fs.readFile works, but readFileSync returns empty content
The following block of code leaves the content variable empty:
const file = fs.createWriteStream("/home/pi/rpi-main/descriptor.json");
http.get(url, function (response) {
let content;
response.pipe(file);
content = fs.readFileSync("/home/pi/rpi-main/descriptor.json", { encoding: "utf-8" });
});
However, if I read the file using fs.readFile, the content is what it should be.
Why is this happening with the synchronous call?
node.js fs
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
add a comment |
The following block of code leaves the content variable empty:
const file = fs.createWriteStream("/home/pi/rpi-main/descriptor.json");
http.get(url, function (response) {
let content;
response.pipe(file);
content = fs.readFileSync("/home/pi/rpi-main/descriptor.json", { encoding: "utf-8" });
});
However, if I read the file using fs.readFile, the content is what it should be.
Why is this happening with the synchronous call?
node.js fs
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
1
Where in your code are you usingcontent?
– Kevin B
Nov 21 '18 at 17:58
add a comment |
The following block of code leaves the content variable empty:
const file = fs.createWriteStream("/home/pi/rpi-main/descriptor.json");
http.get(url, function (response) {
let content;
response.pipe(file);
content = fs.readFileSync("/home/pi/rpi-main/descriptor.json", { encoding: "utf-8" });
});
However, if I read the file using fs.readFile, the content is what it should be.
Why is this happening with the synchronous call?
node.js fs
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
The following block of code leaves the content variable empty:
const file = fs.createWriteStream("/home/pi/rpi-main/descriptor.json");
http.get(url, function (response) {
let content;
response.pipe(file);
content = fs.readFileSync("/home/pi/rpi-main/descriptor.json", { encoding: "utf-8" });
});
However, if I read the file using fs.readFile, the content is what it should be.
Why is this happening with the synchronous call?
node.js fs
node.js fs
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
asked Nov 21 '18 at 17:35
Andrei Oniga
3,03383774
3,03383774
1
Where in your code are you usingcontent?
– Kevin B
Nov 21 '18 at 17:58
add a comment |
1
Where in your code are you usingcontent?
– Kevin B
Nov 21 '18 at 17:58
1
1
Where in your code are you using
content?– Kevin B
Nov 21 '18 at 17:58
Where in your code are you using
content?– Kevin B
Nov 21 '18 at 17:58
add a comment |
1 Answer
1
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It's because pipe is an async function, so when you call readFileSync it actually hasn't begun writing anything to the file.
You should read your file in the callback for the finish event of the pipe.
response.pipe(file).on('finish', () => {
content = fs.readFileSync(filename, { encoding: "utf-8" });
});
answered Nov 22 '18 at 8:34
mihai
23.4k73968
add a comment |
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1 Answer
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1 Answer
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active
oldest
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active
oldest
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active
oldest
votes
It's because pipe is an async function, so when you call readFileSync it actually hasn't begun writing anything to the file.
You should read your file in the callback for the finish event of the pipe.
response.pipe(file).on('finish', () => {
content = fs.readFileSync(filename, { encoding: "utf-8" });
});
answered Nov 22 '18 at 8:34
mihai
23.4k73968
add a comment |
It's because pipe is an async function, so when you call readFileSync it actually hasn't begun writing anything to the file.
You should read your file in the callback for the finish event of the pipe.
response.pipe(file).on('finish', () => {
content = fs.readFileSync(filename, { encoding: "utf-8" });
});
answered Nov 22 '18 at 8:34
mihai
23.4k73968
add a comment |
It's because pipe is an async function, so when you call readFileSync it actually hasn't begun writing anything to the file.
You should read your file in the callback for the finish event of the pipe.
response.pipe(file).on('finish', () => {
content = fs.readFileSync(filename, { encoding: "utf-8" });
});
answered Nov 22 '18 at 8:34
mihai
23.4k73968
It's because pipe is an async function, so when you call readFileSync it actually hasn't begun writing anything to the file.
You should read your file in the callback for the finish event of the pipe.
response.pipe(file).on('finish', () => {
content = fs.readFileSync(filename, { encoding: "utf-8" });
});
answered Nov 22 '18 at 8:34
mihai
23.4k73968
answered Nov 22 '18 at 8:34
mihai
23.4k73968
answered Nov 22 '18 at 8:34
mihai
23.4k73968
answered Nov 22 '18 at 8:34
mihai
23.4k73968
23.4k73968
add a comment |
add a comment |
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1
Where in your code are you using
content?– Kevin B
Nov 21 '18 at 17:58