trunk/iblocaldb/IBXUpgradeConfFile.pas

(*
 *  IBX For Lazarus (Firebird Express)
 *
 *  The contents of this file are subject to the Initial Developer's
 *  Public License Version 1.0 (the "License"); you may not use this
 *  file except in compliance with the License. You may obtain a copy
 *  of the License here:
 *
 *    http://www.firebirdsql.org/index.php?op=doc&id=idpl
 *
 *  Software distributed under the License is distributed on an "AS
 *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 *  implied. See the License for the specific language governing rights
 *  and limitations under the License.
 *
 *  The Initial Developer of the Original Code is Tony Whyman.
 *
 *  The Original Code is (C) 2014 Tony Whyman, MWA Software
 *  (http://www.mwasoftware.co.uk).
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): ______________________________________.
 *
*)
unit IBXUpgradeConfFile;

{$mode objfpc}{$H+}

{
       TUpgradeConfFile encapsulated a text file in “ini” file format with
       the following sections:

       [status]

       This should have a single named value “current” giving the current database
       schema number as in integer e.g.

       current = 2

       This should normally be set to the same value as the RequiredVersionNo property
       and acts as a check to ensure that both are in sync.

       [Version.nnn]

       Where nnn is an integer with leaving zeroes. For example, “Version.002” is
       the section read to upgrade the database schema from version 1 to version 2.
       This section can contain the following named values:

       Name         Type        Use

       Upgrade      String      Name and optional path to SQL script used to perform
                                the upgrade. May either be absolute path or relative
                                to the upgrade configuration file. Either forwards or
                                back slashes may be used as the path delimiter.

       Msg          string      Text message displayed in progress dialog while script is
                                active.  Defaults to “Upgrading Database Schema to Version nnn”.

       BackupDatabase yes/no    If present and set to “yes” then a database backup in
                                gbak format is made before the upgrade is performed. The backup file is
                                located in the same directory as the database file and is given the same
                                name as the database file with the extension replaced with “.nnn.gbak”.
                                Where “nnn” is the current schema version number (i.e. prior to running
                                the upgrade script).

       <Parameter Name> string  Name and optional path to binary data file. May either be
                                absolute path or relative to the upgrade configuration file.
                                Either forwards or back slashes may be used as the path delimiter.


       For example:

       [Version.002]
       Msg = Upgrading to Version 2
       BackupDatabase = yes
       Upgrade = patches/02-patch.sql
       mugshot = images/man.png.gz

       Note that in the above, “mugshot” is intended to be used to resolve an Update,
       Insert or Delete query parameter in the 02-patch.sql file. E.g.

       Update EMPLOYEE Set Photo =:MUGSHOT Where Emp_no = 2;

       This is only applicable to BLOB columns and the above is interpreted as update
       the EMPLOYEE table where the Emp_no is “2” and set the value of the Photo column
       to the binary data contained in the file “images/man.png.gz”.
}

interface

uses
  Classes, SysUtils, IniFiles;

type
  TUpgradeInfo = record
    UpdateSQLFile,
    UserMessage: string;
    BackupDB: boolean;
  end;

{ TUpgradeConfFile }

  TUpgradeConfFile = class
  private
    FConfFileName: string;
    FCurrentVersion: string;
    FUpgradeInfo: TIniFile;
    function GetUpgradeAvailableToVersion: integer;
  public
    constructor Create(aFileName: string);
    destructor Destroy; override;
    class function IsAbsolutePath(aPath: string): boolean;
    function CheckUpgradeAvailable(RequiredVersionNo: integer): boolean;
    function GetUpgradeInfo(VersionNo: integer; var UpgradeInfo: TUpgradeInfo): boolean;
    function GetSourceFile(aName: string; var FileName: string): boolean;
    property UpgradeAvailableToVersion: integer read GetUpgradeAvailableToVersion;
  end;

  EUpgradeConfFileError = class(Exception);


implementation

const
  sSectionheader      = 'Version.%.3d';

resourcestring
  sInvalidConfFile = 'Database Upgrade Required, but the Upgrade File (%s) is missing or not specified';
  sUpgradeRequired = 'Database Upgrade Required, but the Upgrade File is out of Date. '+
                              'Required Version = %d, Upgrade available for version %d';
  sNoInfo      = 'Upgrading Database Schema to Version %d';

{ TUpgradeConfFile }

function TUpgradeConfFile.GetUpgradeAvailableToVersion: integer;
begin
  Result := StrToInt(FUpgradeInfo.ReadString('Status','Current','0'))
end;

constructor TUpgradeConfFile.Create(aFileName: string);
begin
  inherited Create;
  FConfFileName := aFileName;
  if (FConfFileName = '') or not FileExists(FConfFileName) then
     raise EUpgradeConfFileError.CreateFmt(sInvalidConfFile,[FConfFileName]);
  FUpgradeInfo := TIniFile.Create(FConfFileName);
end;

destructor TUpgradeConfFile.Destroy;
begin
  if assigned(FUpgradeInfo) then FUpgradeInfo.Free;
  inherited Destroy;
end;

class function TUpgradeConfFile.IsAbsolutePath(aPath: string): boolean;
begin
  Result := false;
  {$IFDEF WINDOWS}
    Result := (ExtractFileDrive(aPath) <> '') or
      ((Length(aPath) > 0) and (aPath[1] = DirectorySeparator));
  {$ENDIF}
  {$IFDEF UNIX}
    Result := (Length(aPath) > 0) and (aPath[1] = DirectorySeparator);
  {$ENDIF}
end;

function TUpgradeConfFile.CheckUpgradeAvailable(RequiredVersionNo: integer
  ): boolean;
var CurVersion: integer;
begin
  CurVersion := GetUpgradeAvailableToVersion;
  if CurVersion < RequiredVersionNo then
    raise EUpgradeConfFileError.CreateFmt(sUpgradeRequired, [RequiredVersionNo,CurVersion]);
end;

function TUpgradeConfFile.GetUpgradeInfo(VersionNo: integer;
  var UpgradeInfo: TUpgradeInfo): boolean;
begin
   Result := false;
   FCurrentVersion := Format(sSectionheader,[VersionNo]);
   UpgradeInfo.UserMessage := FUpgradeInfo.ReadString(FCurrentVersion,'Msg',
                                Format(sNoInfo,[VersionNo]));
   UpgradeInfo.UpdateSQLFile := FUpgradeInfo.ReadString(FCurrentVersion,'Upgrade','');
   Result := UpgradeInfo.UpdateSQLFile <> '';
   if Result then
   begin
     DoDirSeparators(UpgradeInfo.UpdateSQLFile); {Resolve Platform dependencies}
     if not IsAbsolutePath(UpgradeInfo.UpdateSQLFile) then
       UpgradeInfo.UpdateSQLFile := ExtractFilePath(FConfFileName) + UpgradeInfo.UpdateSQLFile;
     UpgradeInfo.BackupDB := CompareText(FUpgradeInfo.ReadString(FCurrentVersion,'BackupDatabase','no'),'yes') = 0;
     Result := FileExists(UpgradeInfo.UpdateSQLFile);
   end;
end;

function TUpgradeConfFile.GetSourceFile(aName: string; var FileName: string
  ): boolean;
begin
  FileName := FUpgradeInfo.ReadString(FCurrentVersion,aName,'');
  DoDirSeparators(FileName);
  if not IsAbsolutePath(FileName) then
    FileName := ExtractFilePath(FConfFileName) + FileName;
  Result := FileExists(FileName);
end;

end.

Revision:	37
Committed:	Mon Feb 15 14:44:25 2016 UTC (8 years, 2 months ago) by tony
Content type:	text/x-pascal
File size:	7429 byte(s)
Log Message:	Committing updates for Release R1-4-0
#	Content
1	(*
2	* IBX For Lazarus (Firebird Express)
3	*
4	* The contents of this file are subject to the Initial Developer's
5	* Public License Version 1.0 (the "License"); you may not use this
6	* file except in compliance with the License. You may obtain a copy
7	* of the License here:
8	*
9	* http://www.firebirdsql.org/index.php?op=doc&id=idpl
10	*
11	* Software distributed under the License is distributed on an "AS
12	* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
13	* implied. See the License for the specific language governing rights
14	* and limitations under the License.
15	*
16	* The Initial Developer of the Original Code is Tony Whyman.
17	*
18	* The Original Code is (C) 2014 Tony Whyman, MWA Software
19	* (http://www.mwasoftware.co.uk).
20	*
21	* All Rights Reserved.
22	*
23	* Contributor(s): ______________________________________.
24	*
25	*)
26	unit IBXUpgradeConfFile;
27
28	{$mode objfpc}{$H+}
29
30	{
31	TUpgradeConfFile encapsulated a text file in “ini” file format with
32	the following sections:
33
34	[status]
35
36	This should have a single named value “current” giving the current database
37	schema number as in integer e.g.
38
39	current = 2
40
41	This should normally be set to the same value as the RequiredVersionNo property
42	and acts as a check to ensure that both are in sync.
43
44	[Version.nnn]
45
46	Where nnn is an integer with leaving zeroes. For example, “Version.002” is
47	the section read to upgrade the database schema from version 1 to version 2.
48	This section can contain the following named values:
49
50	Name Type Use
51
52	Upgrade String Name and optional path to SQL script used to perform
53	the upgrade. May either be absolute path or relative
54	to the upgrade configuration file. Either forwards or
55	back slashes may be used as the path delimiter.
56
57	Msg string Text message displayed in progress dialog while script is
58	active. Defaults to “Upgrading Database Schema to Version nnn”.
59
60	BackupDatabase yes/no If present and set to “yes” then a database backup in
61	gbak format is made before the upgrade is performed. The backup file is
62	located in the same directory as the database file and is given the same
63	name as the database file with the extension replaced with “.nnn.gbak”.
64	Where “nnn” is the current schema version number (i.e. prior to running
65	the upgrade script).
66
67	<Parameter Name> string Name and optional path to binary data file. May either be
68	absolute path or relative to the upgrade configuration file.
69	Either forwards or back slashes may be used as the path delimiter.
70
71
72	For example:
73
74	[Version.002]
75	Msg = Upgrading to Version 2
76	BackupDatabase = yes
77	Upgrade = patches/02-patch.sql
78	mugshot = images/man.png.gz
79
80	Note that in the above, “mugshot” is intended to be used to resolve an Update,
81	Insert or Delete query parameter in the 02-patch.sql file. E.g.
82
83	Update EMPLOYEE Set Photo =:MUGSHOT Where Emp_no = 2;
84
85	This is only applicable to BLOB columns and the above is interpreted as update
86	the EMPLOYEE table where the Emp_no is “2” and set the value of the Photo column
87	to the binary data contained in the file “images/man.png.gz”.
88	}
89
90	interface
91
92	uses
93	Classes, SysUtils, IniFiles;
94
95	type
96	TUpgradeInfo = record
97	UpdateSQLFile,
98	UserMessage: string;
99	BackupDB: boolean;
100	end;
101
102	{ TUpgradeConfFile }
103
104	TUpgradeConfFile = class
105	private
106	FConfFileName: string;
107	FCurrentVersion: string;
108	FUpgradeInfo: TIniFile;
109	function GetUpgradeAvailableToVersion: integer;
110	public
111	constructor Create(aFileName: string);
112	destructor Destroy; override;
113	class function IsAbsolutePath(aPath: string): boolean;
114	function CheckUpgradeAvailable(RequiredVersionNo: integer): boolean;
115	function GetUpgradeInfo(VersionNo: integer; var UpgradeInfo: TUpgradeInfo): boolean;
116	function GetSourceFile(aName: string; var FileName: string): boolean;
117	property UpgradeAvailableToVersion: integer read GetUpgradeAvailableToVersion;
118	end;
119
120	EUpgradeConfFileError = class(Exception);
121
122
123	implementation
124
125	const
126	sSectionheader = 'Version.%.3d';
127
128	resourcestring
129	sInvalidConfFile = 'Database Upgrade Required, but the Upgrade File (%s) is missing or not specified';
130	sUpgradeRequired = 'Database Upgrade Required, but the Upgrade File is out of Date. '+
131	'Required Version = %d, Upgrade available for version %d';
132	sNoInfo = 'Upgrading Database Schema to Version %d';
133
134	{ TUpgradeConfFile }
135
136	function TUpgradeConfFile.GetUpgradeAvailableToVersion: integer;
137	begin
138	Result := StrToInt(FUpgradeInfo.ReadString('Status','Current','0'))
139	end;
140
141	constructor TUpgradeConfFile.Create(aFileName: string);
142	begin
143	inherited Create;
144	FConfFileName := aFileName;
145	if (FConfFileName = '') or not FileExists(FConfFileName) then
146	raise EUpgradeConfFileError.CreateFmt(sInvalidConfFile,[FConfFileName]);
147	FUpgradeInfo := TIniFile.Create(FConfFileName);
148	end;
149
150	destructor TUpgradeConfFile.Destroy;
151	begin
152	if assigned(FUpgradeInfo) then FUpgradeInfo.Free;
153	inherited Destroy;
154	end;
155
156	class function TUpgradeConfFile.IsAbsolutePath(aPath: string): boolean;
157	begin
158	Result := false;
159	{$IFDEF WINDOWS}
160	Result := (ExtractFileDrive(aPath) <> '') or
161	((Length(aPath) > 0) and (aPath[1] = DirectorySeparator));
162	{$ENDIF}
163	{$IFDEF UNIX}
164	Result := (Length(aPath) > 0) and (aPath[1] = DirectorySeparator);
165	{$ENDIF}
166	end;
167
168	function TUpgradeConfFile.CheckUpgradeAvailable(RequiredVersionNo: integer
169	): boolean;
170	var CurVersion: integer;
171	begin
172	CurVersion := GetUpgradeAvailableToVersion;
173	if CurVersion < RequiredVersionNo then
174	raise EUpgradeConfFileError.CreateFmt(sUpgradeRequired, [RequiredVersionNo,CurVersion]);
175	end;
176
177	function TUpgradeConfFile.GetUpgradeInfo(VersionNo: integer;
178	var UpgradeInfo: TUpgradeInfo): boolean;
179	begin
180	Result := false;
181	FCurrentVersion := Format(sSectionheader,[VersionNo]);
182	UpgradeInfo.UserMessage := FUpgradeInfo.ReadString(FCurrentVersion,'Msg',
183	Format(sNoInfo,[VersionNo]));
184	UpgradeInfo.UpdateSQLFile := FUpgradeInfo.ReadString(FCurrentVersion,'Upgrade','');
185	Result := UpgradeInfo.UpdateSQLFile <> '';
186	if Result then
187	begin
188	DoDirSeparators(UpgradeInfo.UpdateSQLFile); {Resolve Platform dependencies}
189	if not IsAbsolutePath(UpgradeInfo.UpdateSQLFile) then
190	UpgradeInfo.UpdateSQLFile := ExtractFilePath(FConfFileName) + UpgradeInfo.UpdateSQLFile;
191	UpgradeInfo.BackupDB := CompareText(FUpgradeInfo.ReadString(FCurrentVersion,'BackupDatabase','no'),'yes') = 0;
192	Result := FileExists(UpgradeInfo.UpdateSQLFile);
193	end;
194	end;
195
196	function TUpgradeConfFile.GetSourceFile(aName: string; var FileName: string
197	): boolean;
198	begin
199	FileName := FUpgradeInfo.ReadString(FCurrentVersion,aName,'');
200	DoDirSeparators(FileName);
201	if not IsAbsolutePath(FileName) then
202	FileName := ExtractFilePath(FConfFileName) + FileName;
203	Result := FileExists(FileName);
204	end;
205
206	end.
207