https://github.com/roblabs/mapview-log-extensions
Opinionated logging of `mapView` events for MapKit, Mapbox & MapLibre. Measure in Xcode console or Xcode Instruments.
https://github.com/roblabs/mapview-log-extensions
docc mapbox mapkit maplibre swift xcode-instruments
Last synced: 2 months ago
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Opinionated logging of `mapView` events for MapKit, Mapbox & MapLibre. Measure in Xcode console or Xcode Instruments.
- Host: GitHub
- URL: https://github.com/roblabs/mapview-log-extensions
- Owner: roblabs
- License: mit
- Created: 2021-06-15T00:57:37.000Z (almost 4 years ago)
- Default Branch: main
- Last Pushed: 2022-01-30T00:01:34.000Z (about 3 years ago)
- Last Synced: 2025-02-14T06:14:59.235Z (3 months ago)
- Topics: docc, mapbox, mapkit, maplibre, swift, xcode-instruments
- Language: Swift
- Homepage:
- Size: 3.71 MB
- Stars: 2
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# ``MapViewOSLogExtensions``
Opinionated Swift logging of map view events for [MapKit](https://developer.apple.com/documentation/mapkit/mkmapviewdelegate), [Mapbox](https://docs.mapbox.com/ios/maps/api/6.3.0/Protocols/MGLMapViewDelegate.html) & [MapLibre](https://github.com/maplibre/maplibre-gl-native/blob/master/platform/ios/platform/macos/src/MGLMapViewDelegate.h). Plays well with Xcode Instruments for millisecond timing of events.
## Overview
Measure map view events such as `DidFinishLoadingStyle`, `DidFinishRenderingMap`, & `DidBecomeIdle` using `OSLog` and `os.signpost`.
## Topics
### How to Use
#### 1. Add the package via the Swift Package Manager.
#### 2. Add Opinionated Logs for map view.
See the enumeration ``mapEvents`` for suggested strings for your logs.
```swift
import OSLog
import MapViewOSLogExtensions
func beginMeasurementInterval() {
// Construct the map view object
OSLog.mapView(.begin, "measure some event")
}
func setZoomLevel(_ zoomLevel: Double) {
// Logs to Xcode console & Xcode Instruments
OSLog.mapView(.event, "zoomLevel: \(zoomLevel)")
mapView.zoomLevel = zoomLevel
}
func endMeasurementInterval() {
// This could be in an event handlers
OSLog.mapView(.end, "measure some event")
}
```
---
## Xcode Instruments
Use Xcode Instruments for filtering logs and measuring event intervals. For more information on Xcode Instruments & signposts, see [Measuring Performance Using Logging](https://developer.apple.com/videos/play/wwdc2018/405/) from WWDC 2018.
*Xcode Instruments with the Logging template selected.*
---
## Filter Logs 🦮
If you use the opinionated log strings, such as `OSLog.mapEvents.DidFinishLoadingMap`, then you filter the Instruments data by using the filter `mapview`. Through empirical testing, for Mapbox flavored SDKs the log analysis shows that map view events occur in this order, with `DidFinishLoadingMap` likely the event of when the map is displayed for the user.
```console
00:00.286.828 [com.roblabs.log-mapview] Coordinator init, init(_:), line: 54
00:00.288.457 [com.roblabs.log-mapview] 🦮100. WillStartLoadingMap, mapViewWillStartLoadingMap(_:), line: 59
00:00.292.670 [com.roblabs.log-mapview] 🦮1. WillStartRenderingMap, mapViewWillStartRenderingMap(_:), line: 63
00:00.321.970 [com.roblabs.log-mapview] 🦮2. DidFinishLoadingStyle, mapView(_:didFinishLoading:), line: 67
00:00.531.795 [com.roblabs.log-mapview] 🦮3. DidFinishRenderingMap, mapViewDidFinishRenderingMap(_:fullyRendered:), line: 71
00:00.531.982 [com.roblabs.log-mapview] 🦮4. DidFinishLoadingMap, mapViewDidFinishLoadingMap(_:), line: 75
00:01.129.784 [com.roblabs.log-mapview] 🦮5. DidBecomeIdle, mapViewDidBecomeIdle(_:), line: 79
```
---
## Results 📈
Sample data from five runs of [Geography Class](https://github.com/roblabs/openmaptiles-ios-demo) on a Simulator. This sample project is making use of the `OSLog` extensions for map views.
| Event `DidFinishLoadingMap` (msec)
| :-------------
| 531
| 499
| 500
| 529
| 514
| **mean = 514**
### Log vs. Signpost
*Logging template with `os_log` and set input filter by a string.*
> Making observations on the data, the first entry is for 381 milliseconds, and the first entry for `DidBecomeIdle` is at 1258 milliseconds. The event `DidFinishLoadingMap` was at 651 milliseconds. Screen recording of the simulator or device can be useful to show when the map is shown to the customer.
---
*Logging template with `os_signpost` and input filter set to filter by the name of the subsystem.*
> This view of the `os_signpost` shows that the first entry is for `DidBecomeIdle` is at 1258 milliseconds. The event `DidFinishLoadingMap` was at 651 milliseconds. Screen recording of the simulator or device can be useful to show when the map is shown to the customer. The event `WillStartLoadingMap` started at 401 milliseconds, or about 850 milliseconds. There is also a second `DidBecomeIdle` event occuring several seconds later.
