Handle errors in print requests

README.md

@@ -86,7 +86,7 @@ curl --location 'http://127.0.0.1:1903/printers/PM-241-BT%20(Network)/print' \
 --form 'copies="1"'
 ```
 
-#### Response:
+#### Successful Response:
 
 > On windows the response does not return any real job id. Instead, it returns a 0.
 
@@ -97,3 +97,22 @@ curl --location 'http://127.0.0.1:1903/printers/PM-241-BT%20(Network)/print' \
   ]
 }
 ```
+
+#### Error Responses:
+
+If the request is not successful, the response will contain an error message and an error id.
+
+```json
+{
+  "error": "Missing PDF file",
+  "error_id": "missing_pdf"
+}
+```
+
+Here is a list of possible error ids (but not all of them are implemented yet):
+
+| Error ID      | Description                   |
+|---------------|-------------------------------|
+| missing_pdf   | Missing PDF file              |
+| invalid_label | Invalid label format          |
+| null          | Unsuccessful print job: {...} |

index.js

@@ -19,7 +19,9 @@ app.get('/', (req, res) => {
 })
 
 app.get('/printers', async (req, res) => {
+    try {
         const printers = await getPrinters()
+
         return res.json(printers.map(printer => {
             return {
                 default: false,
@@ -28,6 +30,10 @@ app.get('/printers', async (req, res) => {
                 name: printer.printer || printer.name,
             }
         }))
+    } catch (e) {
+        console.error('Error getting printers', e)
+        return res.json([])
+    }
 })
 
 app.post('/printers/:printer/print', upload.single('file'), async (req, res) => {
@@ -36,6 +42,7 @@ app.post('/printers/:printer/print', upload.single('file'), async (req, res) =>
     // query: user-id: string, docType: label
     // form data: file: binary, copies: string, shipment-ids: string
 
+    try {
         const fileToPrint = req.file.path
         const printJob = await print(fileToPrint, printer)
         const jobId = getRequestId(printJob)
@@ -43,7 +50,13 @@ app.post('/printers/:printer/print', upload.single('file'), async (req, res) =>
         return res.json({
             jobs: [jobId],
         })
-
+    } catch (e) {
+        console.error('Error printing', e)
+        return res.status(400).json({
+            error: 'Unsuccessful print job: ' + e.message,
+            error_id: null,
+        })
+    }
 })
 
 app.listen(port, () => {