src/apps/haikudepot/server/AbstractServerProcess.h

   1 /*
   2  * Copyright 2017, Andrew Lindesay <apl@lindesay.co.nz>.
   3  * All rights reserved. Distributed under the terms of the MIT License.
   4  */
   5
   6 #ifndef ABSTRACT_SERVER_PROCESS_H
   7 #define ABSTRACT_SERVER_PROCESS_H
   8
   9 #include <HttpRequest.h>
  10 #include <Json.h>
  11 #include <String.h>
  12 #include <Url.h>
  13
  14 #include "StandardMetaData.h"
  15 #include "Stoppable.h"
  16
  17
  18 #define APP_ERR_NOT_MODIFIED            (B_APP_ERROR_BASE + 452)
  19 #define APP_ERR_NO_DATA                         (B_APP_ERROR_BASE + 453)
  20
  21
  22 typedef enum process_options {
  23         SERVER_PROCESS_NO_NETWORKING    = 1 << 0,
  24         SERVER_PROCESS_PREFER_CACHE             = 1 << 1,
  25         SERVER_PROCESS_DROP_CACHE               = 1 << 2
  26 } process_options;
  27
  28
  29 typedef enum process_state {
  30         SERVER_PROCESS_INITIAL                  = 1,
  31         SERVER_PROCESS_RUNNING                  = 2,
  32         SERVER_PROCESS_COMPLETE                 = 3
  33 } process_state;
  34
  35
  36 /*! Clients are able to subclass from this 'interface' in order to accept
  37     call-backs when a process has exited; either through success or through
  38     failure.
  39  */
  40
  41 class AbstractServerProcessListener {
  42 public:
  43         virtual void                            ServerProcessExited() = 0;
  44 };
  45
  46
  47 class AbstractServerProcess : public Stoppable {
  48 public:
  49                                                                 AbstractServerProcess(
  50                                                                         AbstractServerProcessListener* listener,
  51                                                                         uint32 options);
  52         virtual                                         ~AbstractServerProcess();
  53
  54         virtual const char*                             Name() = 0;
  55                         status_t                        Run();
  56                         status_t                        Stop();
  57                         status_t                        ErrorStatus();
  58                         bool                            IsRunning();
  59                         bool                            WasStopped();
  60
  61 protected:
  62         virtual status_t                        RunInternal() = 0;
  63         virtual status_t                        StopInternal();
  64
  65         virtual void                            GetStandardMetaDataPath(
  66                                                                         BPath& path) const = 0;
  67         virtual void                            GetStandardMetaDataJsonPath(
  68                                                                         BString& jsonPath) const = 0;
  69
  70                         status_t                        IfModifiedSinceHeaderValue(
  71                                                                         BString& headerValue) const;
  72                         status_t                        IfModifiedSinceHeaderValue(
  73                                                                         BString& headerValue,
  74                                                                         const BPath& metaDataPath,
  75                                                                         const BString& jsonPath) const;
  76
  77                         status_t                        PopulateMetaData(
  78                                                                         StandardMetaData& metaData,
  79                                                                         const BPath& path,
  80                                                                         const BString& jsonPath) const;
  81
  82                         status_t                        ParseJsonFromFileWithListener(
  83                                                                         BJsonEventListener *listener,
  84                                                                         const BPath& path) const;
  85
  86                         status_t                        DownloadToLocalFileAtomically(
  87                                                                         const BPath& targetFilePath,
  88                                                                         const BUrl& url);
  89
  90                         status_t                        DeleteLocalFile(const BPath& currentFilePath);
  91
  92                         status_t                        MoveDamagedFileAside(
  93                                                                         const BPath& currentFilePath);
  94
  95                         bool                            HasOption(uint32 flag);
  96                         bool                            ShouldAttemptNetworkDownload(
  97                                                                         bool hasDataAlready);
  98
  99         static  bool                            IsSuccess(status_t e);
 100
 101 private:
 102                         BLocker                         fLock;
 103                         AbstractServerProcessListener*
 104                                                                 fListener;
 105                         bool                            fWasStopped;
 106                         process_state           fProcessState;
 107                         status_t                        fErrorStatus;
 108                         uint32                          fOptions;
 109
 110                         BHttpRequest*           fRequest;
 111
 112                         process_state           ProcessState();
 113                         void                            SetErrorStatus(status_t value);
 114                         void                            SetProcessState(process_state value);
 115
 116                         status_t                        DownloadToLocalFile(
 117                                                                         const BPath& targetFilePath,
 118                                                                         const BUrl& url,
 119                                                                         uint32 redirects, uint32 failures);
 120
 121                         bool                            LooksLikeGzip(const char *pathStr) const;
 122
 123 };
 124
 125 #endif // ABSTRACT_SERVER_PROCESS_H