From 7314f3584495748eab2ef19a93d3139d51552915 Mon Sep 17 00:00:00 2001
From: Charlotte Van Petegem <charlotte.vanpetegem@ugent.be>
Date: Tue, 21 Jun 2022 22:37:27 +0200
Subject: [PATCH] Retry fetches of resource index a few times with exponential
 backoff (#395)

---
 .../me/vanpetegem/accentor/api/album/Album.kt | 35 ++++++++++---------
 .../vanpetegem/accentor/api/artist/Artist.kt  | 35 ++++++++++---------
 .../api/codecconversion/CodecConversion.kt    | 35 ++++++++++---------
 .../me/vanpetegem/accentor/api/plays/Play.kt  | 35 ++++++++++---------
 .../me/vanpetegem/accentor/api/track/Track.kt | 35 ++++++++++---------
 .../me/vanpetegem/accentor/api/user/User.kt   | 35 ++++++++++---------
 .../me/vanpetegem/accentor/api/util/Util.kt   | 16 +++++++++
 7 files changed, 130 insertions(+), 96 deletions(-)
 create mode 100644 app/src/main/java/me/vanpetegem/accentor/api/util/Util.kt

diff --git a/app/src/main/java/me/vanpetegem/accentor/api/album/Album.kt b/app/src/main/java/me/vanpetegem/accentor/api/album/Album.kt
index c437cfe3..4e455bcc 100644
--- a/app/src/main/java/me/vanpetegem/accentor/api/album/Album.kt
+++ b/app/src/main/java/me/vanpetegem/accentor/api/album/Album.kt
@@ -1,6 +1,7 @@
 package me.vanpetegem.accentor.api.album
 
 import com.github.kittinunf.fuel.httpGet
+import me.vanpetegem.accentor.api.util.retry
 import me.vanpetegem.accentor.data.albums.ApiAlbum
 import me.vanpetegem.accentor.data.authentication.AuthenticationData
 import me.vanpetegem.accentor.util.Result
@@ -10,22 +11,24 @@ fun index(server: String, authenticationData: AuthenticationData): Sequence<Resu
     var page = 1
 
     fun doFetch(): Result<List<ApiAlbum>>? {
-        return "$server/api/albums".httpGet(listOf(Pair("page", page)))
-            .set("Accept", "application/json")
-            .set("X-Secret", authenticationData.secret)
-            .set("X-Device-Id", authenticationData.deviceId)
-            .responseObject<List<ApiAlbum>>().third
-            .fold(
-                { a: List<ApiAlbum> ->
-                    if (a.isEmpty()) {
-                        null
-                    } else {
-                        page++
-                        Result.Success(a)
-                    }
-                },
-                { e: Throwable -> Result.Error(Exception("Error getting albums", e)) }
-            )
+        return retry(5) {
+            "$server/api/albums".httpGet(listOf(Pair("page", page)))
+                .set("Accept", "application/json")
+                .set("X-Secret", authenticationData.secret)
+                .set("X-Device-Id", authenticationData.deviceId)
+                .responseObject<List<ApiAlbum>>().third
+                .fold(
+                    { a: List<ApiAlbum> ->
+                        if (a.isEmpty()) {
+                            null
+                        } else {
+                            page++
+                            Result.Success(a)
+                        }
+                    },
+                    { e: Throwable -> Result.Error(Exception("Error getting albums", e)) }
+                )
+        }
     }
 
     return generateSequence { doFetch() }
diff --git a/app/src/main/java/me/vanpetegem/accentor/api/artist/Artist.kt b/app/src/main/java/me/vanpetegem/accentor/api/artist/Artist.kt
index 10c2545c..05bc9a19 100644
--- a/app/src/main/java/me/vanpetegem/accentor/api/artist/Artist.kt
+++ b/app/src/main/java/me/vanpetegem/accentor/api/artist/Artist.kt
@@ -1,6 +1,7 @@
 package me.vanpetegem.accentor.api.artist
 
 import com.github.kittinunf.fuel.httpGet
+import me.vanpetegem.accentor.api.util.retry
 import me.vanpetegem.accentor.data.artists.ApiArtist
 import me.vanpetegem.accentor.data.authentication.AuthenticationData
 import me.vanpetegem.accentor.util.Result
@@ -10,22 +11,24 @@ fun index(server: String, authenticationData: AuthenticationData): Sequence<Resu
     var page = 1
 
     fun doFetch(): Result<List<ApiArtist>>? {
-        return "$server/api/artists".httpGet(listOf(Pair("page", page)))
-            .set("Accept", "application/json")
-            .set("X-Secret", authenticationData.secret)
-            .set("X-Device-Id", authenticationData.deviceId)
-            .responseObject<List<ApiArtist>>().third
-            .fold(
-                { a: List<ApiArtist> ->
-                    if (a.isEmpty()) {
-                        null
-                    } else {
-                        page++
-                        Result.Success(a)
-                    }
-                },
-                { e: Throwable -> Result.Error(Exception("Error getting artists", e)) }
-            )
+        return retry(5) {
+            "$server/api/artists".httpGet(listOf(Pair("page", page)))
+                .set("Accept", "application/json")
+                .set("X-Secret", authenticationData.secret)
+                .set("X-Device-Id", authenticationData.deviceId)
+                .responseObject<List<ApiArtist>>().third
+                .fold(
+                    { a: List<ApiArtist> ->
+                        if (a.isEmpty()) {
+                            null
+                        } else {
+                            page++
+                            Result.Success(a)
+                        }
+                    },
+                    { e: Throwable -> Result.Error(Exception("Error getting artists", e)) }
+                )
+        }
     }
 
     return generateSequence { doFetch() }
diff --git a/app/src/main/java/me/vanpetegem/accentor/api/codecconversion/CodecConversion.kt b/app/src/main/java/me/vanpetegem/accentor/api/codecconversion/CodecConversion.kt
index 18d89431..7fdd0ff6 100644
--- a/app/src/main/java/me/vanpetegem/accentor/api/codecconversion/CodecConversion.kt
+++ b/app/src/main/java/me/vanpetegem/accentor/api/codecconversion/CodecConversion.kt
@@ -1,6 +1,7 @@
 package me.vanpetegem.accentor.api.codecconversion
 
 import com.github.kittinunf.fuel.httpGet
+import me.vanpetegem.accentor.api.util.retry
 import me.vanpetegem.accentor.data.authentication.AuthenticationData
 import me.vanpetegem.accentor.data.codecconversions.ApiCodecConversion
 import me.vanpetegem.accentor.util.Result
@@ -10,22 +11,24 @@ fun index(server: String, authenticationData: AuthenticationData): Sequence<Resu
     var page = 1
 
     fun doFetch(): Result<List<ApiCodecConversion>>? {
-        return "$server/api/codec_conversions".httpGet(listOf(Pair("page", page)))
-            .set("Accept", "application/json")
-            .set("X-Secret", authenticationData.secret)
-            .set("X-Device-Id", authenticationData.deviceId)
-            .responseObject<List<ApiCodecConversion>>().third
-            .fold(
-                { c: List<ApiCodecConversion> ->
-                    if (c.isEmpty()) {
-                        null
-                    } else {
-                        page++
-                        Result.Success(c)
-                    }
-                },
-                { e: Throwable -> Result.Error(Exception("Error getting codec conversions", e)) }
-            )
+        return retry(5) {
+            "$server/api/codec_conversions".httpGet(listOf(Pair("page", page)))
+                .set("Accept", "application/json")
+                .set("X-Secret", authenticationData.secret)
+                .set("X-Device-Id", authenticationData.deviceId)
+                .responseObject<List<ApiCodecConversion>>().third
+                .fold(
+                    { c: List<ApiCodecConversion> ->
+                        if (c.isEmpty()) {
+                            null
+                        } else {
+                            page++
+                            Result.Success(c)
+                        }
+                    },
+                    { e: Throwable -> Result.Error(Exception("Error getting codec conversions", e)) }
+                )
+        }
     }
 
     return generateSequence { doFetch() }
diff --git a/app/src/main/java/me/vanpetegem/accentor/api/plays/Play.kt b/app/src/main/java/me/vanpetegem/accentor/api/plays/Play.kt
index aa87b2b2..05759214 100644
--- a/app/src/main/java/me/vanpetegem/accentor/api/plays/Play.kt
+++ b/app/src/main/java/me/vanpetegem/accentor/api/plays/Play.kt
@@ -3,6 +3,7 @@ package me.vanpetegem.accentor.api.plays
 import com.github.kittinunf.fuel.httpGet
 import com.github.kittinunf.fuel.httpPost
 import java.time.Instant
+import me.vanpetegem.accentor.api.util.retry
 import me.vanpetegem.accentor.data.authentication.AuthenticationData
 import me.vanpetegem.accentor.data.plays.ApiPlay
 import me.vanpetegem.accentor.util.Result
@@ -29,22 +30,24 @@ fun index(server: String, authenticationData: AuthenticationData): Sequence<Resu
     var page = 1
 
     fun doFetch(): Result<List<ApiPlay>>? {
-        return "$server/api/plays".httpGet(listOf(Pair("page", page)))
-            .set("Accept", "application/json")
-            .set("X-Secret", authenticationData.secret)
-            .set("X-Device-Id", authenticationData.deviceId)
-            .responseObject<List<ApiPlay>>().third
-            .fold(
-                { p: List<ApiPlay> ->
-                    if (p.isEmpty()) {
-                        null
-                    } else {
-                        page++
-                        Result.Success(p)
-                    }
-                },
-                { e: Throwable -> Result.Error(Exception("Error getting plays", e)) }
-            )
+        return retry(5) {
+            "$server/api/plays".httpGet(listOf(Pair("page", page)))
+                .set("Accept", "application/json")
+                .set("X-Secret", authenticationData.secret)
+                .set("X-Device-Id", authenticationData.deviceId)
+                .responseObject<List<ApiPlay>>().third
+                .fold(
+                    { p: List<ApiPlay> ->
+                        if (p.isEmpty()) {
+                            null
+                        } else {
+                            page++
+                            Result.Success(p)
+                        }
+                    },
+                    { e: Throwable -> Result.Error(Exception("Error getting plays", e)) }
+                )
+        }
     }
 
     return generateSequence { doFetch() }
diff --git a/app/src/main/java/me/vanpetegem/accentor/api/track/Track.kt b/app/src/main/java/me/vanpetegem/accentor/api/track/Track.kt
index f20e5da1..a4952575 100644
--- a/app/src/main/java/me/vanpetegem/accentor/api/track/Track.kt
+++ b/app/src/main/java/me/vanpetegem/accentor/api/track/Track.kt
@@ -1,6 +1,7 @@
 package me.vanpetegem.accentor.api.track
 
 import com.github.kittinunf.fuel.httpGet
+import me.vanpetegem.accentor.api.util.retry
 import me.vanpetegem.accentor.data.authentication.AuthenticationData
 import me.vanpetegem.accentor.data.tracks.ApiTrack
 import me.vanpetegem.accentor.util.Result
@@ -10,22 +11,24 @@ fun index(server: String, authenticationData: AuthenticationData): Sequence<Resu
     var page = 1
 
     fun doFetch(): Result<List<ApiTrack>>? {
-        return "$server/api/tracks".httpGet(listOf(Pair("page", page)))
-            .set("Accept", "application/json")
-            .set("X-Secret", authenticationData.secret)
-            .set("X-Device-Id", authenticationData.deviceId)
-            .responseObject<List<ApiTrack>>().third
-            .fold(
-                { a: List<ApiTrack> ->
-                    if (a.isEmpty()) {
-                        null
-                    } else {
-                        page++
-                        Result.Success(a)
-                    }
-                },
-                { e: Throwable -> Result.Error(Exception("Error getting tracks", e)) },
-            )
+        return retry(5) {
+            "$server/api/tracks".httpGet(listOf(Pair("page", page)))
+                .set("Accept", "application/json")
+                .set("X-Secret", authenticationData.secret)
+                .set("X-Device-Id", authenticationData.deviceId)
+                .responseObject<List<ApiTrack>>().third
+                .fold(
+                    { a: List<ApiTrack> ->
+                        if (a.isEmpty()) {
+                            null
+                        } else {
+                            page++
+                            Result.Success(a)
+                        }
+                    },
+                    { e: Throwable -> Result.Error(Exception("Error getting tracks", e)) },
+                )
+        }
     }
 
     return generateSequence { doFetch() }
diff --git a/app/src/main/java/me/vanpetegem/accentor/api/user/User.kt b/app/src/main/java/me/vanpetegem/accentor/api/user/User.kt
index a7016ec6..4c63bd86 100644
--- a/app/src/main/java/me/vanpetegem/accentor/api/user/User.kt
+++ b/app/src/main/java/me/vanpetegem/accentor/api/user/User.kt
@@ -1,6 +1,7 @@
 package me.vanpetegem.accentor.api.user
 
 import com.github.kittinunf.fuel.httpGet
+import me.vanpetegem.accentor.api.util.retry
 import me.vanpetegem.accentor.data.authentication.AuthenticationData
 import me.vanpetegem.accentor.data.users.ApiUser
 import me.vanpetegem.accentor.util.Result
@@ -10,22 +11,24 @@ fun index(server: String, authenticationData: AuthenticationData): Sequence<Resu
     var page = 1
 
     fun doFetch(): Result<List<ApiUser>>? {
-        return "$server/api/users".httpGet(listOf(Pair("page", page)))
-            .set("Accept", "application/json")
-            .set("X-Secret", authenticationData.secret)
-            .set("X-Device-Id", authenticationData.deviceId)
-            .responseObject<List<ApiUser>>().third
-            .fold(
-                { u: List<ApiUser> ->
-                    if (u.isEmpty()) {
-                        null
-                    } else {
-                        page++
-                        Result.Success(u)
-                    }
-                },
-                { e: Throwable -> Result.Error(Exception("Error getting users", e)) }
-            )
+        return retry(5) {
+            "$server/api/users".httpGet(listOf(Pair("page", page)))
+                .set("Accept", "application/json")
+                .set("X-Secret", authenticationData.secret)
+                .set("X-Device-Id", authenticationData.deviceId)
+                .responseObject<List<ApiUser>>().third
+                .fold(
+                    { u: List<ApiUser> ->
+                        if (u.isEmpty()) {
+                            null
+                        } else {
+                            page++
+                            Result.Success(u)
+                        }
+                    },
+                    { e: Throwable -> Result.Error(Exception("Error getting users", e)) }
+                )
+        }
     }
 
     return generateSequence { doFetch() }
diff --git a/app/src/main/java/me/vanpetegem/accentor/api/util/Util.kt b/app/src/main/java/me/vanpetegem/accentor/api/util/Util.kt
new file mode 100644
index 00000000..0cfb57da
--- /dev/null
+++ b/app/src/main/java/me/vanpetegem/accentor/api/util/Util.kt
@@ -0,0 +1,16 @@
+package me.vanpetegem.accentor.api.util
+
+import me.vanpetegem.accentor.util.Result
+
+fun <T> retry(n: Int, block: () -> Result<T>?): Result<T>? {
+    var tries = 0
+    var result: Result<T>?
+    do {
+        if (tries > 0) {
+            Thread.sleep((2 shl tries) * 1000L)
+        }
+        result = block()
+        tries++
+    } while (tries < n && result is Result.Error)
+    return result
+}