From bbb4f407b34782c36ff93fa528e3b9f793987d4a Mon Sep 17 00:00:00 2001
From: Richard Moore <github@ricmoo.com>
Date: Sat, 13 Jun 2020 21:26:50 -0400
Subject: [PATCH] Allow provider.ready to stall until the network is available
 (#882).

---
 packages/logger/src.ts/index.ts               |  1 +
 packages/providers/src.ts/base-provider.ts    | 19 +++++++++++++++----
 .../providers/src.ts/json-rpc-provider.ts     |  5 ++++-
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/packages/logger/src.ts/index.ts b/packages/logger/src.ts/index.ts
index d174494ad..128ce0044 100644
--- a/packages/logger/src.ts/index.ts
+++ b/packages/logger/src.ts/index.ts
@@ -66,6 +66,7 @@ export enum ErrorCode {
     UNSUPPORTED_OPERATION = "UNSUPPORTED_OPERATION",
 
     // Network Error (i.e. Ethereum Network, such as an invalid chain ID)
+    //   - event ("noNetwork" is not re-thrown in provider.ready; otherwise thrown)
     NETWORK_ERROR = "NETWORK_ERROR",
 
     // Some sort of bad response from the server
diff --git a/packages/providers/src.ts/base-provider.ts b/packages/providers/src.ts/base-provider.ts
index b60832930..0af4bef04 100644
--- a/packages/providers/src.ts/base-provider.ts
+++ b/packages/providers/src.ts/base-provider.ts
@@ -255,7 +255,7 @@ export class BaseProvider extends Provider {
             network.catch((error) => { });
 
             // Trigger initial network setting (async)
-            this._ready();
+            this._ready().catch((error) => { });
 
         } else {
             const knownNetwork = getStatic<(network: Networkish) => Network>(new.target, "getNetwork")(network);
@@ -315,7 +315,17 @@ export class BaseProvider extends Provider {
     // For "any", this can change (a "network" event is emitted before
     // any change is refelcted); otherwise this cannot change
     get ready(): Promise<Network> {
-        return this._ready();
+        return poll(() => {
+            return this._ready().then((network) => {
+                return network;
+            }, (error) => {
+                // If the network isn't running yet, we will wait
+                if (error.code === Logger.errors.NETWORK_ERROR && error.event === "noNetwork") {
+                    return undefined;
+                }
+                throw error;
+            });
+        });
     }
 
     // @TODO: Remove this and just create a singleton formatter
@@ -334,7 +344,7 @@ export class BaseProvider extends Provider {
     // Fetches the blockNumber, but will reuse any result that is less
     // than maxAge old or has been requested since the last request
     async _getInternalBlockNumber(maxAge: number): Promise<number> {
-        await this.ready;
+        await this._ready();
 
         const internalBlockNumber = this._internalBlockNumber;
 
@@ -401,6 +411,7 @@ export class BaseProvider extends Provider {
             logger.warn("network block skew detected; skipping block events");
             this.emit("error", logger.makeError("network block skew detected", Logger.errors.NETWORK_ERROR, {
                 blockNumber: blockNumber,
+                event: "blockSkew",
                 previousBlockNumber: this._emitted.block
             }));
             this.emit("block", blockNumber);
@@ -507,7 +518,7 @@ export class BaseProvider extends Provider {
     }
 
     async getNetwork(): Promise<Network> {
-        const network = await this.ready;
+        const network = await this._ready();
 
         // Make sure we are still connected to the same network; this is
         // only an external call for backends which can have the underlying
diff --git a/packages/providers/src.ts/json-rpc-provider.ts b/packages/providers/src.ts/json-rpc-provider.ts
index 9a432c2bd..e11b51ccf 100644
--- a/packages/providers/src.ts/json-rpc-provider.ts
+++ b/packages/providers/src.ts/json-rpc-provider.ts
@@ -280,12 +280,15 @@ export class JsonRpcProvider extends BaseProvider {
             } catch (error) {
                 return logger.throwError("could not detect network", Logger.errors.NETWORK_ERROR, {
                     chainId: chainId,
+                    event: "invalidNetwork",
                     serverError: error
                 });
             }
         }
 
-        return logger.throwError("could not detect network", Logger.errors.NETWORK_ERROR);
+        return logger.throwError("could not detect network", Logger.errors.NETWORK_ERROR, {
+            event: "noNetwork"
+        });
     }
 
     getSigner(addressOrIndex?: string | number): JsonRpcSigner {