NTV-530: ApiOperator.java crash (#1608)

app/src/main/java/com/kickstarter/libs/rx/operators/ApiErrorOperator.java

@@ -5,7 +5,6 @@
 import com.kickstarter.services.ResponseException;
 import com.kickstarter.services.apiresponses.ErrorEnvelope;
 
-import java.io.IOException;
 
 import androidx.annotation.NonNull;
 import retrofit2.Response;
@@ -53,13 +52,25 @@ public void onNext(final @NonNull retrofit2.Response<T> response) {
           return;
         }
 
+        if (response == null) {
+          subscriber.onError(new ResponseException(response));
+          return;
+        }
+
         if (!response.isSuccessful()) {
-          try {
-            final ErrorEnvelope envelope = gson.fromJson(response.errorBody().string(), ErrorEnvelope.class);
-            subscriber.onError(new ApiException(envelope, response));
-          } catch (final @NonNull IOException e) {
-            subscriber.onError(new ResponseException(response));
-          }
+            ErrorEnvelope envelope;
+            try {
+              envelope = gson.fromJson(response.errorBody().string(), ErrorEnvelope.class);
+            } catch (final @NonNull Exception e) {
+              envelope = null;
+            }
+
+            if (envelope != null) {
+              subscriber.onError(new ApiException(envelope, response));
+            } else {
+              subscriber.onError(new ResponseException(response));
+            }
+
         } else { 
           subscriber.onNext(response.body());
           subscriber.onCompleted();

app/src/main/java/com/kickstarter/services/apiresponses/ErrorEnvelope.kt

@@ -0,0 +1,166 @@
+package com.kickstarter.services.apiresponses
+
+import android.os.Parcelable
+import androidx.annotation.StringDef
+import com.kickstarter.services.ApiException
+import kotlinx.parcelize.Parcelize
+import java.lang.annotation.Retention
+import java.lang.annotation.RetentionPolicy
+
+@Parcelize
+class ErrorEnvelope private constructor(
+    private val errorMessages: List<String>? = null,
+    private val httpCode: Int = 0,
+    private val ksrCode: String? = null,
+    private val facebookUser: FacebookUser? = null
+) : Parcelable {
+    fun errorMessages() = this.errorMessages
+    fun httpCode() = this.httpCode
+    fun ksrCode() = this.ksrCode
+    fun facebookUser() = this.facebookUser
+
+    @Parcelize
+    class FacebookUser private constructor(
+        private val id: Long = 0L,
+        private val name: String? = null,
+        private val email: String? = null
+    ) : Parcelable {
+        fun id() = this.id
+        fun name() = this.name
+        fun email() = this.email
+
+        @Parcelize
+        data class Builder(
+            private var id: Long = 0L,
+            private var name: String? = null,
+            private var email: String? = null
+        ) : Parcelable {
+            fun id(id: Long?) = apply { this.id = id ?: 0L }
+            fun name(name: String?) = apply { this.name = name }
+            fun email(email: String?) = apply { this.email = email }
+            fun build() = FacebookUser(
+                id = id,
+                name = name,
+                email = email
+            )
+        }
+
+        fun toBuilder() = Builder(
+            id = id,
+            name = name,
+            email = email
+        )
+
+        override fun equals(other: Any?): Boolean {
+            var equals = super.equals(other)
+            if (other is FacebookUser) {
+                equals = id() == other.id() &&
+                    name() == other.name() &&
+                    email() == other.email()
+            }
+            return equals
+        }
+
+        companion object {
+            @JvmStatic
+            fun builder(): Builder {
+                return Builder()
+            }
+        }
+    }
+
+    data class Builder(
+        private var errorMessages: List<String>? = null,
+        private var httpCode: Int = 0,
+        private var ksrCode: String? = null,
+        private var facebookUser: FacebookUser? = null
+    ) {
+        fun errorMessages(errorMessages: List<String?>?) = apply { this.errorMessages = errorMessages?.filterNotNull() }
+        fun httpCode(httpCode: Int?) = apply { this.httpCode = httpCode ?: 0 }
+        fun ksrCode(ksrCode: String?) = apply { this.ksrCode = ksrCode }
+        fun facebookUser(facebookUser: FacebookUser?) = apply { this.facebookUser = facebookUser }
+        fun build() = ErrorEnvelope(
+            errorMessages = errorMessages,
+            httpCode = httpCode,
+            ksrCode = ksrCode,
+            facebookUser = facebookUser
+        )
+    }
+
+    fun toBuilder() = Builder(
+        errorMessages = errorMessages,
+        httpCode = httpCode,
+        ksrCode = ksrCode,
+        facebookUser = facebookUser
+    )
+
+    @StringDef(INVALID_XAUTH_LOGIN, TFA_FAILED, TFA_REQUIRED)
+    @Retention(RetentionPolicy.SOURCE)
+    annotation class ErrorCode
+
+    val isConfirmFacebookSignupError: Boolean
+        get() = CONFIRM_FACEBOOK_SIGNUP == ksrCode()
+    val isInvalidLoginError: Boolean
+        get() = INVALID_XAUTH_LOGIN == ksrCode()
+    val isTfaRequiredError: Boolean
+        get() = TFA_REQUIRED == ksrCode()
+    val isTfaFailedError: Boolean
+        get() = TFA_FAILED == ksrCode()
+    val isMissingFacebookEmailError: Boolean
+        get() = MISSING_FACEBOOK_EMAIL == ksrCode()
+    val isFacebookInvalidAccessTokenError: Boolean
+        get() = FACEBOOK_INVALID_ACCESS_TOKEN == ksrCode()
+    val isUnauthorizedError: Boolean
+        get() = UNAUTHORIZED == ksrCode()
+
+    /*
+    When logging in the only two possible errors are INVALID_XAUTH_LOGIN
+    and TFA_REQUIRED, so we consider anything else an unknown error.
+   */
+    val isGenericLoginError: Boolean
+        get() = INVALID_XAUTH_LOGIN != ksrCode() &&
+            TFA_REQUIRED != ksrCode()
+
+    /**
+     * Returns the first error message available, or `null` if there are none.
+     */
+    fun errorMessage(): String? = errorMessages()?.firstOrNull()
+
+    override fun equals(other: Any?): Boolean {
+        var equals = super.equals(other)
+        if (other is ErrorEnvelope) {
+            equals = errorMessages() == other.errorMessages() &&
+                httpCode() == other.httpCode() &&
+                ksrCode() == other.ksrCode() &&
+                facebookUser() == other.facebookUser()
+        }
+        return equals
+    }
+
+    companion object {
+        @JvmStatic
+        fun builder(): Builder {
+            return Builder()
+        }
+
+        const val CONFIRM_FACEBOOK_SIGNUP = "confirm_facebook_signup"
+        const val INVALID_XAUTH_LOGIN = "invalid_xauth_login"
+        const val TFA_FAILED = "tfa_failed"
+        const val TFA_REQUIRED = "tfa_required"
+        const val MISSING_FACEBOOK_EMAIL = "missing_facebook_email"
+        const val FACEBOOK_INVALID_ACCESS_TOKEN = "facebook_invalid_access_token"
+        const val UNAUTHORIZED = "unauthorized"
+
+        /**
+         * Tries to extract an [ErrorEnvelope] from an exception, and if it
+         * can't returns null.
+         */
+        @JvmStatic
+        fun fromThrowable(t: Throwable): ErrorEnvelope? {
+            if (t is ApiException) {
+                return t.errorEnvelope()
+            }
+            return null
+        }
+    }
+}