jm-lemmi / ical-relay

Relay ical urls and edit them on the fly with different modules.

Julian Lemmerich

• 🏫 I study Cyber Security at DHBW-Mannheim.
• 🏢 Working at Cirosec in Heilbronn.
• 👨🏼‍💻 Hacking at DU4L CTF Team.
• 📫 [email protected]

ical-relay's Issues

Use `AddVEvent`

Convert to using AddVEvent, after time-parsing has been merged to upstream

This gets rid of the whole loop for copying the items and may also get rid of the restriction in elements to copy from #8

func (calendar *Calendar) AddVEvent(e *VEvent)

Fix from #23 removes elements that should not be removed

ranging over array while removing is not good. removes elements that should not be removed

ical-relay/handlers.go

Lines 62 to 86 in ae2052c

	for i, component := range calendar.Components {
	// this is a hack to get around the fact that the ical library doesn't provide a way to remove an event
	switch component.(type) {
	case *ics.VEvent:
	event := component.(*ics.VEvent)
	// extract summary and time from original event
	summary := event.GetProperty(ics.ComponentPropertySummary).Value
	date, _ := event.GetStartAt()
	id := event.Id()
	// check if one of the profiles regex's matches summary
	if date.After(profile.From) && profile.Until.After(date) {
	for _, excludeRe := range profile.RegEx {
	if excludeRe.MatchString(summary) || excludeRe.MatchString(id) {
	// remove event from calendar
	remove(calendar.Components, i)
	excludedEvents++
	requestLogger.Debugf("Excluding event '%s' with id %s\n", summary, id)
	continue
	}
	}
	}
	default:
	continue
	}
	}

This regards both v0.4.1 and v1.0.0-dev1

edit existing calendar instead of copying to new calendar

Das kann im Zuge von #20 gemacht werden.

Sollte dann auch DU4L/ical-relay#6 fixen.

Reuse Filter for a list of URLs/Profiles

For example filter all "entfällt" for the list of all dhbw courses

[edit-bysummary-regex] move by time

Instead of setting the new time, move the event, for example by 15 minutes back. Otherwise moving multiple events back is not possible

[Module] Write to file

The module saves the current ical to a file. Allows archiving.

Package for distribution

• docker image
• deb, rpm
• linux binary

Since there are no dependencies and no complicated install, this should not be very hard

`VTodo` not filtered by `removeByRegexSummaryAndTime`

Only VEvent are filtered

https://raw.githubusercontent.com/arran4/golang-ical/master/testdata/rfc5545sec4/input3.ics

INFO[0000] Finding box templates                        
INFO[0002] Client-addr: 127.0.0.1:40108                  request=e2f66547-1daa-4139-b215-746996fd78b1
DEBU[0002] Requested Module: delete-bysummary-regex     
DEBU[0002] Component type: *ics.VTodo

[Source] E-Mail.

Google and MS compatibility mode

If possible. They have both implemented similar features in a proprietary way. It should be possible to translate between those as good as possible. Not everything can be done.

[Module] Eliminate Duplicates

This should be a bool setting

WebUI

• Setting up E-Mail reminders #34
• Finding public calendars JM-Lemmi/ical-relay-frontend#1
• Viewing calendar preview
• Generating customized URLs #44

[Module] repeating events

CalDAV/DAVx5 Endpoint

Subtask of #37.

Kann es möglicherweise ersetzen, oder es ist eine übertriebene Schnapsidee...

Hier erstmal Ideen sammeln.

[Module] Edit Entry Description/Location by summary

Send E-Mail Invites for calendar entries

To circumvent Outlooks limitation of not importing into the main calendar, the server could send E-Mails with the calendar entries as ics, which would then appear in the Main calendar.

Fix GH-Actions

Publish with the correct tags on every commit in main as well as in dev

remove hardcoded Paths

Exclude by UID

[Module] Mirror Rules of profile

[Module: delete-duplicates] is deleting too much

It seems that delete-duplicates is deleting events that are not actually duplicates of each other.

Convert to yaml

I'm more used to yml.

#20 depends on this

Only include the next possible Entry for repeating entries

As an Admin I want to be able to reduce RRULE events to a single non-repeating event only showing the next possible entry

Differentiate additional Entries by Profile

I propose to name the ics file after the profile. This also avoids double adding the ics when using multiple profiles

Periodically E-Mail filterresults

Periodically E-Mailing diff between original and edited to check if entries are filtered that should not be.

Bidirectional communication

To enable editing from external, like Outlook

For example with CalDAV if thats possible?

Add manual Entries

Frontend Rendering the Calendar

Idea: Render the initial week on the server, fetching the rest of the ical with javascript, so that the current week is instantly available but requests are kept to a minimum.

Edit matched Entries

This could actually be accomplished by a combination of #3 and #4.

[Module: delete-duplicates] combine multiple entries, if they differ

if the description or other components of a duplicate differ, it should combine them

Switch to arran4 fork of golang-ical

Waiting for merge of Issue 52

Combine multiple external sources into one

[Action] Strip information with different levels

(like Outlook ics export options)

[Monitoring] Notify changes per Mail

This could be in conjuction #33. Compare to file and send diff to Mail.

View: compare original with edited calendar

For Admins (?) there should be a way to see the differences between the edited and unedited calendar. This should be possible with the compare function.

Admin API

• add/remove module to profile
• replace whole config

Clone organizer, uuid and attendee to new calendar entry

ical-relay/handlers.go

Lines 103 to 108 in df6fc05

	// exclude organizer, uuid, attendee property due to broken escaping
	for _, property := range event.Properties {
	if (property.IANAToken != string(ics.ComponentPropertyOrganizer)) && (property.IANAToken != string(ics.ComponentPropertyUniqueId) && (property.IANAToken != string(ics.ComponentPropertyAttendee))) {
	newEvent.Properties = append(newEvent.Properties, property)
	}
	}

[Modul: edit-bysummary - add-time] Duplicates entstehen mit Immutable History

Passthrough ID

Restructure different edit modes

Instead of having to combine multiple filters with multiple profiles chained in a row, the system should accept an "array" of modifiers. Each modifier then has a "mode" and additional arguments that mode needs. An example configuration should look like this:

profiles:
   abc:
      url: "https://example.com/calendar.ics"
      passid: true
      modifiers:
      - mode: regex
        regex: "testentry"
        from: "2021-12-02T00:00:00Z"
        until: "2021-12-31T00:00:00Z"
      - mode: delete-id
        id: "testidacb@calendar"
      - mode: add
        url: "https://othersource.com/othercalendar.ics"
      - mode: deduplicate
      - mode: delete
        from: "2019-01-01T00:00:00Z"
        until: "2019-12-31T23:59:59Z"

this would enable more modularity for different filtering methods as well as faster processing times.

Per Profile URL

[Module] Immutable Past

Instead of using the workaround just have a bool config for each profile, that enables immutable past. This should also be less prone to errors.

edit-Modules panic when non-existent property is edited

at least this is the bug, I think.

config

profiles:
  # TINF21CS1 output
  dhbwtinf21cs1:
    source: "http://vorlesungsplan.dhbw-mannheim.de/ical.php?uid=8321001"
    modules:
    - name: "edit-byid"
      id: "[email protected]"
      new-location: "Online"
      new-description: "Link folgt"
      overwrite: "false"

log

time="2022-04-20T11:43:08Z" level=info msg="New Request!" client=141.72.155.39 profile=dhbwtinf21cs1
time="2022-04-20T11:43:08Z" level=debug msg="Requested Module: delete-timeframe"
time="2022-04-20T11:43:08Z" level=debug msg="No after time given. Using time 0.\n"
time="2022-04-20T11:43:08Z" level=debug msg="Deleting events between 0001-01-01T00:00:00Z and 2022-04-20T11:43:08Z\n"
time="2022-04-20T11:43:08Z" level=debug msg="Excluding event with id [email protected]\n"
time="2022-04-20T11:43:08Z" level=debug msg="Excluding event with id [email protected]\n"
[...]
time="2022-04-20T11:43:08Z" level=debug msg="Requested Module: delete-bysummary-regex"
time="2022-04-20T11:43:08Z" level=debug msg="Unknown component type ignored: *ics.VTimezone\n"
time="2022-04-20T11:43:08Z" level=debug msg="Requested Module: delete-byid"
time="2022-04-20T11:43:08Z" level=debug msg="Excluding event with id [email protected]\n"
time="2022-04-20T11:43:08Z" level=debug msg="Requested Module: delete-byid"
time="2022-04-20T11:43:08Z" level=debug msg="Excluding event with id [email protected]\n"
time="2022-04-20T11:43:08Z" level=debug msg="Requested Module: edit-byid"
time="2022-04-20T11:43:08Z" level=debug msg="Changing event with id [email protected]"
2022/04/20 11:43:08 http: panic serving 172.18.0.13:38352: runtime error: invalid memory address or nil pointer dereference
goroutine 23 [running]:
net/http.(*conn).serve.func1()
        /usr/local/go/src/net/http/server.go:1825 +0xbf
panic({0x7e3ea0, 0xb38320})
        /usr/local/go/src/runtime/panic.go:844 +0x258
main.moduleEditId(0xc00038e210, 0xc000178090?)
        /app/modules.go:349 +0x1160
main.callModule(...)
        /app/modules.go:33
main.profileHandler({0x8f1800?, 0xc0003ffc00?}, 0xc00023a800)
        /app/handlers.go:76 +0xada
net/http.HandlerFunc.ServeHTTP(0xc00023a700?, {0x8f1800?, 0xc0003ffc00?}, 0x0?)
        /usr/local/go/src/net/http/server.go:2084 +0x2f
github.com/gorilla/mux.(*Router).ServeHTTP(0xc0002120c0, {0x8f1800, 0xc0003ffc00}, 0xc00023a600)
        /go/pkg/mod/github.com/gorilla/[email protected]/mux.go:210 +0x1cf
net/http.serverHandler.ServeHTTP({0xc000343e00?}, {0x8f1800, 0xc0003ffc00}, 0xc00023a600)
        /usr/local/go/src/net/http/server.go:2916 +0x43b
net/http.(*conn).serve(0xc000294fa0, {0x8f1ab8, 0xc000179140})
        /usr/local/go/src/net/http/server.go:1966 +0x5d7
created by net/http.(*Server).Serve
        /usr/local/go/src/net/http/server.go:3071 +0x4db
^C

URL-Param settings or filters

• #61
• MS/Google compatibility mode #38

Swagger API definition

[Module] Add RSVP to entries

Public API

Used by #45

• Enable Mail Notifications #34
• List "Public" Calendars JM-Lemmi/ical-relay-frontend#1

Upstream unavailiblity handling

Cache upstream calendars, to ensure uptime (maybe with a proxy?)

Exclude only in custom timeframe

[Monitoring] Notify on repeated failure