{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE QuasiQuotes #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeSynonymInstances #-}
{-# LANGUAGE NamedFieldPuns #-}
module PostgREST.DbStructure (
getDbStructure
, accessibleTables
, accessibleProcs
, schemaDescription
, getPgVersion
) where
import qualified Hasql.Decoders as HD
import qualified Hasql.Encoders as HE
import qualified Hasql.Query as H
import Control.Applicative
import qualified Data.HashMap.Strict as M
import qualified Data.List as L
import Data.Set as S (fromList)
import Data.Text (split, strip,
breakOn, dropAround,
splitOn)
import qualified Data.Text as T
import qualified Hasql.Session as H
import PostgREST.Types
import Text.InterpolatedString.Perl6 (q)
import GHC.Exts (groupWith)
import Protolude
import Unsafe (unsafeHead)
getDbStructure :: Schema -> PgVersion -> H.Session DbStructure
getDbStructure schema pgVer = do
tabs <- H.query () allTables
cols <- H.query schema $ allColumns tabs
syns <- H.query schema $ allSynonyms cols
childRels <- H.query () $ allChildRelations tabs cols
keys <- H.query () $ allPrimaryKeys tabs
procs <- H.query schema allProcs
let rels = addManyToManyRelations . addParentRelations $ addViewRelations syns childRels
cols' = addForeignKeys rels cols
keys' = addViewPrimaryKeys syns keys
return DbStructure {
dbTables = tabs
, dbColumns = cols'
, dbRelations = rels
, dbPrimaryKeys = keys'
, dbProcs = procs
, pgVersion = pgVer
}
decodeTables :: HD.Result [Table]
decodeTables =
HD.rowsList tblRow
where
tblRow = Table <$> HD.value HD.text
<*> HD.value HD.text
<*> HD.nullableValue HD.text
<*> HD.value HD.bool
decodeColumns :: [Table] -> HD.Result [Column]
decodeColumns tables =
mapMaybe (columnFromRow tables) <$> HD.rowsList colRow
where
colRow =
(,,,,,,,,,,,)
<$> HD.value HD.text <*> HD.value HD.text
<*> HD.value HD.text <*> HD.nullableValue HD.text
<*> HD.value HD.int4 <*> HD.value HD.bool
<*> HD.value HD.text <*> HD.value HD.bool
<*> HD.nullableValue HD.int4
<*> HD.nullableValue HD.int4
<*> HD.nullableValue HD.text
<*> HD.nullableValue HD.text
decodeRelations :: [Table] -> [Column] -> HD.Result [Relation]
decodeRelations tables cols =
mapMaybe (relationFromRow tables cols) <$> HD.rowsList relRow
where
relRow = (,,,,,)
<$> HD.value HD.text
<*> HD.value HD.text
<*> HD.value (HD.array (HD.arrayDimension replicateM (HD.arrayValue HD.text)))
<*> HD.value HD.text
<*> HD.value HD.text
<*> HD.value (HD.array (HD.arrayDimension replicateM (HD.arrayValue HD.text)))
decodePks :: [Table] -> HD.Result [PrimaryKey]
decodePks tables =
mapMaybe (pkFromRow tables) <$> HD.rowsList pkRow
where
pkRow = (,,) <$> HD.value HD.text <*> HD.value HD.text <*> HD.value HD.text
decodeSynonyms :: [Column] -> HD.Result [Synonym]
decodeSynonyms cols =
mapMaybe (synonymFromRow cols) <$> HD.rowsList synRow
where
synRow = (,,,,,)
<$> HD.value HD.text <*> HD.value HD.text
<*> HD.value HD.text <*> HD.value HD.text
<*> HD.value HD.text <*> HD.value HD.text
decodeProcs :: HD.Result (M.HashMap Text [ProcDescription])
decodeProcs =
map sort . M.fromListWith (++) . map ((\(x,y) -> (x, [y])) . addName) <$> HD.rowsList tblRow
where
tblRow = ProcDescription
<$> HD.value HD.text
<*> HD.nullableValue HD.text
<*> (parseArgs <$> HD.value HD.text)
<*> (parseRetType
<$> HD.value HD.text
<*> HD.value HD.text
<*> HD.value HD.bool
<*> HD.value HD.char)
<*> (parseVolatility <$> HD.value HD.char)
addName :: ProcDescription -> (Text, ProcDescription)
addName pd = (pdName pd, pd)
parseArgs :: Text -> [PgArg]
parseArgs = mapMaybe parseArg . filter (not . isPrefixOf "OUT" . toS) . map strip . split (==',')
parseArg :: Text -> Maybe PgArg
parseArg a =
let arg = lastDef "" $ splitOn "INOUT " a
(body, def) = breakOn " DEFAULT " arg
(name, typ) = breakOn " " body in
if T.null typ
then Nothing
else Just $
PgArg (dropAround (== '"') name) (strip typ) (T.null def)
parseRetType :: Text -> Text -> Bool -> Char -> RetType
parseRetType schema name isSetOf typ
| isSetOf = SetOf pgType
| otherwise = Single pgType
where
qi = QualifiedIdentifier schema name
pgType = case typ of
'c' -> Composite qi
'p' -> if name == "record"
then Composite qi
else Scalar qi
_ -> Scalar qi
parseVolatility :: Char -> ProcVolatility
parseVolatility v | v == 'i' = Immutable
| v == 's' = Stable
| otherwise = Volatile
allProcs :: H.Query Schema (M.HashMap Text [ProcDescription])
allProcs = H.statement (toS procsSqlQuery) (HE.value HE.text) decodeProcs True
accessibleProcs :: H.Query Schema (M.HashMap Text [ProcDescription])
accessibleProcs = H.statement (toS sql) (HE.value HE.text) decodeProcs True
where
sql = procsSqlQuery <> " AND has_function_privilege(p.oid, 'execute')"
procsSqlQuery :: SqlQuery
procsSqlQuery = [q|
SELECT p.proname as "proc_name",
d.description as "proc_description",
pg_get_function_arguments(p.oid) as "args",
tn.nspname as "rettype_schema",
coalesce(comp.relname, t.typname) as "rettype_name",
p.proretset as "rettype_is_setof",
t.typtype as "rettype_typ",
p.provolatile
FROM pg_proc p
JOIN pg_namespace pn ON pn.oid = p.pronamespace
JOIN pg_type t ON t.oid = p.prorettype
JOIN pg_namespace tn ON tn.oid = t.typnamespace
LEFT JOIN pg_class comp ON comp.oid = t.typrelid
LEFT JOIN pg_catalog.pg_description as d on d.objoid = p.oid
WHERE pn.nspname = $1
|]
schemaDescription :: H.Query Schema (Maybe Text)
schemaDescription =
H.statement sql (HE.value HE.text) (join <$> HD.maybeRow (HD.nullableValue HD.text)) True
where
sql = [q|
select
description
from
pg_catalog.pg_namespace n
left join pg_catalog.pg_description d on d.objoid = n.oid
where
n.nspname = $1 |]
accessibleTables :: H.Query Schema [Table]
accessibleTables =
H.statement sql (HE.value HE.text) decodeTables True
where
sql = [q|
select
n.nspname as table_schema,
relname as table_name,
d.description as table_description,
c.relkind = 'r' or (c.relkind IN ('v', 'f')) and (pg_relation_is_updatable(c.oid::regclass, false) & 8) = 8
or (exists (
select 1
from pg_trigger
where pg_trigger.tgrelid = c.oid and (pg_trigger.tgtype::integer & 69) = 69)
) as insertable
from
pg_class c
join pg_namespace n on n.oid = c.relnamespace
left join pg_catalog.pg_description as d on d.objoid = c.oid and d.objsubid = 0
where
c.relkind in ('v', 'r', 'm', 'f')
and n.nspname = $1
and (
pg_has_role(c.relowner, 'USAGE'::text)
or has_table_privilege(c.oid, 'SELECT, INSERT, UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER'::text)
or has_any_column_privilege(c.oid, 'SELECT, INSERT, UPDATE, REFERENCES'::text)
)
order by relname |]
addForeignKeys :: [Relation] -> [Column] -> [Column]
addForeignKeys rels = map addFk
where
addFk col = col { colFK = fk col }
fk col = join $ relToFk col <$> find (lookupFn col) rels
lookupFn :: Column -> Relation -> Bool
lookupFn c Relation{relColumns=cs, relType=rty} = c `elem` cs && rty==Child
relToFk col Relation{relColumns=cols, relFColumns=colsF} = do
pos <- L.elemIndex col cols
colF <- atMay colsF pos
return $ ForeignKey colF
{-
Adds Views Child Relations based on Synonyms found, the logic is as follows:
Having a Relation{relTable=t1, relColumns=[c1], relFTable=t2, relFColumns=[c2], relType=Child} represented by:
t1.c1------t2.c2
When only having a t1_view.c1 synonym, we need to add a View to Table Relation
t1.c1----t2.c2 t1.c1----------t2.c2
-> --------/
/
t1_view.c1 t1_view.c1
When only having a t2_view.c2 synonym, we need to add a Table to View Relation
t1.c1----t2.c2 t1.c1----------t2.c2
-> \--------
\
t2_view.c2 t2_view.c1
When having t1_view.c1 and a t2_view.c2 synonyms, we need to add a View to View Relation in addition to the prior
t1.c1----t2.c2 t1.c1----------t2.c2
-> \--------/
/ \
t1_view.c1 t2_view.c2 t1_view.c1-------t2_view.c1
The logic for composite pks is similar just need to make sure all the Relation columns have synonyms.
-}
addViewRelations :: [Synonym] -> [Relation] -> [Relation]
addViewRelations allSyns = concatMap (\rel ->
rel : case rel of
Relation{relType=Child, relTable, relColumns, relFTable, relFColumns} ->
let colSynsGroupedByView :: [Column] -> [[Synonym]]
colSynsGroupedByView relCols = L.groupBy (\(_, viewCol1) (_, viewCol2) -> colTable viewCol1 == colTable viewCol2) $
filter (\(c, _) -> c `elem` relCols) allSyns
colsSyns = colSynsGroupedByView relColumns
fColsSyns = colSynsGroupedByView relFColumns
getView :: [Synonym] -> Table
getView = colTable . snd . unsafeHead
syns `allSynsOf` cols = S.fromList (fst <$> syns) == S.fromList cols in
-- View Table Relations
[Relation (getView syns) (snd <$> syns) relFTable relFColumns Child Nothing Nothing Nothing
| syns <- colsSyns, syns `allSynsOf` relColumns] ++
-- Table View Relations
[Relation relTable relColumns (getView fSyns) (snd <$> fSyns) Child Nothing Nothing Nothing
| fSyns <- fColsSyns, fSyns `allSynsOf` relFColumns] ++
-- View View Relations
[Relation (getView syns) (snd <$> syns) (getView fSyns) (snd <$> fSyns) Child Nothing Nothing Nothing
| syns <- colsSyns, fSyns <- fColsSyns, syns `allSynsOf` relColumns, fSyns `allSynsOf` relFColumns]
_ -> [])
addParentRelations :: [Relation] -> [Relation]
addParentRelations = concatMap (\rel@(Relation t c ft fc _ _ _ _) -> [rel, Relation ft fc t c Parent Nothing Nothing Nothing])
addManyToManyRelations :: [Relation] -> [Relation]
addManyToManyRelations rels = rels ++ addMirrorRelation (mapMaybe link2Relation links)
where
links = join $ map (combinations 2) $ filter (not . null) $ groupWith groupFn $ filter ( (==Child). relType) rels
groupFn :: Relation -> Text
groupFn Relation{relTable=Table{tableSchema=s, tableName=t}} = s <> "_" <> t
-- Reference : https://wiki.haskell.org/99_questions/Solutions/26
combinations :: Int -> [a] -> [[a]]
combinations 0 _ = [ [] ]
combinations n xs = [ y:ys | y:xs' <- tails xs
, ys <- combinations (n-1) xs']
addMirrorRelation = concatMap (\rel@(Relation t c ft fc _ lt lc1 lc2) -> [rel, Relation ft fc t c Many lt lc2 lc1])
link2Relation [
Relation{relTable=lt, relColumns=lc1, relFTable=t, relFColumns=c},
Relation{ relColumns=lc2, relFTable=ft, relFColumns=fc}
]
| lc1 /= lc2 && length lc1 == 1 && length lc2 == 1 = Just $ Relation t c ft fc Many (Just lt) (Just lc1) (Just lc2)
| otherwise = Nothing
link2Relation _ = Nothing
addViewPrimaryKeys :: [Synonym] -> [PrimaryKey] -> [PrimaryKey]
addViewPrimaryKeys syns = concatMap (\pk ->
let viewPks = (\(_, viewCol) -> PrimaryKey{pkTable=colTable viewCol, pkName=colName viewCol}) <$>
filter (\(col, _) -> colTable col == pkTable pk && colName col == pkName pk) syns in
pk : viewPks)
allTables :: H.Query () [Table]
allTables =
H.statement sql HE.unit decodeTables True
where
sql = [q|
SELECT
n.nspname AS table_schema,
c.relname AS table_name,
NULL AS table_description,
c.relkind = 'r' OR (c.relkind IN ('v','f'))
AND (pg_relation_is_updatable(c.oid::regclass, FALSE) & 8) = 8
OR (EXISTS
( SELECT 1
FROM pg_trigger
WHERE pg_trigger.tgrelid = c.oid
AND (pg_trigger.tgtype::integer & 69) = 69) ) AS insertable
FROM pg_class c
JOIN pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('v','r','m','f')
AND n.nspname NOT IN ('pg_catalog', 'information_schema')
GROUP BY table_schema, table_name, insertable
ORDER BY table_schema, table_name |]
allColumns :: [Table] -> H.Query Schema [Column]
allColumns tabs =
H.statement sql (HE.value HE.text) (decodeColumns tabs) True
where
sql = [q|
SELECT DISTINCT
info.table_schema AS schema,
info.table_name AS table_name,
info.column_name AS name,
info.description AS description,
info.ordinal_position AS position,
info.is_nullable::boolean AS nullable,
info.data_type AS col_type,
info.is_updatable::boolean AS updatable,
info.character_maximum_length AS max_len,
info.numeric_precision AS precision,
info.column_default AS default_value,
array_to_string(enum_info.vals, ',') AS enum
FROM (
/*
-- CTE based on pg_catalog to get only Primary and Foreign key columns outside api schema
*/
WITH key_columns AS (
SELECT
r.oid AS r_oid,
c.oid AS c_oid,
n.nspname,
c.relname,
r.conname,
r.contype,
unnest(r.conkey) AS conkey
FROM
pg_catalog.pg_constraint r,
pg_catalog.pg_class c,
pg_catalog.pg_namespace n
WHERE
r.contype IN ('f', 'p')
AND c.relkind IN ('r', 'v', 'f', 'm')
AND r.conrelid = c.oid
AND c.relnamespace = n.oid
AND n.nspname NOT IN ('pg_catalog', 'information_schema', $1)
),
/*
-- CTE based on information_schema.columns
-- changed:
-- remove the owner filter
-- limit columns to the ones in the api schema or PK/FK columns
*/
columns AS (
SELECT current_database()::information_schema.sql_identifier AS table_catalog,
nc.nspname::information_schema.sql_identifier AS table_schema,
c.relname::information_schema.sql_identifier AS table_name,
a.attname::information_schema.sql_identifier AS column_name,
d.description::information_schema.sql_identifier AS description,
a.attnum::information_schema.cardinal_number AS ordinal_position,
pg_get_expr(ad.adbin, ad.adrelid)::information_schema.character_data AS column_default,
CASE
WHEN a.attnotnull OR t.typtype = 'd'::"char" AND t.typnotnull THEN 'NO'::text
ELSE 'YES'::text
END::information_schema.yes_or_no AS is_nullable,
CASE
WHEN t.typtype = 'd'::"char" THEN
CASE
WHEN bt.typelem <> 0::oid AND bt.typlen = (-1) THEN 'ARRAY'::text
WHEN nbt.nspname = 'pg_catalog'::name THEN format_type(t.typbasetype, NULL::integer)
ELSE format_type(a.atttypid, a.atttypmod)
END
ELSE
CASE
WHEN t.typelem <> 0::oid AND t.typlen = (-1) THEN 'ARRAY'::text
WHEN nt.nspname = 'pg_catalog'::name THEN format_type(a.atttypid, NULL::integer)
ELSE format_type(a.atttypid, a.atttypmod)
END
END::information_schema.character_data AS data_type,
information_schema._pg_char_max_length(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.cardinal_number AS character_maximum_length,
information_schema._pg_char_octet_length(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.cardinal_number AS character_octet_length,
information_schema._pg_numeric_precision(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.cardinal_number AS numeric_precision,
information_schema._pg_numeric_precision_radix(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.cardinal_number AS numeric_precision_radix,
information_schema._pg_numeric_scale(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.cardinal_number AS numeric_scale,
information_schema._pg_datetime_precision(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.cardinal_number AS datetime_precision,
information_schema._pg_interval_type(information_schema._pg_truetypid(a.*, t.*), information_schema._pg_truetypmod(a.*, t.*))::information_schema.character_data AS interval_type,
NULL::integer::information_schema.cardinal_number AS interval_precision,
NULL::character varying::information_schema.sql_identifier AS character_set_catalog,
NULL::character varying::information_schema.sql_identifier AS character_set_schema,
NULL::character varying::information_schema.sql_identifier AS character_set_name,
CASE
WHEN nco.nspname IS NOT NULL THEN current_database()
ELSE NULL::name
END::information_schema.sql_identifier AS collation_catalog,
nco.nspname::information_schema.sql_identifier AS collation_schema,
co.collname::information_schema.sql_identifier AS collation_name,
CASE
WHEN t.typtype = 'd'::"char" THEN current_database()
ELSE NULL::name
END::information_schema.sql_identifier AS domain_catalog,
CASE
WHEN t.typtype = 'd'::"char" THEN nt.nspname
ELSE NULL::name
END::information_schema.sql_identifier AS domain_schema,
CASE
WHEN t.typtype = 'd'::"char" THEN t.typname
ELSE NULL::name
END::information_schema.sql_identifier AS domain_name,
current_database()::information_schema.sql_identifier AS udt_catalog,
COALESCE(nbt.nspname, nt.nspname)::information_schema.sql_identifier AS udt_schema,
COALESCE(bt.typname, t.typname)::information_schema.sql_identifier AS udt_name,
NULL::character varying::information_schema.sql_identifier AS scope_catalog,
NULL::character varying::information_schema.sql_identifier AS scope_schema,
NULL::character varying::information_schema.sql_identifier AS scope_name,
NULL::integer::information_schema.cardinal_number AS maximum_cardinality,
a.attnum::information_schema.sql_identifier AS dtd_identifier,
'NO'::character varying::information_schema.yes_or_no AS is_self_referencing,
'NO'::character varying::information_schema.yes_or_no AS is_identity,
NULL::character varying::information_schema.character_data AS identity_generation,
NULL::character varying::information_schema.character_data AS identity_start,
NULL::character varying::information_schema.character_data AS identity_increment,
NULL::character varying::information_schema.character_data AS identity_maximum,
NULL::character varying::information_schema.character_data AS identity_minimum,
NULL::character varying::information_schema.yes_or_no AS identity_cycle,
'NEVER'::character varying::information_schema.character_data AS is_generated,
NULL::character varying::information_schema.character_data AS generation_expression,
CASE
WHEN c.relkind = 'r'::"char" OR (c.relkind = ANY (ARRAY['v'::"char", 'f'::"char"])) AND pg_column_is_updatable(c.oid::regclass, a.attnum, false) THEN 'YES'::text
ELSE 'NO'::text
END::information_schema.yes_or_no AS is_updatable
FROM pg_attribute a
LEFT JOIN key_columns kc ON kc.conkey = a.attnum AND kc.c_oid = a.attrelid
LEFT JOIN pg_catalog.pg_description AS d ON d.objoid = a.attrelid and d.objsubid = a.attnum
LEFT JOIN pg_attrdef ad ON a.attrelid = ad.adrelid AND a.attnum = ad.adnum
JOIN (pg_class c
JOIN pg_namespace nc ON c.relnamespace = nc.oid) ON a.attrelid = c.oid
JOIN (pg_type t
JOIN pg_namespace nt ON t.typnamespace = nt.oid) ON a.atttypid = t.oid
LEFT JOIN (pg_type bt
JOIN pg_namespace nbt ON bt.typnamespace = nbt.oid) ON t.typtype = 'd'::"char" AND t.typbasetype = bt.oid
LEFT JOIN (pg_collation co
JOIN pg_namespace nco ON co.collnamespace = nco.oid) ON a.attcollation = co.oid AND (nco.nspname <> 'pg_catalog'::name OR co.collname <> 'default'::name)
WHERE
NOT pg_is_other_temp_schema(nc.oid)
AND a.attnum > 0
AND NOT a.attisdropped
AND (c.relkind = ANY (ARRAY['r'::"char", 'v'::"char", 'f'::"char", 'm'::"char"]))
AND (nc.nspname = $1 OR kc.r_oid IS NOT NULL) /*--filter only columns that are FK/PK or in the api schema */
/*--AND (pg_has_role(c.relowner, 'USAGE'::text) OR has_column_privilege(c.oid, a.attnum, 'SELECT, INSERT, UPDATE, REFERENCES'::text))*/
)
SELECT
table_schema,
table_name,
column_name,
description,
ordinal_position,
is_nullable,
data_type,
is_updatable,
character_maximum_length,
numeric_precision,
column_default,
udt_name
/*-- FROM information_schema.columns*/
FROM columns
WHERE table_schema NOT IN ('pg_catalog', 'information_schema')
) AS info
LEFT OUTER JOIN (
SELECT
n.nspname AS s,
t.typname AS n,
array_agg(e.enumlabel ORDER BY e.enumsortorder) AS vals
FROM pg_type t
JOIN pg_enum e ON t.oid = e.enumtypid
JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace
GROUP BY s,n
) AS enum_info ON (info.udt_name = enum_info.n)
ORDER BY schema, position |]
columnFromRow :: [Table] ->
(Text, Text, Text,
Maybe Text, Int32, Bool,
Text, Bool, Maybe Int32,
Maybe Int32, Maybe Text, Maybe Text)
-> Maybe Column
columnFromRow tabs (s, t, n, desc, pos, nul, typ, u, l, p, d, e) = buildColumn <$> table
where
buildColumn tbl = Column tbl n desc pos nul typ u l p d (parseEnum e) Nothing
table = find (\tbl -> tableSchema tbl == s && tableName tbl == t) tabs
parseEnum :: Maybe Text -> [Text]
parseEnum str = fromMaybe [] $ split (==',') <$> str
allChildRelations :: [Table] -> [Column] -> H.Query () [Relation]
allChildRelations tabs cols =
H.statement sql HE.unit (decodeRelations tabs cols) True
where
sql = [q|
SELECT ns1.nspname AS table_schema,
tab.relname AS table_name,
column_info.cols AS columns,
ns2.nspname AS foreign_table_schema,
other.relname AS foreign_table_name,
column_info.refs AS foreign_columns
FROM pg_constraint,
LATERAL (SELECT array_agg(cols.attname) AS cols,
array_agg(cols.attnum) AS nums,
array_agg(refs.attname) AS refs
FROM ( SELECT unnest(conkey) AS col, unnest(confkey) AS ref) k,
LATERAL (SELECT * FROM pg_attribute
WHERE attrelid = conrelid AND attnum = col)
AS cols,
LATERAL (SELECT * FROM pg_attribute
WHERE attrelid = confrelid AND attnum = ref)
AS refs)
AS column_info,
LATERAL (SELECT * FROM pg_namespace WHERE pg_namespace.oid = connamespace) AS ns1,
LATERAL (SELECT * FROM pg_class WHERE pg_class.oid = conrelid) AS tab,
LATERAL (SELECT * FROM pg_class WHERE pg_class.oid = confrelid) AS other,
LATERAL (SELECT * FROM pg_namespace WHERE pg_namespace.oid = other.relnamespace) AS ns2
WHERE confrelid != 0
ORDER BY (conrelid, column_info.nums) |]
relationFromRow :: [Table] -> [Column] -> (Text, Text, [Text], Text, Text, [Text]) -> Maybe Relation
relationFromRow allTabs allCols (rs, rt, rcs, frs, frt, frcs) =
Relation <$> table <*> cols <*> tableF <*> colsF <*> pure Child <*> pure Nothing <*> pure Nothing <*> pure Nothing
where
findTable s t = find (\tbl -> tableSchema tbl == s && tableName tbl == t) allTabs
findCol s t c = find (\col -> tableSchema (colTable col) == s && tableName (colTable col) == t && colName col == c) allCols
table = findTable rs rt
tableF = findTable frs frt
cols = mapM (findCol rs rt) rcs
colsF = mapM (findCol frs frt) frcs
allPrimaryKeys :: [Table] -> H.Query () [PrimaryKey]
allPrimaryKeys tabs =
H.statement sql HE.unit (decodePks tabs) True
where
sql = [q|
/*
-- CTE to replace information_schema.table_constraints to remove owner limit
*/
WITH tc AS (
SELECT current_database()::information_schema.sql_identifier AS constraint_catalog,
nc.nspname::information_schema.sql_identifier AS constraint_schema,
c.conname::information_schema.sql_identifier AS constraint_name,
current_database()::information_schema.sql_identifier AS table_catalog,
nr.nspname::information_schema.sql_identifier AS table_schema,
r.relname::information_schema.sql_identifier AS table_name,
CASE c.contype
WHEN 'c'::"char" THEN 'CHECK'::text
WHEN 'f'::"char" THEN 'FOREIGN KEY'::text
WHEN 'p'::"char" THEN 'PRIMARY KEY'::text
WHEN 'u'::"char" THEN 'UNIQUE'::text
ELSE NULL::text
END::information_schema.character_data AS constraint_type,
CASE
WHEN c.condeferrable THEN 'YES'::text
ELSE 'NO'::text
END::information_schema.yes_or_no AS is_deferrable,
CASE
WHEN c.condeferred THEN 'YES'::text
ELSE 'NO'::text
END::information_schema.yes_or_no AS initially_deferred
FROM pg_namespace nc,
pg_namespace nr,
pg_constraint c,
pg_class r
WHERE nc.oid = c.connamespace AND nr.oid = r.relnamespace AND c.conrelid = r.oid AND (c.contype <> ALL (ARRAY['t'::"char", 'x'::"char"])) AND r.relkind = 'r'::"char" AND NOT pg_is_other_temp_schema(nr.oid)
/*--AND (pg_has_role(r.relowner, 'USAGE'::text) OR has_table_privilege(r.oid, 'INSERT, UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER'::text) OR has_any_column_privilege(r.oid, 'INSERT, UPDATE, REFERENCES'::text))*/
UNION ALL
SELECT current_database()::information_schema.sql_identifier AS constraint_catalog,
nr.nspname::information_schema.sql_identifier AS constraint_schema,
(((((nr.oid::text || '_'::text) || r.oid::text) || '_'::text) || a.attnum::text) || '_not_null'::text)::information_schema.sql_identifier AS constraint_name,
current_database()::information_schema.sql_identifier AS table_catalog,
nr.nspname::information_schema.sql_identifier AS table_schema,
r.relname::information_schema.sql_identifier AS table_name,
'CHECK'::character varying::information_schema.character_data AS constraint_type,
'NO'::character varying::information_schema.yes_or_no AS is_deferrable,
'NO'::character varying::information_schema.yes_or_no AS initially_deferred
FROM pg_namespace nr,
pg_class r,
pg_attribute a
WHERE nr.oid = r.relnamespace AND r.oid = a.attrelid AND a.attnotnull AND a.attnum > 0 AND NOT a.attisdropped AND r.relkind = 'r'::"char" AND NOT pg_is_other_temp_schema(nr.oid)
/*--AND (pg_has_role(r.relowner, 'USAGE'::text) OR has_table_privilege(r.oid, 'INSERT, UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER'::text) OR has_any_column_privilege(r.oid, 'INSERT, UPDATE, REFERENCES'::text))*/
),
/*
-- CTE to replace information_schema.key_column_usage to remove owner limit
*/
kc AS (
SELECT current_database()::information_schema.sql_identifier AS constraint_catalog,
ss.nc_nspname::information_schema.sql_identifier AS constraint_schema,
ss.conname::information_schema.sql_identifier AS constraint_name,
current_database()::information_schema.sql_identifier AS table_catalog,
ss.nr_nspname::information_schema.sql_identifier AS table_schema,
ss.relname::information_schema.sql_identifier AS table_name,
a.attname::information_schema.sql_identifier AS column_name,
(ss.x).n::information_schema.cardinal_number AS ordinal_position,
CASE
WHEN ss.contype = 'f'::"char" THEN information_schema._pg_index_position(ss.conindid, ss.confkey[(ss.x).n])
ELSE NULL::integer
END::information_schema.cardinal_number AS position_in_unique_constraint
FROM pg_attribute a,
( SELECT r.oid AS roid,
r.relname,
r.relowner,
nc.nspname AS nc_nspname,
nr.nspname AS nr_nspname,
c.oid AS coid,
c.conname,
c.contype,
c.conindid,
c.confkey,
c.confrelid,
information_schema._pg_expandarray(c.conkey) AS x
FROM pg_namespace nr,
pg_class r,
pg_namespace nc,
pg_constraint c
WHERE nr.oid = r.relnamespace AND r.oid = c.conrelid AND nc.oid = c.connamespace AND (c.contype = ANY (ARRAY['p'::"char", 'u'::"char", 'f'::"char"])) AND r.relkind = 'r'::"char" AND NOT pg_is_other_temp_schema(nr.oid)) ss
WHERE ss.roid = a.attrelid AND a.attnum = (ss.x).x AND NOT a.attisdropped
/*--AND (pg_has_role(ss.relowner, 'USAGE'::text) OR has_column_privilege(ss.roid, a.attnum, 'SELECT, INSERT, UPDATE, REFERENCES'::text))*/
)
SELECT
kc.table_schema,
kc.table_name,
kc.column_name
FROM
/*
--information_schema.table_constraints tc,
--information_schema.key_column_usage kc
*/
tc, kc
WHERE
tc.constraint_type = 'PRIMARY KEY' AND
kc.table_name = tc.table_name AND
kc.table_schema = tc.table_schema AND
kc.constraint_name = tc.constraint_name AND
kc.table_schema NOT IN ('pg_catalog', 'information_schema') |]
pkFromRow :: [Table] -> (Schema, Text, Text) -> Maybe PrimaryKey
pkFromRow tabs (s, t, n) = PrimaryKey <$> table <*> pure n
where table = find (\tbl -> tableSchema tbl == s && tableName tbl == t) tabs
allSynonyms :: [Column] -> H.Query Schema [Synonym]
allSynonyms cols =
H.statement sql (HE.value HE.text) (decodeSynonyms cols) True
-- query explanation at https://gist.github.com/steve-chavez/7ee0e6590cddafb532e5f00c46275569
where sql = [q|
with
views as (
select
n.nspname as view_schema,
c.relname as view_name,
r.ev_action as view_definition
from pg_class c
join pg_namespace n on n.oid = c.relnamespace
join pg_rewrite r on r.ev_class = c.oid
where (c.relkind = 'v'::char) and n.nspname = $1
),
removed_subselects as(
select
view_schema, view_name,
regexp_replace(view_definition, ':subselect {.*?:constraintDeps <>} :location', '', 'g') as x
from views
),
target_lists as(
select
view_schema, view_name,
regexp_split_to_array(x, 'targetList') as x
from removed_subselects
),
last_target_list_wo_tail as(
select
view_schema, view_name,
(regexp_split_to_array(x[array_upper(x, 1)], ':onConflict'))[1] as x
from target_lists
),
target_entries as(
select
view_schema, view_name,
unnest(regexp_split_to_array(x, 'TARGETENTRY')) as entry
from last_target_list_wo_tail
),
results as(
select
view_schema, view_name,
substring(entry from ':resname (.*?) :') as view_colum_name,
substring(entry from ':resorigtbl (.*?) :') as resorigtbl,
substring(entry from ':resorigcol (.*?) :') as resorigcol
from target_entries
)
select
sch.nspname as table_schema,
tbl.relname as table_name,
col.attname as table_column_name,
res.view_schema,
res.view_name,
res.view_colum_name
from results res
join pg_class tbl on tbl.oid::text = res.resorigtbl
join pg_attribute col on col.attrelid = tbl.oid and col.attnum::text = res.resorigcol
join pg_namespace sch on sch.oid = tbl.relnamespace
where resorigtbl <> '0'
order by view_schema, view_name, view_colum_name;
|]
synonymFromRow :: [Column] -> (Text,Text,Text,Text,Text,Text) -> Maybe Synonym
synonymFromRow allCols (s1,t1,c1,s2,t2,c2) = (,) <$> col1 <*> col2
where
col1 = findCol s1 t1 c1
col2 = findCol s2 t2 c2
findCol s t c = find (\col -> (tableSchema . colTable) col == s && (tableName . colTable) col == t && colName col == c) allCols
getPgVersion :: H.Session PgVersion
getPgVersion = H.query () $ H.statement sql HE.unit versionRow False
where
sql = "SELECT current_setting('server_version_num')::integer, current_setting('server_version')"
versionRow = HD.singleRow $ PgVersion <$> HD.value HD.int4 <*> HD.value HD.text