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, 9 months ago) by tony
Content type:	text/x-pascal
File size:	7429 byte(s)
Log Message:	Committing updates for Release R1-4-0
#	User	Rev	Content
1	tony	37	(*
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