MobiLink Event pseudo code

 

 

------------------------------------------------------
MobiLink complete event model.
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Legend:
- // This is a comment.
- <name>
    The pseudo code for <name> is listed separately
    in a later section, under a banner:
        ------------------------
        name
        ------------------------
- VariableName <- value
    Assign the given value to the given variable name.
    Variable names are in mixed case.
- event_name
    If you have defined a script for the given event name,
    it will be invoked.
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CONNECT to consolidated database
begin_connection_autocommit
begin_connection
COMMIT
for each synchronization request with
     the same script version {
  <synchronize>
}
end_connection
COMMIT
DISCONNECT from consolidated database

 

------------------------------------------------------
synchronize
------------------------------------------------------

 

<authenticate>
<begin_synchronization>
<upload>
<prepare_for_download>
<download>
<end_synchronization>

 

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authenticate
------------------------------------------------------

 

Status <- 1000
UseDefaultAuthentication <- TRUE
if( authenticate_user script is defined ) {
  UseDefaultAuthentication <- FALSE
  TempStatus <- authenticate_user
  if( TempStatus > Status ) {
    Status <- TempStatus
  }
}

 

if( authenticate_user_hashed script is defined ) {
  UseDefaultAuthentication <- FALSE
  TempStatus <- authenticate_user_hashed
  if( TempStatus > Status ) {
    Status <- TempStatus
  }
}
  if( authenticate_parameters script is defined )
 {
    TempStatus <- authenticate_parameters
    if( TempStatus > Status ) {
      Status <- TempStatus
  }

 

if( UseDefaultAuthentication ) {
  if( the user exists in the ml_user table ) {
    if( ml_user.hashed_password column is not NULL ) {
      if( password matches ml_user.hashed_password ) {
        Status <- 1000
      } else {
        Status <- 4000
      }
    } else {
      Status <- 1000
    }
  } else if( -zu+ was on the command line ) {
    Status <- 1000
  } else {
    Status <- 4000
  }
}
if( Status >= 3000 ) {
  // Abort the synchronization.
} else {
  // UserName defaults to MobiLink user name
  // sent from the remote.
  if( modify_user script is defined ) {
    UserName <- modify_user
    // The new value of UserName is later passed to
    // all scripts that expect the MobiLink user name.
  }
}
COMMIT

 

------------------------------------------------------
begin_synchronization
------------------------------------------------------

 

begin_synchronization   // Connection event.
for each table being synchronized {
    begin_synchronization    // Call the table level script.
}
for each publication being synchronized {
  begin_publication
}
COMMIT

 

------------------------------------------------------
end_synchronization
------------------------------------------------------

 

for each publication being synchronized {
  if( begin_publication script was called ) {
    end_publication
  }
}
for each table being synchronized {
  if( begin_synchronization table script was called ) {
    end_synchronization // Table event.
  }
}
if( begin_synchronization table script was called ) {
  end_synchronization     // Connection event.
}
for each table being synchronized {
synchronization_statistics // Table event.
}
synchronization_statistics // Connection event.
for each table being synchronized {
  time_statistics // Table event.
}
time_statistics // Connection event.

 

COMMIT
======================================================
------------------------------------------------------
Events during uploadThe following pseudocode illustrates
how upload events and upload scripts are invoked.
These events take place at the upload location in the
complete event model. See Overview of MobiLink events.
Overview of the upload
------------------------------------------------------
upload
------------------------------------------------------
begin_upload // Connection event
for each table being synchronized {
  begin_upload // Table event
}
  handle_UploadData
  for each table being synchronized {
    begin_upload_rows
    for each uploaded INSERT or UPDATE for this table {
      if( INSERT ) {
        <upload_inserted_row>
      }
      if( UPDATE ) {
        <upload_updated_row>
      }
    }
    end_upload_rows
  }
  for each table being synchronized IN REVERSE ORDER {
    begin_upload_deletes
    for each uploaded DELETE for this table {
      <upload_deleted_row>
    }
    end_upload_deletes
  }
 
For each table being synchronized {
  if( begin_upload table script is called ) {
    end_upload // Table event
  }
}
if( begin_upload connection script was called ) {
  end_upload // Connection event

 

  for each table being synchronized {
    upload_statistics  // Table event.
  }
    upload_statistics  // Connection event.

 

  COMMIT
Upload inserts
------------------------------------------------------
<upload_inserted_row>
------------------------------------------------------
// NOTES:
// - Only table scripts for the current table are involved.

 

  ConflictsAreExpected <- (
       upload_new_row_insert script is defined
    or upload_old_row_insert script is defined
    or resolve_conflict script is defined )
  if( upload_insert script is defined ) {
    upload_insert
  } else if( ConflictsAreExpected
      and upload_update script is not defined
      and upload_insert script is not defined
      and upload_delete script is not defined ) {
      // Forced conflict.
      upload_new_row_insert
      resolve_conflict
  } else {
      // Ignore the insert.
  }

 

Upload updates
------------------------------------------------------
upload_updated_row
------------------------------------------------------
// NOTES:
// - Only table scripts for the current table are involved.
// - Both the old (original) and new rows are uploaded for
//   each update.

 

  ConflictsAreExpected <- (
       upload_new_row_insert script is defined
    or upload_old_row_insert script is defined
    or resolve_conflict script is defined )
  Conflicted <- FALSE
  if( upload_update script is defined ) {
    if( ConflictsAreExpected
      and upload_fetch script is defined ) {
      FETCH using upload_fetch INTO current_row
      if( current_row <> old row ) {
        Conflicted <- TRUE
      }
    }
    if( not Conflicted ) {
      upload_update
    }
  } else if( upload_update script is not defined
      and upload_insert script is not defined
      and upload_delete script is not defined ) {
      // Forced conflict.
      Conflicted <- TRUE
  }
  if( ConflictsAreExpected and Conflicted ) {
    upload_old_row_insert
    upload_new_row_insert
    resolve_conflict
  }

 

Upload deletes
------------------------------------------------------
upload_deleted_row
------------------------------------------------------
// NOTES:
// - Only table scripts for the current table are involved.

 

  ConflictsAreExpected <- (
       upload_new_row_insert script is defined
    or upload_old_row_insert script is defined
    or resolve_conflict script is defined )
  if( upload_delete is defined ) {
    upload_delete
  } else if( ConflictsAreExpected
    and upload_update script is not defined
    and upload_insert script is not defined
    and upload_delete script is not defined ) {
    // Forced conflict.
    upload_old_row_insert
    resolve_conflict
  } else {
    // Ignore this delete.
  }

 

=========================================================
------------------------------------------------------
prepare_for_download
------------------------------------------------------

 

modify_last_download_timestamp
prepare_for_download
if( modify_last_download_timestamp script is defined
    or prepare_for_download script is defined ) {
    COMMIT
}
------------------------------------------------------
download
------------------------------------------------------

 

begin_download
begin_download // Connection event.
for each table being synchronized {
   begin_download // Table event.
}
   handle_DownloadData
   for each table being synchronized {
     begin_download_deletes
     for each row in download_delete_cursor {
       if( all primary key columns are NULL ) {
         send TRUNCATE to remote
       } else {
         send DELETE to remote
       }
     }
     end_download_deletes
     begin_download_rows
     for each row in download_cursor {
       send INSERT ON EXISTING UPDATE to remote
     }
     end_download_rows
   }
   modify_next_last_download_timestamp
   for each table being synchronized {
     if( begin_download table script is called ) {
        end_download // Table event
     }
}
if( begin_download connect script is called ) {
   end_download // Connection event
}
   for each table being synchronized {
     download_statistics   // Table event.
   }
     download_statistics   // Connection event.

 

COMMIT