Myujth

I am trying to call the resource /matchroute via a GET request.
However, I can't figure out how to encode the GPX file so that the resource accepts my request: I always receive HTTP error 400 as a response from the Here server.

As exemplary data I used the following file:

<?xml version="1.0"?>
<gpx version="1.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.topografix.com/GPX/1/0"
xsi:schemaLocation="http://www.topografix.com/GPX/1/0 
http://www.topografix.com/GPX/1/0/gpx.xsd">
 <trk>
 <trkseg>
 <trkpt lat="51.10177" lon="0.39349"/>
 <trkpt lat="51.10181" lon="0.39335"/>
 <trkpt lat="51.10255" lon="0.39366"/>
 <trkpt lat="51.10398" lon="0.39466"/>
 <trkpt lat="51.10501" lon="0.39533"/>
 </trkseg>
 </trk>
</gpx>

that I got from the this example.

I encoded this file using MATLAB's function matlab.net.base64encode which yielded the following base64-encoded string:

PD94bWwgdmVyc2lvbj0iMS4wIj8+PGdweCB2ZXJzaW9uPSIxLjAieG1sbnM6eHNpPSJodHRwOi8vd3d3LnczLm9yZy8y
MDAxL1hNTFNjaGVtYS1pbnN0YW5jZSJ4bWxucz0iaHR0cDovL3d3dy50b3BvZ3JhZml4LmNvbS9HUFgvMS8wInhzaTpz
Y2hlbWFMb2NhdGlvbj0iaHR0cDovL3d3dy50b3BvZ3JhZml4LmNvbS9HUFgvMS8wIGh0dHA6Ly93d3cudG9wb2dyYWZp
eC5jb20vR1BYLzEvMC9ncHgueHNkIj48dHJrPjx0cmtzZWc+PHRya3B0IGxhdD0iNTEuMTAxNzciIGxvbj0iMC4zOTM0
OSIvPjx0cmtwdCBsYXQ9IjUxLjEwMTgxIiBsb249IjAuMzkzMzUiLz48dHJrcHQgbGF0PSI1MS4xMDI1NSIgbG9uPSIw
LjM5MzY2Ii8+PHRya3B0IGxhdD0iNTEuMTAzOTgiIGxvbj0iMC4zOTQ2NiIvPjx0cmtwdCBsYXQ9IjUxLjEwNTAxIiBs
b249IjAuMzk1MzMiLz48L3Rya3NlZz48L3Ryaz48L2dweD4=

However, as stated before, the HERE server consistently responds with HTTP-error 400 to my request

https://rme.api.here.com/2/matchroute.json?app_id=app_id&app_code=app_code&routemode=car&file=...

where "..." equals the above mentioned base64-encoded string.

Question: Could anyone please provide a code sample showing how to encode the above mentioned GPX file correctly (ideally in MATLAB language) so that the /matchroute resource is able to respond?

Remarks:

If I use the base64 string

UEsDBBQAAAAIANmztEQSwaeZzwAAAM8BAAAQAAAAc2FtcGxlLXRyYWNlLmdweIXPTQuCMBwG8HufQnZv%2F605S0k9dj
EIungdZjpSJ27kPn6%2BRBgYXcYYv2cPzzG2deU8805L1YSIYoLiaHMsWvv9uBlYowOrZYhKY9oAoO973DOsugJ2hFBI
z8k1K%2FNabGWjjWiy%2FJ36ShjVqqITd2lxpmo4XVKgMP6vZaCneKIyYabivzHnr4BhCbb6hoZRpnvMp86L%2BdIapx
ImRJxiSuh%2Bj5xq7CWY%2Bcz1EaypA10qxlfVjvOl8rxVxfzDQrk%2FFCfLRs7YpOCzA%2BZd49LoBVBLAQIUABQAAA
AIANmztEQSwaeZzwAAAM8BAAAQAAAAAAAAAAEAIAAAAAAAAABzYW1wbGUtdHJhY2UuZ3B4UEsFBgAAAAABAAEAPgAAAP
0AAAAAAA%3D%3D

from this example the GET request works. However, I couldn't figure out how to reproduce this encoding myself so that I am able to encode my own data accordingly.

Link to the Here API definition: https://developer.here.com/documentation/route-match/topics/resource-matchroute-request.html

Looking at the two base64 strings I can tell you the fundamental difference between them - the first one (which doesn't work) is unescaped whereas the second one (which works) is.

You can convert between the two formats manually using various online tools like this one. The escaped version of the non-working base64 string, in case you want to test it, is:

PD94bWwgdmVyc2lvbj0iMS4wIj8+PGdweCB2ZXJzaW9uPSIxLjAieG1sbnM6eHNpPSJodHRwOi8vd3d3LnczLm9yZy8y
%0AMDAxL1hNTFNjaGVtYS1pbnN0YW5jZSJ4bWxucz0iaHR0cDovL3d3dy50b3BvZ3JhZml4LmNvbS9HUFgvMS8wInhza
Tpz%0AY2hlbWFMb2NhdGlvbj0iaHR0cDovL3d3dy50b3BvZ3JhZml4LmNvbS9HUFgvMS8wIGh0dHA6Ly93d3cudG9wb2
dyYWZp%0AeC5jb20vR1BYLzEvMC9ncHgueHNkIj48dHJrPjx0cmtzZWc+PHRya3B0IGxhdD0iNTEuMTAxNzciIGxvbj0
iMC4zOTM0%0AOSIvPjx0cmtwdCBsYXQ9IjUxLjEwMTgxIiBsb249IjAuMzkzMzUiLz48dHJrcHQgbGF0PSI1MS4xMDI1
NSIgbG9uPSIw%0ALjM5MzY2Ii8+PHRya3B0IGxhdD0iNTEuMTAzOTgiIGxvbj0iMC4zOTQ2NiIvPjx0cmtwdCBsYXQ9I
jUxLjEwNTAxIiBs%0Ab249IjAuMzk1MzMiLz48L3Rya3NlZz48L3Ryaz48L2dweD4%3D

I'm not an expert on this, but as I understand, you need to URL-encode strings only when you want to paste them as-is into the web path of your browser (read about "URL Params"). If you construct your HTTP requests the right way™ (by this I mean specify the headers of the request and the key-value pairs correctly), you shouldn't have to worry about URL-encoding at all, since the tool that you're using (in this case, MATLAB) should take care of the conversion for you.

Unfortunately, I cannot test this theory, as I have no access to the discussed API - but I am fairly certain that this would solve your problem.