feat(server): api endpoint to get Plaid link token

packages/server/src/lib/Plaid/Plaid.ts

@@ -0,0 +1,103 @@
+import { forEach } from 'lodash';
+import { Configuration, PlaidApi, PlaidEnvironments } from 'plaid';
+import { createPlaidApiEvent } from './PlaidApiEventsDBSync';
+import config from '@/config';
+
+const OPTIONS = { clientApp: 'Plaid-Pattern' };
+
+// We want to log requests to / responses from the Plaid API (via the Plaid client), as this data
+// can be useful for troubleshooting.
+
+/**
+ * Logging function for Plaid client methods that use an access_token as an argument. Associates
+ * the Plaid API event log entry with the item and user the request is for.
+ *
+ * @param {string} clientMethod the name of the Plaid client method called.
+ * @param {Array} clientMethodArgs the arguments passed to the Plaid client method.
+ * @param {Object} response the response from the Plaid client.
+ */
+const defaultLogger = async (clientMethod, clientMethodArgs, response) => {
+  const accessToken = clientMethodArgs[0].access_token;
+  // const { id: itemId, user_id: userId } = await retrieveItemByPlaidAccessToken(
+  //   accessToken
+  // );
+  // await createPlaidApiEvent(1, 1, clientMethod, clientMethodArgs, response);
+
+  console.log(response);
+};
+
+/**
+ * Logging function for Plaid client methods that do not use access_token as an argument. These
+ * Plaid API event log entries will not be associated with an item or user.
+ *
+ * @param {string} clientMethod the name of the Plaid client method called.
+ * @param {Array} clientMethodArgs the arguments passed to the Plaid client method.
+ * @param {Object} response the response from the Plaid client.
+ */
+const noAccessTokenLogger = async (
+  clientMethod,
+  clientMethodArgs,
+  response
+) => {
+  console.log(response);
+
+  // await createPlaidApiEvent(
+  //   undefined,
+  //   undefined,
+  //   clientMethod,
+  //   clientMethodArgs,
+  //   response
+  // );
+};
+
+// Plaid client methods used in this app, mapped to their appropriate logging functions.
+const clientMethodLoggingFns = {
+  accountsGet: defaultLogger,
+  institutionsGet: noAccessTokenLogger,
+  institutionsGetById: noAccessTokenLogger,
+  itemPublicTokenExchange: noAccessTokenLogger,
+  itemRemove: defaultLogger,
+  linkTokenCreate: noAccessTokenLogger,
+  transactionsSync: defaultLogger,
+  sandboxItemResetLogin: defaultLogger,
+};
+// Wrapper for the Plaid client. This allows us to easily log data for all Plaid client requests.
+export class PlaidClientWrapper {
+  constructor() {
+    // Initialize the Plaid client.
+    const configuration = new Configuration({
+      basePath: PlaidEnvironments[config.plaid.env],
+      baseOptions: {
+        headers: {
+          'PLAID-CLIENT-ID': config.plaid.clientId,
+          'PLAID-SECRET':
+            config.plaid.env === 'development'
+              ? config.plaid.secretDevelopment
+              : config.plaid.secretSandbox,
+          'Plaid-Version': '2020-09-14',
+        },
+      },
+    });
+
+    this.client = new PlaidApi(configuration);
+
+    // Wrap the Plaid client methods to add a logging function.
+    forEach(clientMethodLoggingFns, (logFn, method) => {
+      this[method] = this.createWrappedClientMethod(method, logFn);
+    });
+  }
+
+  // Allows us to log API request data for troubleshooting purposes.
+  createWrappedClientMethod(clientMethod, log) {
+    return async (...args) => {
+      try {
+        const res = await this.client[clientMethod](...args);
+        await log(clientMethod, args, res);
+        return res;
+      } catch (err) {
+        await log(clientMethod, args, err?.response?.data);
+        throw err;
+      }
+    };
+  }
+}

packages/server/src/lib/Plaid/PlaidApiEventsDBSync.ts

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+/**
+ * Creates a single Plaid api event log entry.
+ *
+ * @param {string} itemId the item id in the request.
+ * @param {string} userId the user id in the request.
+ * @param {string} plaidMethod the Plaid client method called.
+ * @param {Array} clientMethodArgs the arguments passed to the Plaid client method.
+ * @param {Object} response the Plaid api response object.
+ */
+export const createPlaidApiEvent = async (
+  itemId,
+  userId,
+  plaidMethod,
+  clientMethodArgs,
+  response
+) => {
+  const {
+    error_code: errorCode,
+    error_type: errorType,
+    request_id: requestId,
+  } = response;
+  const query = {
+    text: `
+      INSERT INTO plaid_api_events_table
+        (
+          item_id,
+          user_id,
+          plaid_method,
+          arguments,
+          request_id,
+          error_type,
+          error_code
+        )
+      VALUES
+        ($1, $2, $3, $4, $5, $6, $7);
+    `,
+    values: [
+      itemId,
+      userId,
+      plaidMethod,
+      JSON.stringify(clientMethodArgs),
+      requestId,
+      errorType,
+      errorCode,
+    ],
+  };
+  // await db.query(query);
+};

packages/server/src/lib/Plaid/index.ts

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+export * from './Plaid';