Refactor processRow method to handle columns filtering and improve error handling

src/models/file.js

@@ -134,40 +134,42 @@ class File {
     const columnsIndex = {};
     for (let column of columns) {
       columnsIndex[column] = {
-        index: -1,
+        exist: false,
         main: (String(column)).split('.')[0],
         value: column,
+        rest: (String(column)).split('.').slice(1).join('.'),
         last: (String(column)).split('.').pop(),
       };
     }
 
-    let i = 0;
+    const columnsFiltered = [];
+
+    let count = 1;
     fs.createReadStream(this.filepath)
     .pipe(csvParser({ separator: ';' }))
     .on('headers', (headers) => {
+      headers = headers.map(header => typeof header === 'string' ? header.trim() : header);
+      
+      const result = [];
+      for (let key in columnsIndex) {
+        columnsIndex[key].exist = headers.includes(columnsIndex[key].main);
+        if ( columnsIndex[key].exist ) {
+          columnsFiltered.push(columnsIndex[key].value);
+          result.push(columnsIndex[key].last);
+        }
+      }
+      
       // Emit a parse.start event with the url and filepath
-      emitter.emit('parse.start', { url: this.url, filepath: this.filepath, headers });
+      emitter.emit('parse.start', { url: this.url, filepath: this.filepath, headers, result: result });
+
+      stream.write(result.join(';') + "\n");
     })
     .on('data', (row) => {
       // Emit a parse.data event with the url, filepath and data
-      emitter.emit('parse.data', { url: this.url, filepath: this.filepath, data: row, index: i });
-
-      let result = [];
-      if ( i === 0 ) {
-        for(let i = 0; i < row.length; i++) {
-          for (let key of columnsIndex) {
-            if (row[i] === columnsIndex[key].main) {
-              columnsIndex[key].index = i;
-              result.push(columnsIndex[key].last);
-            }
-          }
-        }
-      } else {
-        // Loop through indexes and push the value of the column to result
-        result = this.processRow(row, columnsIndex);
-      }
-      stream.write(result.join(';'));
-      i++;
+      let result = this.processRow(row, columnsIndex, columnsFiltered);
+      emitter.emit('parse.data', { url: this.url, filepath: this.filepath, data: row, result, index: count });
+      stream.write(result.join(';') + "\n");
+      count++;
     })
     .on('error', (err) => {
       // Emit a parse.error event with the error
@@ -175,7 +177,7 @@ class File {
     })
     .on('end', () => {
       // Emit a parse.end event with the url and filepath
-      emitter.emit('parse.end', { url: this.url, filepath: this.filepath, count: i });
+      emitter.emit('parse.end', { url: this.url, filepath: this.filepath, count: count - 1 });
       stream.end();
     });
 
@@ -190,6 +192,10 @@ class File {
    * @return string
    */
   getValueByPath(obj, path) {
+    if ( !path || typeof path !== 'string' ) {
+      return obj;
+    }
+
     const parts = path.split('.');
     let result = obj;
     for (let part of parts) {
@@ -208,37 +214,39 @@ class File {
   /**
    * Generate exported row
    * 
-   * @param array row
+   * @param object row
    * @param object columnsIndex
    * @return array
    */
-  processRow(row, columnsIndex) {
+  processRow(row, columnsIndex, columnsFiltered) {
     const result = [];
 
-    for (let i = 0; i < row.length; i++) {
+    for (let key in row) {
       try {
-        row[i] = JSON.parse(row[i]);
+        if ( typeof row[key] === 'string' && row[key].startsWith('{') && row[key].endsWith('}') ) {
+          row[key] = JSON.parse(row[key]);
+        }
+        
+        row[key.trim()] = row[key]
       } catch (err) {
         // result.push('');
-        console.log(err);
+        console.log(err.message);
       }
     }
 
-    const validIndexes = Object.keys(columnsIndex).filter(key => columnsIndex[key].index !== -1);
-
-    for (let i=0; i < row.length; i++) {
-      if (!validIndexes.includes(i)) {
+    for (let key of columnsFiltered) {
+      if (!columnsIndex[key].exist) {
         continue;
       }
 
-      const column = columnsIndex[i];
-      const item = row[i];
+      const column = columnsIndex[key];
+      const item = row[column.main] || '';
 
       if ( column.primary === column.value ) {
         result.push(item);
       } else {
         if ( typeof item === 'object' ) {
-          result.push(this.getValueByPath(item, column.value));
+          result.push(this.getValueByPath(item, column.rest));
         } else {
           result.push(item);
         }