问题
I'm trying to have a remote config parameter using the new Remote Config feature of Firebase, and I'm having an issue.
Here's my Remote Config console:
I'm doing a fetch and update in my Application's onCreate():
final FirebaseRemoteConfig remoteConfig = FirebaseRemoteConfig.getInstance();
remoteConfig.fetch().addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()) {
remoteConfig.activateFetched();
}
}
});
And here's how I'm reading it:
FirebaseRemoteConfig remoteConfig = FirebaseRemoteConfig.getInstance();
String value = remoteConfig.getString("active_subscriptions");
Value is returning null.
If I call remoteConfig.getInfo().getLastFetchStatus(), it returns LAST_FETCH_STATUS_SUCCESS, so it seems the fetch is going through successfully.
Any idea why my value is blank?
回答1:
Workaround found! See below
I'm running into the "silent completion" thing - I call "fetch" but onComplete, onSuccess, or onFailure listeners never fire. I tried moving it to an activity onCreate, and still nothing happened, and therefore, the config items never get loaded from the server. I've got Developer Mode enabled, and am calling fetch with a cache value of 0.
I was able to (once) put a breakpoint on the line "public void onComplete(@NonNull Task task) {", which got hit, and then I was able to step through and the onComplete fired. I was then unable to reproduce this same result any other way, including doing the same thing (I think) a second time.
Seems like a timing or concurrency issue, but that makes little sense, given this is an asynchronous call.
Workaround
If you fetch from Activity#onResume (or, I presume, Activity#onStart), it works perfectly. Calling fetch from Activity#onCreate or Application#onCreate results in a call that seemingly never gets handled, and in fact, performance of the app degrades noticeably after the fetch begins, so I think there's a looper running or something.*
Workaround #2
If you really want this to run from Application#onCreate (which I do), this seems to work as well:
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
// Run mFirebaseRemoteConfig.fetch(timeout) here, and it works
}
}, 0);
回答2:
You're likely hitting the caching in Remote Config. The way it works is that Config will cache incoming items locally, and return them. So your last (cached) fetch status was probably before the value was defined, and we get a cached blank value.
You can control the cache expiry, but if you fetch too often you risk getting throttled.
Because this is a common development problem though, there is a developer mode that lets you request more rapidly (for small groups of users):
FirebaseRemoteConfigSettings configSettings =
new FirebaseRemoteConfigSettings.Builder()
.setDeveloperModeEnabled(BuildConfig.DEBUG)
.build();
FirebaseRemoteConfig.getInstance().setConfigSettings(configSettings);
When you call fetch you can then pass a short cache expiration time
long cacheExpiration = 3600;
FirebaseRemoteConfig mFirebaseRemoteConfig = FirebaseRemoteConfig.getInstance();
if (mFirebaseRemoteConfig.getInfo().getConfigSettings().isDeveloperModeEnabled()) {
cacheExpiration = 0;
}
mFirebaseRemoteConfig.fetch(cacheExpiration)
.addOnCompleteListener(new OnCompleteListener<Void>() {
// ...
});
That's how its done in the quickstart sample if you want a full reference.
回答3:
Found the problem.
After adding some logging, I found that the fetch job's onComplete() was never being called. I moved the fetch from my Application's onCreate to a fragment's, and now it works properly!
(Ian Barber, this might be something to look into or clarify, as the logs indicated that Firebase was initialized without an issue when it was in the Application, and the fetches were silent failures.)
回答4:
I had the same problem and no workarounds were helpful in my case. The problem was in the testing device. I used emulator without installing Google Mobile Services, because of this the Complete event was not fired. I tried my phone with GMS and everything worked great. Good luck.
回答5:
First thing in such case is check if you have the correct firebase config and you are connected to firebase .If you have android studio 2.2 got to Tools->Firebase->RemoteConfig - Connect to Firebase and see if you get a notification saying connected.Once Connected do the following in your code: mFirebaseRemoteConfig = FirebaseRemoteConfig.getInstance();
/** NOTE: At this point, your app can use in-app default parameter values.To use in-app
* default values,skip the next section. You can deploy your app without setting
* parameter values on the server,and then later set values on the server to
* override the default behavior and appearance of your app.
*/
mFirebaseRemoteConfig.setDefaults(R.xml.remote_config_defaults);
FirebaseRemoteConfigSettings configSettings = new FirebaseRemoteConfigSettings.Builder()
.setDeveloperModeEnabled(true)
.build();
mFirebaseRemoteConfig.setConfigSettings(configSettings);
And then for fetching config do the following long cacheExpiration = 2000; // Can increase this usually 12hrs is what is recommended
/** If in developer mode cacheExpiration is set to 0 so each fetch will retrieve values from
* the server.*/
if (mFirebaseRemoteConfig.getInfo().getConfigSettings().isDeveloperModeEnabled()) {
cacheExpiration = 0;
}
/** cacheExpirationSeconds is set to cacheExpiration here, indicating that any previously
* fetched and cached config would be considered expired because it would have been fetched
* more than cacheExpiration seconds ago. Thus the next fetch would go to the server unless
* throttling is in progress. The default expiration duration is 43200 (12 hours).
*/
mFirebaseRemoteConfig.fetch(cacheExpiration)//TODO Bring this from a config file
.addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()) {
Log.d(TAG, "Firebase Remote config Fetch Succeeded");
// Once the config is successfully fetched it must be activated before newly fetched
// values are returned.
mFirebaseRemoteConfig.activateFetched();
} else {
Log.d(TAG, "Firebase Remote config Fetch failed");
}
showRemoteConfig();
}
});
Run your App and check in logs " Firebase Remote config Fetch Succeeded ". If you see the same your remote configs are loaded and activated.
回答6:
I've used a similar code like @Ian Barber (copy):
FirebaseRemoteConfigSettings configSettings =
new FirebaseRemoteConfigSettings.Builder()
.setDeveloperModeEnabled(BuildConfig.DEBUG)
.build();
FirebaseRemoteConfig.getInstance().setConfigSettings(configSettings);
My problem was the "BuildConfig.DEBUG", it returns false. So it takes the value 1h in cache until it was fetched again!
回答7:
I also encountered this problem. Turns out I hadn't seen the 'Publish' button in the the Firebase console. :facepalm:
回答8:
I had a problem that Firebase Remote Config didn't fire OnCompleteListener with fetch(0), but with fetch() did.
Looking at FirebaseRemoteConfig.fetch() does not trigger OnCompleteListener every time, I found that the first answer was working sometimes even with fetch(0). Then I again set 3600 seconds for interval, as errors continued to appear:
override fun onPostResume() {
super.onPostResume()
// Initialize FirebaseRemoteConfig here.
...
firebaseRemoteConfig.fetch(3600).addOnCompleteListener { task ->
if (task.isSuccessful) {
firebaseRemoteConfig.activateFetched()
//calling function to check if new version is available or not
checkForUpdate(currentVersionCode, firebaseRemoteConfig.getString(VERSION_CODE_KEY))
} else
Toast.makeText(this@MainActivity, "Someting went wrong please try again",
Toast.LENGTH_SHORT).show()
}
}
回答9:
Well in my case, I am able to receive control in addOnCompleteListener for fetch method but I have fetched values firebaseRemoteConfig just after I called firebaseRemoteConfig.activate(), so when I have tried to get the values from firebaseRemoteConfig it returns me previously saved values because firebaseRemoteConfig.activate() runs asynchronously and new values didn't saved before I am getting them from firebaseRemoteConfig, so I have added complete listener for activate() method also, Here:
firebaseRemoteConfig.fetch()
.addOnCompleteListener(activity, OnCompleteListener {
if (it.isSuccessful)
{
Log.d("task","success")
firebaseRemoteConfig.activate().addOnCompleteListener { // here I have added a listener
val base_url=firebaseRemoteConfig.getString("base_url")
Log.d("base url",base_url)
Toast.makeText(activity, "Base url: $base_url",Toast.LENGTH_SHORT).show()
}
}
else
{
Log.d("task","failure")
}
})
回答10:
I work on a big project and the problem was buried in an unexpected place. Long story short: the firebase application id(normally set through google-services.json) was changed through code:
FirebaseOptions.Builder builder = new FirebaseOptions.Builder();
builder.setApplicationId(applicationId);
builder.setApiKey(apiKey);
FirebaseOptions options = builder.build();
FirebaseApp.initializeApp(context, options);
The solution was to remove that code and let firebase use the info from "google-services.json".
来源：https://stackoverflow.com/questions/37311582/firebase-remote-config-cant-read-any-values-but-fetch-is-successful