Add Sqlite blob type (#70)

Author: elcritch

ormin/ormin_sqlite.nim

@@ -11,6 +11,7 @@ type
   DbConn* = PSqlite3  ## encapsulates a database connection
 
   varcharType* = string
+  blobType* = seq[byte]
   intType* = int
   floatType* = float
   boolType* = bool
@@ -36,7 +37,15 @@ template startBindings*(s: PStmt; n: int) =
 template bindParam*(db: DbConn; s: PStmt; idx: int; x, t: untyped) =
   #when not (x is t):
   #  {.error: "type mismatch for query argument at position " & $idx.}
-  when t is int or t is int64 or t is bool:
+  when t is blobType:
+    let xs = x
+    let blobPtr = if xs.len == 0:
+        cast[pointer](nil)
+      else:
+        cast[pointer](unsafeAddr(xs[0]))
+    if bind_blob(s, idx.cint, blobPtr, xs.len.cint, SQLITE_STATIC) != SQLITE_OK:
+      dbError(db)
+  elif t is int or t is int64 or t is bool:
     if bind_int64(s, idx.cint, x.int64) != SQLITE_OK: dbError(db)
   elif t is string:
     if bind_text(s, idx.cint, cstring(x), x.len.cint, SQLITE_STATIC) != SQLITE_OK:
@@ -75,7 +84,7 @@ template bindFromJson*(db: DbConn; s: PStmt; idx: int; x: JsonNode;
                        t: typedesc[string]) =
   doAssert x.kind == JString
   let xs = x.str
-  if bind_blob(s, idx.cint, cstring(xs), xs.len.cint, SQLITE_STATIC) != SQLITE_OK:
+  if bind_text(s, idx.cint, cstring(xs), xs.len.cint, SQLITE_STATIC) != SQLITE_OK:
     dbError(db)
 
 template bindFromJson*(db: DbConn; s: PStmt; idx: int; x: JsonNode;
@@ -127,12 +136,27 @@ proc fillString(dest: var string; src: cstring; srcLen: int) =
     else: setLen(dest, srcLen)
   copyMem(unsafeAddr(dest[0]), src, srcLen)
 
+proc fillBytes(dest: var seq[byte]; src: pointer; srcLen: int) =
+  if srcLen == 0: return
+  when defined(nimNoNilSeqs):
+    setLen(dest, srcLen)
+  else:
+    if dest.isNil: dest = newSeq[byte](srcLen)
+    else: setLen(dest, srcLen)
+  copyMem(unsafeAddr(dest[0]), src, srcLen)
+
 template bindResult*(db: DbConn; s: PStmt; idx: int; dest: var string;
                      t: typedesc; name: string) =
   let srcLen = column_bytes(s, idx.cint)
   let src = column_text(s, idx.cint)
   fillString(dest, src, srcLen)
 
+template bindResult*(db: DbConn; s: PStmt; idx: int; dest: var blobType;
+                     t: typedesc; name: string) =
+  let srcLen = column_bytes(s, idx.cint)
+  let src = column_blob(s, idx.cint)
+  fillBytes(dest, src, srcLen)
+
 template bindResult*(db: DbConn; s: PStmt; idx: int; dest: float64;
                      t: typedesc; name: string) =
   dest = column_double(s, idx.cint)
@@ -184,6 +208,17 @@ template bindToJson*(db: DbConn; s: PStmt; idx: int; obj: JsonNode;
                      t: typedesc[int|int64]; name: string) =
   obj[name] = newJInt(column_int64(s, idx.cint))
 
+template bindToJson*(db: DbConn; s: PStmt; idx: int; obj: JsonNode;
+                     t: typedesc[blobType]; name: string) =
+  let srcLen = column_bytes(s, idx.cint)
+  let src = column_blob(s, idx.cint)
+  var data: blobType
+  fillBytes(data, src, srcLen)
+  let arr = newJArray()
+  for b in data:
+    arr.add newJInt(int(b))
+  obj[name] = arr
+
 template bindToJson*(db: DbConn; s: PStmt; idx: int; obj: JsonNode;
                      t: typedesc[float64]; name: string) =
   obj[name] = newJFloat(column_double(s, idx.cint))

tests/model_sqlite.sql

@@ -22,4 +22,9 @@ create table if not exists tb_timestamp(
 
 create table if not exists tb_json(
   typjson json not null
-);
+);
+
+create table if not exists tb_blob(
+  id integer primary key,
+  typblob blob not null
+);

tests/tsqlite.nim

@@ -24,6 +24,18 @@ let
               "dt2": dt2.format(jsonTimeFormat)}
 let insertSql =  sql"insert into tb_timestamp(dt1, dt2) values (?, ?)"
 
+proc blobFromBytes(bytes: openArray[int]): seq[byte] =
+  result = newSeq[byte](bytes.len)
+  for i, b in bytes:
+    doAssert b >= 0 and b <= 255
+    result[i] = byte(b)
+
+let blobFixtures = [
+  blobFromBytes(@[0, 1, 2, 3, 4, 5, 6, 7]),
+  blobFromBytes(@[255, 128, 64, 32, 16, 8, 4, 2, 1]),
+  blobFromBytes(@[ord('O'), ord('R'), ord('M'), ord('I'), ord('N'), 0, 1, 2])
+]
+
 suite "timestamp_insert":
   setup:
     db.dropTable(sqlFile, "tb_timestamp")
@@ -94,3 +106,36 @@ suite "timestamp":
       where dt1 == %dtjson["dt1"]
       produce json
     check res == %*[dtjson]
+
+suite "blob_insert":
+  setup:
+    db.dropTable(sqlFile, "tb_blob")
+    db.createTable(sqlFile, "tb_blob")
+
+  test "insert parameters":
+    for blob in blobFixtures:
+      query:
+        insert tb_blob(typblob = ?blob)
+    check db.getValue(sql"select count(*) from tb_blob") == $blobFixtures.len
+
+suite "blob":
+  db.dropTable(sqlFile, "tb_blob")
+  db.createTable(sqlFile, "tb_blob")
+
+  for blob in blobFixtures:
+    query:
+      insert tb_blob(typblob = ?blob)
+  doAssert db.getValue(sql"select count(*) from tb_blob") == $blobFixtures.len
+
+  test "query":
+    let res = query:
+      select tb_blob(id, typblob)
+    check res.mapIt(it.typblob) == blobFixtures
+
+  test "where":
+    let target = blobFixtures[1]
+    let res = query:
+      select tb_blob(id, typblob)
+      where typblob == ?target
+    check res.len == 1
+    check res[0].typblob == target