2009-06-28 26 views
30

mi aplicación tiene que tratar con información del calendario (incluso ocurrencia única, recurrencia, etc.). Para poder interactuar fácilmente con otras aplicaciones, pensé que sería una buena idea crear mi esquema de base de datos basado en el formato de iCalendar (campos, relaciones, restricciones) directamente para obtener objetos compatibles con iCalendar a través de ORM que puedo exponer fácilmente cuando necesario.iCalendar Lista de "campos" (para el esquema de base de datos basado en el estándar iCalendar)

Sé que el RFC está disponible, pero es un poco complicado debido a toda la información adicional que no uso en este momento.

¿Podría alguien indicarme una fuente más fácil para crear un esquema de base de datos basado en el estándar iCal (es decir, una lista de campos/nombres de campo y su relación para las entradas de iCal)?

Gracias!

Respuesta

40

He hecho esto (solo para VEvents, no es compatible con elementos TODO ni entradas del diario ni nada de eso). Mi aplicación es el siguiente (después de quitar las columnas que no son específicos de la pregunta):

-- One table for each event. An event may have multiple rRules. 
Create Table [vEvent] 
    (vEventID Integer Identity(1, 1) Not Null 
    Constraint [vEvent.pk] 
    Primary Key 
    Clustered 
    ,title nVarChar(200) Not Null); 

-- One table for rRules. 
-- My application does NOT support the "bySetPos" rule, so that is not included. 
Create Table [rRule] 
    (rRuleID Integer Identity(1, 1) Not Null 
    Constraint [rRule.pk] 
    Primary Key 
    Clustered 
    ,vEventID Integer Not Null 
    Constraint [fk.vEvent.rRules] 
    Foreign Key 
    References [vEvent] (vEventID) 
    On Update Cascade 
    On Delete Cascade 
    ,[class]   varChar( 12) Not Null Default('public') 
    ,[created]   DateTime  Not Null Default(getUTCDate()) 
    ,[description]  nVarChar(max)  Null 
    ,[dtStart]   DateTime  Not Null 
    ,[dtEnd]   DateTime   Null 
    ,[duration]   varChar( 20)  Null 
    ,[geoLat]   Float    Null 
    ,[geoLng]   Float    Null 
    ,[lastModified] DateTime  Not Null Default(getUTCDate()) 
    ,[location]  nVarChar(max)  Null 
    ,[organizerCN]  nVarChar( 50)  Null 
    ,[organizerMailTo] nVarChar(100)  Null 
    ,[seq]    Integer  Not Null Default(0) 
    ,[status]   varChar( 9) Not Null Default('confirmed') 
    ,[summary]   nVarChar( 75)  Null 
    ,[transparent]  Bit   Not Null Default(0) 
    ,[freq]    varChar( 8) Not Null Default('daily') 
    ,[until]   DateTime   Null 
    ,[count]   Integer   Null 
    ,[interval]  Integer  Not Null Default(1) 
    ,[bySecond]   varChar(170)  Null 
    ,[byMinute]   varChar(170)  Null 
    ,[byHour]   varChar( 61)  Null 
    ,[byDay]   varChar( 35)  Null 
    ,[byMonthDay]  varChar(200)  Null 
    ,[byYearDay]  varChar(3078)  Null 
    ,[byWeekNo]   varChar(353)  Null 
    ,[byMonth]   varChar( 29)  Null 
    ,[wkSt]    Char ( 2)  Null Default('mo')); 

-- Class must be one of "Confidential", "Private", or "Public" 
Alter Table [rRule] 
Add Constraint [rRule.ck.Class] 
Check ([class] In ('confidential', 'private', 'public')); 

-- Start date must come before End date 
Alter Table [rRule] 
Add Constraint [rRule.ck.dtStart] 
Check ([dtEnd] Is Null Or [dtStart] <= [dtEnd]); 

-- dtEnd and duration may not both be present 
Alter Table [rRule] 
Add Constraint [rRule.ck.duration] 
Check (Not ([dtEnd] Is Not Null And [duration] Is Not Null)); 

-- Check valid values for [freq]. Note that 'single' is NOT in the RFC; 
-- it is an optimization for my particular iCalendar calculation engine. 
-- I use it as a clue that this pattern has only a single date (dtStart), 
-- and there is no need to perform extra calculations on it. 
Alter Table [rRule] 
Add Constraint [rRule.ck.freq] 
Check ([freq] In 
    ('yearly' 
    ,'monthly' 
    ,'weekly' 
    ,'daily' 
    ,'hourly' 
    ,'minutely' 
    ,'secondly' 
    ,'single')); -- Single is NOT part of the spec! 

-- If there is a latitude, there must be a longitude, and vice versa. 
Alter Table [rRule] 
Add Constraint [rRule.ck.geo] 
Check (([geoLat] Is Null And [geoLng] Is Null) 
     Or ([geoLat] Is Not Null And [geoLng] Is Not Null)); 

-- Interval must be positive. 
Alter Table [rRule] 
Add Constraint [rRule.ck.interval] 
Check ([interval] > 0); 

-- Status has a set of defined values. 
Alter Table [rRule] 
Add Constraint [rRule.ck.status] 
Check ([status] In ('cancelled', 'confirmed', 'tentative')); 

-- Until and Count may not coexist in the same rule. 
Alter Table [rRule] 
Add Constraint [rRule.ck.until and count] 
Check (Not ([until] Is Not Null And [count] Is Not Null)); 


-- One table for exceptions to rRules. In my application, this covers both 
-- exDate and rDate. I do NOT support extended rule logic here; The RFC says 
-- you should support the same sort of date calculations here as are supported 
-- in rRules: exceptions can recur, etc. I don't do that; mine is simply a 
-- set of dates that are either "exceptions" (dates which don't appear, even 
-- if the rule otherwise says they should) or "extras" (dates which do appear, 
-- even if the rule otherwise wouldn't include them). This has proved 
-- sufficient for my application, and something that can be exported into a 
-- valid iCalendar file--even if I can't import an iCalendar file that makes 
-- use of recurring rules for exceptions to recurring rules. 
Create Table [exDate] 
    (exDateID Integer Identity(1, 1) Not Null 
    Constraint [exDate.pk] 
    Primary Key 
    Clustered 
    ,rRuleID Integer Not Null 
    Constraint [fk.rRule.exDates] 
    Foreign Key 
    References [rRule] (rRuleID) 
    On Update Cascade 
    On Delete Cascade 
    ,[date] DateTime Not Null 
    ,[type] varChar(6) Not Null); -- Type = "exDate" or "rDate" for me; YMMV. 

Para ir junto con esto, tengo varias funciones CLR de SQL Server 2005 + que se pueden utilizar para calcular las fechas para varios eventos. He encontrado los siguientes formularios para ser muy útil:

Select * From dbo.getDatesByVEventID(@id, @startDate, @endDate) 
Select * From dbo.getEventsByDateRange(@startDate, @endDate, @maxCount) 

Implementación de lo anterior es muy divertido de descubrir!

+0

Sé que esto es más de 7 años de edad, es esto todavía cómo acercarse a este, Y hace más nueva versión de SQL darle ninguna opción mejor que consultan? –

0

iCal es una aplicación de Apple que sigue el estándar actualmente conocido como Icalendar (el sucesor del anterior Vcalendar). Creo que la wikipedia entry tiene toda la información que necesita para sus propósitos, y en un formato simple y fácil de seguir, pero, ¡siéntase libre de pedir más ayuda si es necesario!

12

Sí, más o menos. Sunbird (el calendario opensource de mozilla) está basado en sqlite y acabo de descargar y descomprimir su código fuente. Tiene archivos .sql en él.

ftp://ftp.mozilla.org/pub/mozilla.org/calendar/sunbird/releases/0.9/source/

Mozilla \ \ calendario proveedores \ --Este de almacenamiento \ esquema 7.sql es el esquema que utiliza Sunbird Para que los archivos de iCal válidos, por lo que no puede ser tan malo.

1
+2

Nota para los visitantes nuevos: El enlace de la documentación del desarrollador de Apple ya no funciona. –

+1

http: //www.filibeto.org/unix/macos/lib/dev/documentation/AppleApplications/Reference/SyncServicesSchemaRef/SyncServicesSchemaRef.pdf – Slartibartfast

1

Muchas gracias Chris Nielsen por su excelente solución anterior. Sin embargo, tuve algunos problemas con él, así que lo modifiqué. Tenga en cuenta que la solución anterior está en Python sqlalchemy. Lo convertiré muy pronto.

My main difficulties with Chris's solution (and they might not apply to everyone) are 

(1) I didn't need many of the columns in his solution. I only needed columns which would help me with Events and Recurrences. This is the fault of the iCalendar spec, not Chris's. My solution below only considers recurrence rules in terms of their calendar restrictions and their sequence restrictions. 

(2) Certain columns -- most importantly dtStart and dtEnd -- belong to VEVENT, not to RRULE, but Chris placed them in RRULE. This was confusing to me. 
VEVENT: https://tools.ietf.org/html/rfc5545#section-3.6.1 
RRULE: https://tools.ietf.org/html/rfc5545#section-3.3.10 
(3) I also needed to figure out how to contain a schedule which might have a variety of patterns. For example, an event might happen every week on Friday from 6PM-9PM but also all day on May Day. This requires flexibility with dtStart and dtEnd. For this reason, I created a containing Table "SCHEDULE" which maintains a many-to-many relationship with EVENTS, whereas EVENTS have a containment relationship with RRULES. 

Below is my solution in sqlalchemy. I will convert this to SQL ASAP. 

=============================================================== 

from app import db 
from sqlalchemy import CheckConstraint 
from sqlalchemy.ext.associationproxy import association_proxy 


class Schedule(db.Model): 
    id = db.Column(db.Integer, primary_key=True) 
    subtypes_relation = db.relationship('Event', secondary=schedule_event_association, 
             backref=db.backref('Schedule', lazy='dynamic')) 

schedule_event_association = db.Table(
    'schedule_event_association', 
    db.Column('schedule_id', db.Integer, db.ForeignKey('schedule.id')), 
    db.Column('event_id', db.Integer, db.ForeignKey('event.id'))) 

class Event(db.Model): 
    id = db.Column(db.Integer, primary_key=True) 
    dt_start = db.Column(db.DateTime) # start time 
    dt_end = db.Column(db.DateTime) # end time 
    tz_id = db.Column(db.String) # Time Zone 

    recurrence_rule = db.Column('RecurrenceRule_id', db.Integer, db.ForeignKey('RecurrenceRule.id')) 

# Start date must come before End date 
    CheckConstraint('dtEnd is NULL OR dtStart <= dtEnd', name='Valid: Time Period') 

class RecurrenceRule(db.Model): 
    id = db.Column(db.Integer, primary_key=True) 

    # Frequency Type 
    freq = db.Column(db.String(8), nullable=False, default='weekly') # type of recurrence 

    # Calendar-Based Rules 
    byDay = db.Column(db.String(35)) # List of Day of the Week 
             # "mo,tu,we" for weekly 
             # "+2MO, -1MO" = second monday, last monday for yearly or monthly 
    byMonthDay = db.Column(db.String(200)) # List of Day of the Month 
              # +1,-1" 
              # Only for Monthly or Yearly 
    byYearDay = db.Column(db.String(3078)) # List Day of the Year 
              #"+1, -1" 
              # Only for yearly 
              # Take care with leap years 
    byWeekNo = db.Column(db.String(353)) # Which week of Mon`enter code here`th 
              # "+5, -3" for fifth and third-to-last 
              # Only for yearly 
    byMonth = db.Column(db.String(29)) # Month of year. 

    # Sequence-Based Rules 
    until = db.Column(db.DateTime) # last day of occurence 
    count = db.Column(db.Integer) # number of occurences 
    interval = db.Column(db.Integer, nullable=False, default=1) # interval between recurrences 
    bysetpos = db.Column(db.String()) # Specifies specific instances of recurrence 


# Valid Values 
    CheckConstraint(freq in ('yearly', 'monthly', 'weekly', 'daily', 'single'), 
        name='Valid: Frequency Value') 
    CheckConstraint(interval > 0, name='Valid: Positive Interval') 
    CheckConstraint(byDay is not None and freq in ('daily', 'yearly', 'monthly')) 
    CheckConstraint(byWeekNo is not None and freq in ('yearly', 'monthly')) 
    CheckConstraint(byYearDay is not None and freq == 'yearly') 

# Until and Count may not coexist in the same rule. 
    CheckConstraint(not (until is not None and count is not None), 
        name='Valid: Not Both Until and Count') 
+0

¿Fue capaz de crear SQL para esto? Estoy trabajando en un problema similar y me gustaría obtener alguna guía para el SQL. – aran

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