In the Crashlytics dashboard, you can click into an issue and get a detailed
event report. You can customize those reports to help you better understand
what's happening in your app and the circumstances around events reported to
Crashlytics.
Automatically get
breadcrumb logs
if your app uses the
Firebase SDK for Google Analytics. These logs give you visibility into
user actions leading up to a Crashlytics-collected event in your app.
Turn off automatic crash reporting and
enable opt-in reporting
for your users. Note that, by
default, Crashlytics automatically collects crash reports for all your
app's users.
Add custom keys
Custom keys help you get the specific state of your app leading up to a crash.
You can associate arbitrary key/value pairs with your crash reports, then use
the custom keys to search and filter crash reports in the Firebase console.
- In the
Crashlytics dashboard
, you can search for issues
that match a custom key.
- When you're reviewing a specific issue in the console, you can view the
associated custom keys for each event (
Keys
subtab) and even filter the
events by custom keys (
Filter
menu at the top of the page).
Use the
setCustomValue
method to set key/value pairs. For example:
Swift
// Set int_key to 100.
Crashlytics.crashlytics().setCustomValue(100, forKey: "int_key")
// Set str_key to "hello".
Crashlytics.crashlytics().setCustomValue("hello", forKey: "str_key")
Objective-C
When setting integers, booleans, or floats, box the value as
@(
value
)
.
// Set int_key to 100.
[[FIRCrashlytics crashlytics] setCustomValue:@(100) forKey:@"int_key"];
// Set str_key to "hello".
[[FIRCrashlytics crashlytics] setCustomValue:@"hello" forKey:@"str_key"];
You can also modify the value of an existing key by calling the key and setting
it to a different value. For example:
Swift
Crashlytics.crashlytics().setCustomValue(100, forKey: "int_key")
// Set int_key to 50 from 100.
Crashlytics.crashlytics().setCustomValue(50, forKey: "int_key")
Objective-C
[[FIRCrashlytics crashlytics] setCustomValue:@(100) forKey:@"int_key"];
// Set int_key to 50 from 100.
[[FIRCrashlytics crashlytics] setCustomValue:@(50) forKey:@"int_key"];
Add key/value pairs in bulk by using the
setCustomKeysAndValues
method with an
NSDictionary as the only parameter:
Swift
let keysAndValues = [
"string key" : "string value",
"string key 2" : "string value 2",
"boolean key" : true,
"boolean key 2" : false,
"float key" : 1.01,
"float key 2" : 2.02
] as [String : Any]
Crashlytics.crashlytics().setCustomKeysAndValues(keysAndValues)
Objective-C
NSDictionary *keysAndValues =
@{@"string key" : @"string value",
@"string key 2" : @"string value 2",
@"boolean key" : @(YES),
@"boolean key 2" : @(NO),
@"float key" : @(1.01),
@"float key 2" : @(2.02)};
[[FIRCrashlytics crashlytics] setCustomKeysAndValues: keysAndValues];
Add custom log messages
To give yourself more context for the events leading up to a crash, you can add
custom Crashlytics logs to your app. Crashlytics associates the logs
with your crash data and displays them in the Crashlytics page of the
Firebase console
, under the
Logs
tab.
Swift
Use
log()
or
log(format:, arguments:)
to help pinpoint issues. If you
want to get a useful log output with messages, the object that you pass to
log()
must conform to the
CustomStringConvertible
property.
log()
returns the description property you define for
the object. For example:
Crashlytics.crashlytics().log("Higgs-Boson detected! Bailing out…, \(
attributesDict
)")
.log(format:, arguments:)
formats values returned from calling
getVaList()
. For example:
Crashlytics.crashlytics().log(format: "%@, %@", arguments: getVaList(["Higgs-Boson detected! Bailing out…",
attributesDict
]))
For more details on how to use
log()
or
log(format:, arguments:)
,
refer to the Crashlytics
reference documentation
.
Objective-C
Use
log
or
logWithFormat
to help pinpoint issues. Note that if you
want to get a useful log output with messages, the object that you pass
to either method must override the
description
instance property.
For example:
[[FIRCrashlytics crashlytics] log:@"Simple string message"];
[[FIRCrashlytics crashlytics] logWithFormat:@"Higgs-Boson detected! Bailing out... %@",
attributesDict
];
[[FIRCrashlytics crashlytics] logWithFormat:@"Logging a variable argument list %@" arguments:
va_list_arg
];
For more details on how to use
log
and
logWithFormat
, refer to the
Crashlytics
reference documentation
.
Set user identifiers
To diagnose an issue, it’s often helpful to know which of your users experienced
a given crash. Crashlytics includes a way to anonymously identify users in
your crash reports.
To add user IDs to your reports, assign each user a unique identifier in the
form of an ID number, token, or hashed value:
Swift
Crashlytics.crashlytics().setUserID("123456789")
Objective-C
[[FIRCrashlytics crashlytics] setUserID:@"123456789"];
If you ever need to clear a user identifier after you set it, reset the value to
a blank string. Clearing a user identifier does not remove existing
Crashlytics records. If you need to delete records associated with a user
ID,
contact Firebase support
.
Get breadcrumb logs
Breadcrumb logs give you a better understanding of the interactions that a user
had with your app leading up to a crash, non-fatal, or ANR event. These logs can
be helpful when trying to reproduce and debug an issue.
Breadcrumb logs are powered by Google Analytics, so to get breadcrumb logs, you
need to
enable Google Analytics
for your Firebase project and
add the Firebase SDK for Google Analytics
to your app. Once these requirements are met, breadcrumb logs are automatically
included with an event's data within the
Logs
tab when you view the details
of an issue.
The Analytics SDK
automatically logs the
screen_view
event
which enables the breadcrumb logs to show a list of screens viewed before the
crash, non-fatal, or ANR event. A
screen_view
breadcrumb log contains a
firebase_screen_class
parameter.
Breadcrumb logs are also populated with any
custom events
that you manually log within the user’s
session, including the event's parameter data. This data can help show a series
of user actions leading up to a crash, non-fatal, or ANR event.
Note that you can
control the collection and use of Google Analytics data
,
which includes the data that populates breadcrumb logs.
Enable opt-in reporting
By default, Crashlytics automatically collects crash reports for all your
app's users. To give users more control over the data they send, you can enable
opt-in reporting by disabling automatic reporting and only sending data to
Crashlytics when you choose to in your code:
Turn off automatic collection by adding a new key to your
Info.plist
file:
- Key:
FirebaseCrashlyticsCollectionEnabled
- Value:
false
Enable collection for select users by calling the Crashlytics data
collection override at runtime. The override value persists across
launches of your app so Crashlytics can automatically collect reports.
To opt out of automatic crash reporting, pass
false
as the override value.
When set to
false
, the new value does not apply until the next run of the
app.
Swift
Crashlytics.crashlytics().setCrashlyticsCollectionEnabled(true)
Objective-C
[[FIRCrashlytics crashlytics] setCrashlyticsCollectionEnabled:YES];
Manage Crash Insights data
Crash Insights helps you resolve issues by comparing your anonymized stack
traces to traces from other Firebase apps and letting you know if your issue is
part of a larger trend. For many issues, Crash Insights even provides resources
to help you debug the crash.
Crash Insights uses aggregated crash data to identify common stability trends.
If you’d prefer not to share your app's data, you can opt-out of Crash Insights
from the
Crash Insights
menu at the top of your Crashlytics issue list
in the
Firebase console
.