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556 | with
Ada.IO_Exceptions,
Ada.Strings.Fixed;
with
System.Storage_Elements;
with
GNAT.SHA1;
with
Black.Parsing,
Black.Text_IO;
package body Black.Response is
function Parse (Item : in String) return Access_Control.HTTP_Method_Set;
procedure Put_Line
(Stream : not null access Ada.Streams.Root_Stream_Type'Class;
Item : in Access_Control.HTTP_Method_Set);
procedure Put_Line
(Stream : not null access Ada.Streams.Root_Stream_Type'Class;
Item : in Access_Controls);
function Bad_Request (Content_Type : in String := MIME_Types.Text.Plain;
Data : in String) return Instance is
use Ada.Strings.Unbounded;
begin
return Instance'(Status => HTTP.Bad_Request,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Data),
Access_Control => <>);
end Bad_Request;
function Content (Response : in Instance) return String is
begin
-- TODO: Ought to raise a constraint error, if the content type
-- isn't text/plain.
return Ada.Strings.Unbounded.To_String (Response.Content);
end Content;
function Content_Type (Response : in Instance) return String is
begin
return Ada.Strings.Unbounded.To_String (Response.Content_Type);
end Content_Type;
function Create (Status : HTTP.Statuses) return Instance is
begin
case Status is
when HTTP.Switching_Protocols =>
return Instance'(Status => HTTP.Switching_Protocols,
Content_Type => <>,
Content => <>,
Access_Control => <>,
Websocket_Accept => <>);
when HTTP.OK =>
return Instance'(Status => HTTP.OK,
Content_Type => <>,
Content => <>,
Access_Control => <>);
when HTTP.No_Content =>
return Instance'(Status => HTTP.No_Content,
Content_Type => <>,
Content => <>,
Access_Control => <>);
when HTTP.Moved_Permanently =>
return Instance'(Status => HTTP.Moved_Permanently,
Content_Type => <>,
Content => <>,
Access_Control => <>,
Location => <>);
when HTTP.Moved_Temporarily =>
return Instance'(Status => HTTP.Moved_Temporarily,
Content_Type => <>,
Content => <>,
Access_Control => <>,
Location => <>);
when HTTP.Bad_Request =>
return Instance'(Status => HTTP.Bad_Request,
Content_Type => <>,
Content => <>,
Access_Control => <>);
when HTTP.Unauthorized =>
return Instance'(Status => HTTP.Unauthorized,
Content_Type => <>,
Content => <>,
Access_Control => <>);
when HTTP.Forbidden =>
return Instance'(Status => HTTP.Forbidden,
Content_Type => <>,
Content => <>,
Access_Control => <>);
when HTTP.Not_Found =>
return Instance'(Status => HTTP.Not_Found,
Content_Type => <>,
Content => <>,
Access_Control => <>);
when HTTP.Server_Error =>
return Instance'(Status => HTTP.Server_Error,
Content_Type => <>,
Content => <>,
Access_Control => <>);
end case;
end Create;
function Forbidden (Content_Type : in String := MIME_Types.Text.Plain;
Data : in String) return Instance is
use Ada.Strings.Unbounded;
begin
return Instance'(Status => HTTP.Forbidden,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Data),
Access_Control => <>);
end Forbidden;
function Input_HTTP
(Stream : not null access Ada.Streams.Root_Stream_Type'Class)
return Instance is
use Ada.Strings.Unbounded;
use Text_IO;
use type HTTP.Header_Key;
Status : HTTP.Statuses;
Header : Parsing.Header;
Line : Parsing.Header_Line;
Got_Content_Length : Boolean := False;
Content_Length : Natural := 0;
begin
Status := Parsing.Parse (Get_Line (Stream));
Header := Parsing.Get (Stream);
return R : Instance (Status) do
while not Parsing.End_Of_Header (Header) loop
Parsing.Read (Stream => Stream,
From => Header,
Item => Line);
-- Excessive cyclomatic complexity: Refactor!!!
if Line.Key = "Content-Type" then
R.Content_Type := Line.Value;
elsif Line.Key = "Content-Length" then
Got_Content_Length := True;
Content_Length := Line.Value;
elsif Line.Key = "Location" then
R.Location := Line.Value;
elsif Line.Key = "Sec-Websocket-Accept" then
R.Websocket_Accept :=
HTTP.Websocket_Accept_Key (String'(Line.Value));
elsif Line.Key = "Access-Control-Allow-Origin" then
R.Access_Control.Allow_Origin := Line.Value;
elsif Line.Key = "Access-Control-Allow-Credentials" then
R.Access_Control.Allow_Credentials := (Set => True,
Value => Line.Value);
elsif Line.Key = "Access-Control-Allow-Headers" then
R.Access_Control.Allow_Headers := Parse (Line.Value);
elsif Line.Key = "Access-Control-Max-Age" then
R.Access_Control.Max_Age := (Set => True,
Value => Line.Value);
end if;
end loop;
if Got_Content_Length then
declare
subtype Content is String (1 .. Content_Length);
Buffer : Content;
begin
Content'Read (Stream, Buffer);
R.Content := To_Unbounded_String (Buffer);
end;
else
declare
Buffer : Character;
begin
loop
Character'Read (Stream, Buffer);
Append (R.Content, Buffer);
end loop;
exception
when Ada.IO_Exceptions.End_Error =>
null;
end;
end if;
end return;
end Input_HTTP;
function No_Content return Instance is
begin
return Instance'(Status => HTTP.No_Content,
Content_Type => <>,
Content => <>,
Access_Control => <>);
end No_Content;
function Not_Found (Resource : in String) return Instance is
begin
return Not_Found (Data => "The requested resource, '" & Resource &
"' was not found on the server.");
end Not_Found;
function Not_Found (Content_Type : in String := MIME_Types.Text.Plain;
Data : in String) return Instance is
use Ada.Strings.Unbounded;
begin
return Instance'(Status => HTTP.Not_Found,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Data),
Access_Control => <>);
end Not_Found;
function OK (Content_Type : in String;
Data : in Ada.Streams.Stream_Element_Array)
return Instance is
use Ada.Strings.Unbounded;
pragma Assert (Ada.Streams.Stream_Element'Size = Character'Size);
Buffer : String (1 .. Data'Length);
for Buffer'Address use Data'Address;
begin
return Instance'(Status => HTTP.OK,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Buffer),
Access_Control => <>);
end OK;
function OK (Content_Type : in String := MIME_Types.Text.Plain;
Data : in String) return Instance is
use Ada.Strings.Unbounded;
begin
return Instance'(Status => HTTP.OK,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Data),
Access_Control => <>);
end OK;
procedure Output
(Stream : not null access Ada.Streams.Root_Stream_Type'Class;
Item : in Class) is
begin
Output_HTTP (Stream, Item);
end Output;
procedure Output_HTTP
(Stream : not null access Ada.Streams.Root_Stream_Type'Class;
Item : in Instance) is
use Ada.Strings.Unbounded;
use type HTTP.Statuses;
begin
if Length (Item.Content) > 0 and Length (Item.Content_Type) = 0 then
raise Constraint_Error
with "Response object is not ready to be streamed. " &
"No content-type provided for content.";
elsif Item.Status = HTTP.Moved_Permanently and then
Length (Item.Location) = 0
then
raise Constraint_Error
with "Response object is not ready to be streamed. " &
"No location provided for redirection.";
elsif Item.Status = HTTP.Moved_Temporarily and then
Length (Item.Location) = 0
then
raise Constraint_Error
with "Response object is not ready to be streamed. " &
"No location provided for redirection.";
else
declare
use Text_IO;
begin
Put_Line (Stream, HTTP.Status_Line (Item.Status));
Put (Stream, "Content-Length: ");
Put_Line (Stream, Length (Item.Content));
if Length (Item.Content) > 0 then
Put (Stream, "Content-Type: ");
Put_Line (Stream, Item.Content_Type);
end if;
case Item.Status is
when HTTP.Switching_Protocols =>
Put_Line (Stream, "Upgrade: websocket");
Put_Line (Stream, "Connection: Upgrade");
Put (Stream, "Sec-WebSocket-Accept: ");
Put_Line (Stream, String (Item.Websocket_Accept));
when HTTP.Moved_Permanently | HTTP.Moved_Temporarily =>
Put (Stream, "Location: ");
Put_Line (Stream, Item.Location);
when others =>
null;
end case;
Put_Line (Stream, Item.Access_Control);
New_Line (Stream);
Put (Stream, Item.Content);
end;
end if;
end Output_HTTP;
function Parse (Item : in String) return Access_Control.HTTP_Method_Set is
use Ada.Strings, Ada.Strings.Fixed;
From : Integer;
To : Natural := Item'First - 1;
begin
return Result : Access_Control.HTTP_Method_Set := (others => False) do
loop
From := To + 1;
exit when not (From in Item'Range);
To := Index (Item (From .. Item'Last), ",");
if To = 0 then
To := Item'Last + 1;
end if;
declare
Name : String renames Trim (Item (From .. To - 1), Both);
Method : HTTP.Methods renames HTTP.Methods'Value (Name);
begin
Result (Method) := True;
end;
end loop;
end return;
exception
when others =>
raise Protocol_Error
with "Could not parse Access-Control-Allow-Methods value.";
end Parse;
procedure Put_Line
(Stream : not null access Ada.Streams.Root_Stream_Type'Class;
Item : in Access_Control.HTTP_Method_Set) is
First : Boolean := True;
begin
for Method in Item'Range loop
if Item (Method) then
if not First then
Text_IO.Put (Target => Stream,
Item => ", ");
end if;
Text_IO.Put (Target => Stream,
Item => HTTP.Methods'Image (Method));
First := False;
end if;
end loop;
Text_IO.New_Line (Target => Stream);
end Put_Line;
procedure Put_Line
(Stream : not null access Ada.Streams.Root_Stream_Type'Class;
Item : in Access_Controls) is
use Ada.Strings.Unbounded;
use Text_IO;
No_Headers : constant Access_Control.HTTP_Method_Set :=
(others => False);
use type Access_Control.HTTP_Method_Set;
begin
if Length (Item.Allow_Origin) > 0 then
Put (Stream, "Access-Control-Allow-Origin: ");
Put_Line (Stream, Item.Allow_Origin);
end if;
if Item.Allow_Credentials.Set then
Put (Stream, "Access-Control-Allow-Credentials: ");
Put_Line (Stream, Item.Allow_Credentials.Value);
end if;
if Item.Allow_Headers /= No_Headers then
Put (Stream, "Access-Control-Allow-Headers: ");
Put_Line (Stream, Item.Allow_Headers);
end if;
if Item.Max_Age.Set then
Put (Stream, "Access-Control-Max-Age: ");
Put_Line (Stream, Item.Max_Age.Value);
end if;
end Put_Line;
function Redirect (Target : in String;
Permanent : in Boolean)
return Instance is
use Ada.Strings.Unbounded;
begin
if Permanent then
return Instance'(Status => HTTP.Moved_Permanently,
Content_Type => <>,
Content => <>,
Access_Control => <>,
Location => To_Unbounded_String (Target));
else
return Instance'(Status => HTTP.Moved_Temporarily,
Content_Type => <>,
Content => <>,
Access_Control => <>,
Location => To_Unbounded_String (Target));
end if;
end Redirect;
function Server_Error (Content_Type : in String := MIME_Types.Text.Plain;
Data : in String) return Instance is
use Ada.Strings.Unbounded;
begin
return Instance'(Status => HTTP.Server_Error,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Data),
Access_Control => <>);
end Server_Error;
function Status (Response : in Instance) return HTTP.Statuses is
begin
return Response.Status;
end Status;
function Switch_To_Websocket (Key : in String) return Instance is
function Accept_Key return HTTP.Websocket_Accept_Key;
function To_Storage_Elements
(Hex : in String)
return System.Storage_Elements.Storage_Array;
function Base64 (Octets : in System.Storage_Elements.Storage_Array)
return String;
function Accept_Key return HTTP.Websocket_Accept_Key is
use GNAT.SHA1;
Hash : Context := Initial_Context;
begin
Update (Hash, Key);
Update (Hash, "258EAFA5-E914-47DA-95CA-C5AB0DC85B11");
return HTTP.Websocket_Accept_Key
(Base64 (To_Storage_Elements (Digest (Hash))));
end Accept_Key;
function Base64 (Octets : in System.Storage_Elements.Storage_Array)
return String is
use System.Storage_Elements;
subtype Sextet is Storage_Element range 0 .. 2 ** 6 - 1;
Alphabet : constant array (Sextet) of Character :=
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" &
"abcdefghijklmnopqrstuvwxyz" &
"0123456789+/";
O_Pos : Storage_Offset := Octets'First;
Result : String (1 .. (Octets'Length + 2) / 3 * 4) := (others => '_');
R_Pos : Positive := Result'First;
begin
while O_Pos in Octets'Range loop
declare
A, B, C, D : Sextet;
begin
First_Byte :
declare
First : Storage_Element renames Octets (O_Pos);
begin
A := (First and 2#1111_1100#) / 2 ** 2;
B := (First and 2#0000_0011#) * 2 ** 4;
if O_Pos = Octets'Last then
Result (R_Pos .. R_Pos + 3) :=
Alphabet (A) & Alphabet (B) & "==";
return Result;
end if;
end First_Byte;
Second_Byte :
declare
Second : Storage_Element renames Octets (O_Pos + 1);
begin
B := B or (Second and 2#1111_0000#) / 2 ** 4;
C := (Second and 2#0000_1111#) * 2 ** 2;
if O_Pos + 1 = Octets'Last then
Result (R_Pos .. R_Pos + 3) :=
Alphabet (A) & Alphabet (B) & Alphabet (C) & "=";
return Result;
end if;
end Second_Byte;
Third_Byte :
declare
Third : Storage_Element renames Octets (O_Pos + 2);
begin
C := C or (Third and 2#1100_0000#) / 2 ** 6;
D := (Third and 2#0011_1111#);
end Third_Byte;
Result (R_Pos .. R_Pos + 3) :=
Alphabet (A) & Alphabet (B) & Alphabet (C) & Alphabet (D);
O_Pos := O_Pos + 3;
R_Pos := R_Pos + 4;
end;
end loop;
return Result;
end Base64;
function To_Storage_Elements
(Hex : in String)
return System.Storage_Elements.Storage_Array is
use System.Storage_Elements;
begin
pragma Assert (Hex'Length mod 2 = 0, "We only process octets.");
return Octets : Storage_Array (0 .. Hex'Length / 2 - 1) do
for Index in Octets'Range loop
declare
Hex_Offset : constant Positive :=
Hex'First + Positive'Base (2 * Index);
begin
Octets (Index) :=
Storage_Element'Value
("16#" & Hex (Hex_Offset .. Hex_Offset + 1) & "#");
end;
end loop;
end return;
end To_Storage_Elements;
use Text_IO;
begin
return Instance'(Status => HTTP.Switching_Protocols,
Content_Type => <>,
Content => <>,
Access_Control => <>,
Websocket_Accept => Accept_Key);
end Switch_To_Websocket;
function Unauthorized (Content_Type : in String := MIME_Types.Text.Plain;
Data : in String) return Instance is
use Ada.Strings.Unbounded;
begin
return Instance'(Status => HTTP.Unauthorized,
Content_Type => To_Unbounded_String (Content_Type),
Content => To_Unbounded_String (Data),
Access_Control => <>);
end Unauthorized;
package body Access_Control is
procedure Allow_Credentials (Item : in out Class) is
begin
Item.Access_Control.Allow_Credentials := (Set => True,
Value => True);
end Allow_Credentials;
procedure Allow_Headers (Item : in out Class;
Headers : in HTTP_Method_Set) is
begin
Item.Access_Control.Allow_Headers := Headers;
end Allow_Headers;
procedure Allow_Origin (Item : in out Class;
Pattern : in String) is
use Ada.Strings.Unbounded;
begin
Item.Access_Control.Allow_Origin := To_Unbounded_String (Pattern);
end Allow_Origin;
procedure Max_Age (Item : in out Class;
Age : in Duration) is
begin
Item.Access_Control.Max_Age := (Set => True,
Value => Age);
end Max_Age;
end Access_Control;
end Black.Response;
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