Why does the PUT method throw an error when the GET method doesn't?

Question

I have extracted two functions from my app that are similarly constructed and the code block that calls them both. One function is a HTTP GET that returns a file 'keys.json'. The other is a HTTP PUT that sends an empty version of 'keys.json' back to the API.

The GET

const putKeysJson = async () => {
        //  this is the opening put back of an empty keys.json file
        //  putting this file back empty at the start of the run prevents
        //  double processing of JsonData files because there is an empty list of keys
        //  therefore nothing can be selected for processing
        //  @ EOJ, keys.json will be updated with any keys that may have failed to process
        const options = {
            method: 'PUT',
            uri: baseURL + keysID,
            resolveWithFullResponse: true,
            body: {
                keys: []
            },
            json: true // Automatically stringifies the body to JSON
        };
        return (await rpn(options)).body;
};

The PUT

const putKeysJson = async () => {
    //  this is the opening put back of an empty keys.json file
    //  putting this file back empty at the start of the run prevents
    //  double processing of JsonData files because there is an empty list of keys
    //  therefore nothing can be selected for processing
    //  @ EOJ, keys.json will be updated with any keys that may have failed to process
    const options = {
        method: 'PUT',
        uri: baseURL + keysID,
        resolveWithFullResponse: true,
        body: {
            keys: []
        },
        json: true // Automatically stringifies the body to JSON
    };
    return (await rpn(options)).req.Request.body;
};

The calling block:

rtProcess.get('/process', async (req, res) => {
    const jsonKeysList = await (getKeysJson());
    console.log("GET json keys", jsonKeysList);
    try {
        const keys = await (putKeysJson());
        console.log("PUT empty keys", keys);
    } catch(err) {
        console.log('Error',err.statusCode, err.name);
    }

    //
    // other code
    //
    res.render("process");
}); // end of process route

Here is my console output:

GET json keys [ '5sM5YLnnNMN_1540338527220.json',
  '5sM5YLnnNMN_1540389571029.json',
  '6tN6ZMooONO_1540389269289.json' ]
Error 404 StatusCodeError

Showing the GET to be successful and the PUT taking the catch(err) block. And, why a 404.

Answer 1 · 2018-11-21T19:45:11Z

November 21, 2018 7:45pm

I completely revised this API. I forgot to close out this request. Sorry.

Answer 2 · 2018-11-08T16:34:26Z

November 8, 2018 4:34pm

Brendan: This is an API that is my creation for my client.

Kris: You are absolutely correct. I am not only a rookie, I am not very careful either. I copied the PUT function into both examples. Here is the GET function:

const getKeysJson = async () => {
    const options = {
        method: 'GET',
        uri: baseURL + keysID,
        headers: { 'User-Agent': 'Request-Promise' },
        json: true // Automatically parses the JSON string in the response
    };
    return (await rpn(options)).keys;
};

Here is one thing I figured out (one of those AH HAH moments). The baseURL is prefixed by '/static', which as I understand it, is for serving up static files. I have been looking at this for a week thinking 'Yeah, static is what I am dealing with here.' But then, that was when I was only looking at the GET method. The minute I tried to use the PUT method, the file is no longer static, is it! That would explain why the GET worked and the PUT doesn't. A case of going brain-dead and not connecting the dots, how embarrassing.

So, I moved the quizdata folder from public up to the root (so I could maintain the integrity of the express

app.use('/static', express.static(path.join(__dirname, 'public')));

command. I changed the base url to declare the entire path as:

'http://localhost:3000/Users/doug5solas/sandbox/...myclientname.../server/quizdata/'

Instead of using the '/static' shorthand notation.

I think that should take care of the 404 error on the PUT. But now I am getting a 404 on the GET, so maybe not. However, the new error also includes and Unhandled Promise Reject Warning so I probably need to either use a try/catch or a promise resolve. But I am blathering at this point.

Answer 3 · 2018-11-09T00:45:24Z

November 9, 2018 12:45am

Brendan:

Very cogent question. I don't really see how to utilize an express PUT route in this API. There may be one but I don't know how to bind to it. Here is a link to a gist with the entire file in it. You can see the I have put a placeholder PUT route in, at the bottom of the file. But I see no way to bind to that route.

https://gist.github.com/dhawkinson/b40f6936caafe48d7be41551119f9817

I am also including links to two images that graphically show my conception of the API. One is a higher level overview and the other is more of a drill down. I am trying to do something a bit on the unusual side, I agree, but I can't believe there has never been someone that has had to tackle a similar problem with Node/Express in the past.

https://www.dropbox.com/s/ctddgv21pzai4ot/storylineDataCapture.jpg?dl=0

https://www.dropbox.com/s/t2flc7xkx320btq/storylineDataCaptureExplained.jpg?dl=0

If you have some ideas, I am all ears.

I think what you are driving at, is something more like this:

module.exports = (rtProcess) => {
    rtProcess.get('/process', async (req, res) => {

        const jsonKeysList = await (getKeysJson());
        console.log("GET keys.json", jsonKeysList);

        res.render("process");  //  this may need to be somewhere else
    }); // end of get route

    rtProcess.get('/process/failedKeys', async (req, res) => {

        //  code here

    }); // end of get failedKeys route

    rtProcess.get('/process/jsonData', async (req, res) => {

        //  code here
        //  loop on the keys (outcomeID) -- get and parse JSON, then write SQL
        jsonKeysList.forEach(outcomeID => {
            console.log(outcomeID);
            getJsonData(outcomeID);

            parseLearner();
            parseCourse();
            parseOutcome();
            parseOutcomeDetails();

            /*==================================================
                All data has been gathered -- now write it
            ==================================================*/

            log = [];
            writeLearnerSQL();
            writeCourseSQL();
            writeOutcomeSQL();
            writeLogSQL();

        });

    }); // end of jsonData route

    rtProcess.put('/process/emptyKeys', async (req, res) => {

        //  code here
        const keys = await (putKeysJson());
        console.log("PUT empty keys", keys);

    }); // end of emptyKeys route

    rtProcess.put('/process/failedKeys', async (req, res) => {

        //  this routine kicks in if any Outcome transactions fail to commit.
        //  the outcome key if written back the Keys list for reprocessing
        //  after troubleshooting the problems
        //  hopefully this never happens
        if (keysFailed) {
            putKeysFailed(keysFailed);
        }

    }); // end of put failedKeys route
};

But I'm not sure how to pull that off since the only route in this example that is tied to an <a> tag/ href is the very first one.

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Doug Hawkinson

Doug Hawkinson

Why does the PUT method throw an error when the GET method doesn't?

KRIS NIKOLAISEN

KRIS NIKOLAISEN

Brendan Whiting

Brendan Whiting

3 Answers

Doug Hawkinson

Doug Hawkinson

Doug Hawkinson

Doug Hawkinson

Brendan Whiting

Brendan Whiting

Doug Hawkinson

Doug Hawkinson

Brendan Whiting

Brendan Whiting