Add UUID support (#76)

* added to_mysql function for UUID conversion to string. * Fixed missing require * changed uuid read/write to binary and added spec tests * fixed spec test * correct fix for uuid spec test * Update spec/db_spec.cr Co-Authored-By: Brian J. Cardiff <[email protected]> * update uuid specs * update spec test for 5.6 tests * fix for uuid slice * added better read for uuid * added missing uuid logic to text_result_set * Remove code * Refactor null_bitmap handling into mysql_read * Handle nillable UUID * Use sample_value helper to test read/write UUIDs * Support UUID for binary columns only unify behavior across sql versions.The user will need to do String <-> UUID conversion manually or via mapping converters if UUID are wanted to be stored as text * Avoid dup in slice, allow StaticArray args as blobs Co-authored-by: Brian J. Cardiff <[email protected]>
crystal-lang · Oct 7, 2020 · 2deace7 · 2deace7
1 parent 435b68e
commit 2deace7
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Showing 5 changed files with 103 additions and 13 deletions.
diff --git a/spec/db_spec.cr b/spec/db_spec.cr
@@ -43,6 +43,8 @@ DB::DriverSpecs(MySql::Any).run do
   sample_value Time::Span.new(nanoseconds: 0), "Time", "TIME('00:00:00')"
   sample_value Time::Span.new(hours: 10, minutes: 25, seconds: 21), "Time", "TIME('10:25:21')"
   sample_value Time::Span.new(days: 0, hours: 0, minutes: 10, seconds: 5, nanoseconds: 0), "Time", "TIME('00:10:05.000')"
+  sample_value UUID.new("87b3042b-9b9a-41b7-8b15-a93d3f17025e"), "BLOB", "X'87b3042b9b9a41b78b15a93d3f17025e'", type_safe_value: false
+  sample_value UUID.new("87b3042b-9b9a-41b7-8b15-a93d3f17025e"), "binary(16)", %(UNHEX(REPLACE("87b3042b-9b9a-41b7-8b15-a93d3f17025e", "-",""))), type_safe_value: false
 
   DB.open db_url do |db|
     # needs to check version, microsecond support >= 5.7
@@ -231,4 +233,30 @@ DB::DriverSpecs(MySql::Any).run do
     db.query_one("SELECT EXISTS(SELECT 1 FROM data WHERE id = ?);", 1, as: Bool).should be_true
     db.query_one("SELECT EXISTS(SELECT 1 FROM data WHERE id = ?);", 2, as: Bool).should be_false
   end
+
+  it "should raise when reading UUID from text columns" do |db|
+    db.exec "create table data (id int not null primary key auto_increment, uuid_text varchar(36));"
+    db.exec %(insert into data (uuid_text) values ("87b3042b-9b9a-41b7-8b15-a93d3f17025e");)
+
+    expect_raises(DB::Error, "The column uuid_text of type MySql::Type::VarString returns a String and can't be read as UUID") do
+      db.prepared.query_one("SELECT uuid_text FROM data", as: UUID)
+    end
+
+    expect_raises(DB::Error, "The column uuid_text of type MySql::Type::VarString returns a String and can't be read as UUID") do
+      db.unprepared.query_one("SELECT uuid_text FROM data", as: UUID)
+    end
+  end
+
+  it "should raise when reading UUID from binary columns with invalid length" do |db|
+    db.exec "create table data (id int not null primary key auto_increment, uuid_blob blob);"
+    db.exec %(insert into data (uuid_blob) values (X'415A617A');)
+
+    expect_raises(ArgumentError, "Invalid bytes length 4, expected 16") do
+      db.prepared.query_one("SELECT uuid_blob FROM data", as: UUID)
+    end
+
+    expect_raises(ArgumentError, "Invalid bytes length 4, expected 16") do
+      db.unprepared.query_one("SELECT uuid_blob FROM data", as: UUID)
+    end
+  end
 end
diff --git a/src/mysql.cr b/src/mysql.cr
@@ -10,7 +10,7 @@ module MySql
     end
   end
 
-  alias Any = DB::Any | Int16 | Int8 | Time::Span
+  alias Any = DB::Any | Int16 | Int8 | Time::Span | UUID
 
   # :nodoc:
   TIME_ZONE = Time::Location::UTC

diff --git a/src/mysql/result_set.cr b/src/mysql/result_set.cr
@@ -63,31 +63,51 @@ class MySql::ResultSet < DB::ResultSet
     @columns[index].name
   end
 
-  def read
+  protected def mysql_read
     row_packet = @row_packet.not_nil!
 
     is_nil = @null_bitmap[@column_index + 2]
     col = @column_index
     @column_index += 1
     if is_nil
       nil
-    elsif false
-      # this is need to make read "return" a Bool
-      # otherwise the base `#read(T) forall T` (which is ovewriten)
-      # complains to cast `read.as(Bool)` since the return type
-      # of #read would be a union without Bool
-      false
     else
-      val = @columns[col].column_type.read(row_packet)
+      column = @columns[col]
+      yield row_packet, column
+    end
+  end
+
+  def read
+    mysql_read do |row_packet, column|
+      val = column.column_type.read(row_packet)
+
       # http://dev.mysql.com/doc/internals/en/character-set.html
-      if val.is_a?(Slice(UInt8)) && @columns[col].character_set != 63
+      if val.is_a?(Slice(UInt8)) && column.character_set != 63
         ::String.new(val)
       else
         val
       end
     end
   end
 
+  def read(t : UUID.class)
+    read(UUID?).as(UUID)
+  end
+
+  def read(t : (UUID | Nil).class)
+    mysql_read do |row_packet, column|
+      if column.flags.bits_set?(128)
+        data = row_packet.read_blob
+        # Check if binary flag is set
+        # https://dev.mysql.com/doc/dev/mysql-server/latest/group__group__cs__column__definition__flags.html#gaf74577f0e38eed5616a090965aeac323
+        UUID.new data
+      else
+        data = column.column_type.read(row_packet)
+        raise ::DB::Error.new("The column #{column.name} of type #{column.column_type} returns a #{data.class} and can't be read as UUID")
+      end
+    end
+  end
+
   def read(t : Bool.class)
     MySql::Type.from_mysql(read.as(Int::Signed))
   end

diff --git a/src/mysql/text_result_set.cr b/src/mysql/text_result_set.cr
@@ -62,7 +62,7 @@ class MySql::TextResultSet < DB::ResultSet
     @columns[index].name
   end
 
-  def read
+  protected def mysql_read
     row_packet = @row_packet.not_nil!
 
     if @first_row_packet
@@ -78,19 +78,46 @@ class MySql::TextResultSet < DB::ResultSet
     if is_nil
       nil
     else
+      column = @columns[col]
       length = row_packet.read_lenenc_int(current_byte)
+      yield row_packet, column, length
+    end
+  end
+
+  def read
+    mysql_read do |row_packet, column, length|
       val = row_packet.read_string(length)
-      val = @columns[col].column_type.parse(val)
+      val = column.column_type.parse(val)
 
       # http://dev.mysql.com/doc/internals/en/character-set.html
-      if val.is_a?(Slice(UInt8)) && @columns[col].character_set != 63
+      if val.is_a?(Slice(UInt8)) && column.character_set != 63
         ::String.new(val)
       else
         val
       end
     end
   end
 
+  def read(t : UUID.class)
+    read(UUID?).as(UUID)
+  end
+
+  def read(t : (UUID | Nil).class)
+    mysql_read do |row_packet, column, length|
+      if column.flags.bits_set?(128)
+        # Check if binary flag is set
+        # https://dev.mysql.com/doc/dev/mysql-server/latest/group__group__cs__column__definition__flags.html#gaf74577f0e38eed5616a090965aeac323
+        ary = row_packet.read_byte_array(length)
+        val = Bytes.new(ary.to_unsafe, ary.size)
+
+        UUID.new val
+      else
+        val = row_packet.read_string(length)
+        raise ::DB::Error.new("The column #{column.name} of type #{column.column_type} returns a #{val.class} and can't be read as UUID")
+      end
+    end
+  end
+
   def read(t : Bool.class)
     MySql::Type.from_mysql(read.as(Int::Signed))
   end

diff --git a/src/mysql/types.cr b/src/mysql/types.cr
@@ -1,3 +1,5 @@
+require "uuid"
+
 # :nodoc:
 abstract struct MySql::Type
   # Column types
@@ -48,6 +50,10 @@ abstract struct MySql::Type
     MySql::Type::Blob
   end
 
+  def self.type_for(t : ::StaticArray(T, N).class) forall T, N
+    MySql::Type::Blob
+  end
+
   def self.type_for(t : ::Time.class)
     MySql::Type::DateTime
   end
@@ -96,6 +102,11 @@ abstract struct MySql::Type
     v ? 1i8 : 0i8
   end
 
+  # :nodoc:
+  def self.to_mysql(v : ::UUID)
+    v.bytes
+  end
+
   # :nodoc:
   def self.from_mysql(v : Int::Signed) : Bool
     v != 0
@@ -284,6 +295,10 @@ abstract struct MySql::Type
       packet.write_blob v
     end
 
+    def self.write(packet, v : ::StaticArray(T, N)) forall T, N
+      packet.write_blob v.to_slice
+    end
+
     def self.read(packet)
       packet.read_blob
     end