feat: add subgraph client

Author: coreyar

src/queries/TokenConvertersQuery.graphql

@@ -0,0 +1,18 @@
+query TokenConverters {
+  tokenConverters {
+    id
+    converterNetwork {
+      id 
+    }
+    destinationAddress
+    baseAsset
+    configs {
+      id
+      tokenAddressIn
+      tokenAddressOut
+      incentive
+      access
+    }
+    paused
+  }
+}

subgraph-client/.graphclientrc.yml

@@ -0,0 +1,8 @@
+sources:
+  - name: venus-protocol-reserve-chapel
+    handler:
+      graphql:
+        endpoint: https://api.thegraph.com/subgraphs/name/venusprotocol/venus-protocol-reserve-chapel
+
+documents:
+  - '../**/*.graphql'

subgraph-client/index.ts

@@ -0,0 +1,34 @@
+import { DocumentNode } from 'graphql';
+import { Client as UrqlClient, createClient } from 'urql/core';
+
+import {
+  TokenConvertersDocument,
+} from './.graphclient';
+
+class SubgraphClient {
+  urqlClient: UrqlClient;
+
+  constructor(url: string) {
+    this.urqlClient = createClient({
+      url,
+      requestPolicy: 'network-only',
+    });
+  }
+
+  async query(document: DocumentNode, args: Record<string, string>) {
+    const result = await this.urqlClient.query(document, args).toPromise();
+    if (result.error) {
+      console.error(result.error);
+    }
+    return result;
+  }
+
+  async getTokenConverters() {
+    const result = await this.query(TokenConvertersDocument, {});
+    return result;
+  }
+}
+
+export default new SubgraphClient(
+  'https://api.thegraph.com/subgraphs/name/venusprotocol/venus-protocol-reserve-chapel',
+);