refactor(@embark/transaction-logger): change log storage and read

Changes the way the logs are stored to straight up be logged as an
array and then reads it as such. It also removes the reverse from
the read and puts it in the UI instead since it's the UI that needs
it reversed.

packages/cockpit/ui/src/actions/index.js

@@ -173,7 +173,7 @@ export const processLogs = {
 export const CONTRACT_LOGS = createRequestTypes('CONTRACT_LOGS');
 export const contractLogs = {
   request: () => action(CONTRACT_LOGS[REQUEST]),
-  success: (contractLogs) => action(CONTRACT_LOGS[SUCCESS], {contractLogs}),
+  success: (contractLogs) => action(CONTRACT_LOGS[SUCCESS], {contractLogs: contractLogs ? contractLogs.reverse() : []}),
   failure: (error) => action(CONTRACT_LOGS[FAILURE], {error, name: 'contractLogs'})
 };
 

packages/plugins/transaction-logger/src/index.js

@@ -63,7 +63,9 @@ export default class TransactionLogger {
     this.writeLogFile = async.cargo((tasks, callback) => {
       let appendThis = '';
       tasks.forEach(task => {
-        appendThis += `"${new Date().getTime()}":${JSON.stringify(task, getCircularReplacer())},\n`;
+        // Write each line to a JSON string. The replacer is to avoid circular dependencies
+        // Add a comma at the end to be able to make an array off of it when reading
+        appendThis += `${JSON.stringify(task, getCircularReplacer())},\n`;
       });
       this.fs.appendFile(this.logFile, appendThis, (err) => {
         if (err) {
@@ -250,8 +252,7 @@ export default class TransactionLogger {
       apiRoute,
       (ws, _req) => {
         this.events.on('contracts:log', (log) => {
-          ws.send(JSON.stringify(log), () => {
-          });
+          ws.send(JSON.stringify(log), () => {});
         });
       }
     );
@@ -260,39 +261,37 @@ export default class TransactionLogger {
       'get',
       apiRoute,
       async (req, res) => {
-        res.send(JSON.stringify(await this._getLogs()));
+        res.send(await this._readLogs(true));
       }
     );
   }
 
-  async _getLogs() {
-    const data = await this._readLogs();
-    return Object.values(data).reverse();
-  }
-
   _saveLog(log) {
     this.writeLogFile.push(log);
   }
 
-  async _readLogs() {
+  async _readLogs(asString = false) {
     try {
       await this.fs.ensureFile(this.logFile);
       let data = await this.fs.readFile(this.logFile);
 
       data = data.toString();
 
       if (!data) {
-        return {};
+        return asString ? '[]' : [];
       }
 
-      // remove last comma and add braces around
-      data = `{${data.substring(0, data.length - 2)}}`;
+      // remove last comma and add brackets around to make it an array of object logs
+      data = `[${data.substring(0, data.length - 2)}]`;
+      if (asString) {
+        return data;
+      }
 
       return JSON.parse(data);
     } catch (error) {
       this.logger.error('Error reading contract log file', error.message);
       this.logger.trace(error.trace);
-      return {};
+      return asString ? '[]' : [];
     }
   }
 }