Update comments

README.md

@@ -2,4 +2,29 @@
 
 [![Build Status](https://drone.deadbeef.codes/api/badges/steven/ynab-portfolio-monitor/status.svg)](https://drone.deadbeef.codes/steven/ynab-portfolio-monitor)
 
-Track your securities in YNAB for account types and update your balance automatically.
+Track your securities in YNAB for account types and update your balance automatically.  For each configured account, it will update the balance from your broker in YNAB every 6 hours by creating / editing a transaction named "Capital Gains or Losses".  On days that exchanges are closed, it will not do anything.  The end result is that there will be transaction each day with payee "Capital Gains or Losses" in YNAB for each account you configure, which allows tracking your account balance over time.
+
+### Example docker-compose.yml
+
+The values below are examples only.  You can configure as many account pairings as you want using environment variables in a continuous series starting from 0 as shown below.  Two example accounts are configured ending in _0 and _1 but a third can be added by adding account numbers/ID with _2.
+
+```yaml
+version: '3.8'
+
+services:    
+
+  ynab-portfolio-monitor:
+    image: registry.deadbeef.codes/ynab-portfolio-monitor:latest
+    restart: always
+    environment:
+      - questrade_refresh_token=4dsO6652dS3cxtcctscd3ds4Df2E0
+      - questrade_account_0=51000001 # TFSA
+      - questrade_account_1=51000002 # RRSP
+      - questrade_ynab_account_0=731af51e-cb40-4d4a-8094-8654e59e11fc # TFSA
+      - questrade_ynab_account_1=78e76e45-2fbe-4ab1-84e9-64ba0996d015 # RRSP
+      - ynab_budget_id=76566452-67ff-4642-99d1-47d752216fb3
+      - ynab_secret=98Q_J655F_TAyGnhCCDS4uqRe4R5654DT2d-ZXdssZ
+    volumes:
+      - /data/ynab-portfolio-monitor-data:/data
+
+```

main.go

@@ -71,7 +71,9 @@ func main() {
 		// Questrade authentication needs to be refreshed and persistentData written to disk in case app restarts
 		questradeClient, err = questrade.NewClient(persistentData.QuestradeRefreshToken)
 		if err != nil {
-			log.Fatalf("failed to create questrade client: %v", err)
+			log.Printf("failed to create questrade client: %v", err)
+			time.Sleep(time.Minute * 5) // prevent multiple fast login failures
+			continue
 		}
 
 		persistentData.QuestradeRefreshToken = questradeClient.Credentials.RefreshToken

ynab/transactions.go

@@ -31,7 +31,7 @@ type BaseTransaction struct {
 	Deleted               bool        `json:"deleted,omitempty"`
 }
 
-// Used for single transaction requests / responses
+// Used for single transaction responses
 type Transaction struct {
 	Data struct {
 		TransactionIDs  []string        `json:"transaction_ids,omitempty"`
@@ -40,6 +40,7 @@ type Transaction struct {
 	}
 }
 
+// Used for single transaction requests
 type TransactionRequest struct {
 	Transaction BaseTransaction `json:"transaction,omitempty"`
 }
@@ -104,7 +105,7 @@ func (c *Client) CreateTodayYNABCapitalGainsTransaction(accountID string, amount
 	return nil
 }
 
-// Accepts a YNAB account ID and transaction amount and creates a new YNAB transaction
+// Accepts a YNAB account ID, transaction ID and transaction amount and updates the YNAB transaction with the matching ID
 func (c *Client) UpdateTodayYNABCapitalGainsTransaction(accountID string, transactionID string, amount int) error {
 	transaction := TransactionRequest{}
 	transaction.Transaction.AccountID = accountID