (c, fc) =
|
||||
let qi1 = QualifiedIdentifier tSchema ftb
|
||||
qi2 = QualifiedIdentifier tSchema tb in
|
||||
JoinCondition (maybe qi1 (QualifiedIdentifier mempty) newAl, fc)
|
||||
(maybe qi2 (QualifiedIdentifier mempty) prAl, c)
|
||||
|
||||
-- Finds a relationship between an origin and a target in the request:
|
||||
-- /origin?select=target(*) If more than one relationship is found then the
|
||||
-- request is ambiguous and we return an error. In that case the request can
|
||||
@@ -210,46 +234,6 @@ findRel schema allRels origin target hint =
|
||||
)
|
||||
) $ fromMaybe mempty $ HM.lookup (QualifiedIdentifier schema origin, schema) allRels
|
||||
|
||||
-- previousAlias is only used for the case of self joins
|
||||
addJoinConditions :: Maybe Alias -> ReadRequest -> Either ApiRequestError ReadRequest
|
||||
addJoinConditions previousAlias (Node node@(query@Select{from=tbl,fromAlias=tblAlias}, nodeProps@(_, rel, _, _, _, depth)) forest) =
|
||||
case rel of
|
||||
Just r@Relationship{relCardinality=M2M Junction{junTable}} ->
|
||||
let rq = augmentQuery r in
|
||||
Node (rq{implicitJoins=junTable:implicitJoins rq}, nodeProps) <$> updatedForest
|
||||
Just r -> Node (augmentQuery r, nodeProps) <$> updatedForest
|
||||
Nothing -> Node node <$> updatedForest
|
||||
where
|
||||
newAlias = if depth == 0
|
||||
then tblAlias -- only use the alias on the root node(depth 0) for when the sourceCTEName alias is used for joining
|
||||
else case relIsSelf <$> rel of -- no need to apply the self reference alias on depth 0 only on the next depths
|
||||
Just True -> Just (qiName tbl <> "_" <> show depth)
|
||||
_ -> Nothing
|
||||
augmentQuery r =
|
||||
foldr
|
||||
(\jc rq@Select{joinConditions=jcs} -> rq{joinConditions=jc:jcs})
|
||||
query{fromAlias=newAlias}
|
||||
(getJoinConditions previousAlias newAlias r)
|
||||
updatedForest = addJoinConditions newAlias `traverse` forest
|
||||
|
||||
-- previousAlias and newAlias are used in the case of self joins
|
||||
getJoinConditions :: Maybe Alias -> Maybe Alias -> Relationship -> [JoinCondition]
|
||||
getJoinConditions previousAlias newAlias (Relationship QualifiedIdentifier{qiSchema=tSchema, qiName=tN} QualifiedIdentifier{qiName=ftN} _ card _ _) =
|
||||
case card of
|
||||
M2M (Junction QualifiedIdentifier{qiName=jtn} _ _ jcols1 jcols2) ->
|
||||
(toJoinCondition previousAlias newAlias tN jtn <$> jcols1) ++ (toJoinCondition Nothing Nothing ftN jtn <$> jcols2)
|
||||
O2M _ cols ->
|
||||
toJoinCondition previousAlias newAlias tN ftN <$> cols
|
||||
M2O _ cols ->
|
||||
toJoinCondition previousAlias newAlias tN ftN <$> cols
|
||||
where
|
||||
toJoinCondition :: Maybe Alias -> Maybe Alias -> Text -> Text -> (FieldName, FieldName) -> JoinCondition
|
||||
toJoinCondition prAl newAl tb ftb (c, fc) =
|
||||
let qi1 = QualifiedIdentifier tSchema tb
|
||||
qi2 = QualifiedIdentifier tSchema ftb in
|
||||
JoinCondition (maybe qi1 (QualifiedIdentifier mempty) prAl, c)
|
||||
(maybe qi2 (QualifiedIdentifier mempty) newAl, fc)
|
||||
|
||||
addFilters :: ApiRequest -> ReadRequest -> Either ApiRequestError ReadRequest
|
||||
addFilters ApiRequest{..} rReq =
|
||||
foldr addFilterToNode (Right rReq) flts
|
||||
|
||||
@@ -31,10 +31,8 @@ type SelectItem = (Field, Maybe Cast, Maybe Alias, Maybe Hint, Maybe JoinType)
|
||||
data ReadQuery = Select
|
||||
{ select :: [SelectItem]
|
||||
, from :: QualifiedIdentifier
|
||||
-- ^ A table alias is used in case of self joins
|
||||
, fromAlias :: Maybe Alias
|
||||
-- ^ Only used for Many to Many joins. Parent and Child joins use explicit joins.
|
||||
, implicitJoins :: [QualifiedIdentifier]
|
||||
-- ^ A table alias is used in case of self joins
|
||||
, where_ :: [LogicTree]
|
||||
, joinConditions :: [JoinCondition]
|
||||
, order :: [OrderTerm]
|
||||
|
||||
Reference in New Issue
Block a user