Our support team works with Topdesk and our dev team works with Jira. We are setting up communication between both tools. We can already send text, but with the images it's going wrong. I receive a status 200, but in the return i have an empty body.
I only can use json(with freemarker) to build the code.
What is have is:

This returns:
==========================================================================
Step 1 'getListOfAttachments'
[2019-08-30T07:28:27.296180Z] Starting FreeMarker template processing
[2019-08-30T07:28:27.297180200Z] Finished FreeMarker template processing
[2019-08-30T07:28:27.297180200Z] Request: GET https://******/attachments
Request headers: {Authorization=[Basic ******], Content-Type=[application/json]}
[2019-08-30T07:28:28.420971100Z] Response status: 206 Partial Content
Response headers: {Date=[Fri, 30 Aug 2019 07:28:28 GMT], Content-Type=[application/json;charset=utf-8], Content-Length=[4124], Connection=[keep-alive], Set-Cookie=[__cfduid=d7790c127f050694e1bf2256a36837f1b1567150107; expires=Sat, 29-Aug-20 07:28:27 GMT; path=/; domain=.topdesk.net; HttpOnly], Cache-Control=[no-store], CF-Ray=[50e50c4a6a30bf37-AMS], Access-Control-Allow-Origin=[*], Expect-CT=[max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"], Strict-Transport-Security=[max-age=31536000; includeSubDomains; preload], X-Content-Type-Options=[nosniff], X-Robots-Tag=[noindex,nofollow], X-XSS-Protection=[1; mode=block], Vary=[Accept-Encoding], Server=[cloudflare]}
Response body: [{"id":"1d5c37b6-ac05-4048-9f1b-2f3ee2681e9e","fileName":"iectx (8).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/1d5c37b6-ac05-4048-9f1b-2f3ee2681e9e/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-22T13:43:10.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"5b7cd644-8a2b-42ec-b4e3-a9a62e652d3b","fileName":"iectx (7).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/5b7cd644-8a2b-42ec-b4e3-a9a62e652d3b/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-22T12:49:58.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"8c486610-5c83-4d43-aa71-3ae17cedc0f4","fileName":"iectx (6).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/8c486610-5c83-4d43-aa71-3ae17cedc0f4/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-22T08:27:42.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"2622d602-887c-4e3d-8516-88899eda1eef","fileName":"iectx (5).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/2622d602-887c-4e3d-8516-88899eda1eef/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T17:11:13.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"916291bf-bb1b-4367-9a38-d58f58f5dd53","fileName":"iectx (4).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/916291bf-bb1b-4367-9a38-d58f58f5dd53/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T16:31:13.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"20c2d785-a25c-448b-abc1-8c054e8b758d","fileName":"iectx (3).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/20c2d785-a25c-448b-abc1-8c054e8b758d/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T16:28:19.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"b19c0b0e-a8bf-4f04-9709-862859aed9d1","fileName":"iectx (2).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/b19c0b0e-a8bf-4f04-9709-862859aed9d1/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T16:23:59.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"01b9699c-f5f1-4f51-b0df-774f4079bf4a","fileName":"iectx (1).png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/01b9699c-f5f1-4f51-b0df-774f4079bf4a/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T16:10:36.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"280c4b20-6493-4c5e-af65-a329e275e940","fileName":"iectx.png","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/280c4b20-6493-4c5e-af65-a329e275e940/download","size":19654,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T14:56:49.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null},{"id":"918be7a8-3d33-4d8d-aa00-b8f3441561b5","fileName":"8200Uc.PNG","downloadUrl":"/tas/api/incidents/id/f422740b-e0a1-4263-a209-7f0d78a6d8fc/attachments/918be7a8-3d33-4d8d-aa00-b8f3441561b5/download","size":19514,"description":null,"invisibleForCaller":false,"entryDate":"2019-08-20T14:40:50.000+0000","operator":{"id":"c2eba81b-6b9c-45f2-aac9-3e1c5ccc1b0a","name":"Jürgen (ADMIN) Lehoucke"},"person":null}]
[2019-08-30T07:28:28.420971100Z] Storing response data
[2019-08-30T07:28:28.421982300Z] Successfully finished step 'getListOfAttachments'
==========================================================================
Step 2 'downloadFirstAttachment'
[2019-08-30T07:28:28.421982300Z] Starting FreeMarker template processing
[2019-08-30T07:28:28.421982300Z] Finished FreeMarker template processing
[2019-08-30T07:28:28.421982300Z] Request: GET ******/attachments/1d5c37b6-ac05-4048-9f1b-2f3ee2681e9e/download
Request headers: {Authorization=[Basic ******], Content-Type=[application/json]}
[2019-08-30T07:28:28.664058100Z] Response status: 200 OK
Response headers: {Date=[Fri, 30 Aug 2019 07:28:28 GMT], Content-Type=[image/png;charset=utf-8], Content-Length=[19654], Connection=[keep-alive], Set-Cookie=[__cfduid=d39d528a8de105c9e37c8d3ce978fb8791567150108; expires=Sat, 29-Aug-20 07:28:28 GMT; path=/; domain=.topdesk.net; HttpOnly], Cache-Control=[no-store], CF-Ray=[50e50c515aff9c99-AMS], Access-Control-Allow-Origin=[*], Content-Disposition=[attachment; filename="iectx (8).png"; filename*=UTF-8''iectx%20%288%29%2Epng], Expect-CT=[max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"], Strict-Transport-Security=[max-age=31536000; includeSubDomains; preload], X-Content-Type-Options=[nosniff], X-Robots-Tag=[noindex,nofollow], X-XSS-Protection=[1; mode=block], Vary=[Accept-Encoding], Server=[cloudflare]}
Response body: �PNG
IHDRe���+sRGB���gAMA���a ......... (lot more sign's/code but i cut them off in this post)
[2019-08-30T07:28:28.664058100Z] Storing response data
[2019-08-30T07:28:28.664058100Z] Successfully finished step 'downloadFirstAttachment'
==========================================================================
when I post this picture to our topdesk enviroment, it works perfect

When i try to do the same to jira:

I get the following response:
Step 5 'UploadJira2'
[2019-08-30T07:28:30.416467600Z] Starting FreeMarker template processing
[2019-08-30T07:28:30.417467700Z] Finished FreeMarker template processing
[2019-08-30T07:28:30.417467700Z] Request: POST https://******/rest/api/2/issue/HORA-83950/attachments
Request headers: {Authorization=[Basic *****], X-Atlassian-Token=[nocheck], Content-Type=[multipart/form-data; boundary=BOUNDARY]}
Request body: BOUNDARY--
"Content-Type": "image/png";"charset"="utf-8"
Content-Transfer-Encoding: binary
Content-Type: application/octet-stream; "name"="file"; "filename"="iectx (8).png"; "key"="file";
file:"�PNG
IHDR.......(lot more sign's/code but i cut them off in this post)
BOUNDARY--
[2019-08-30T07:28:30.599478700Z] Response status: 200 200
Response headers: {Date=[Fri, 30 Aug 2019 07:28:30 GMT], Server=[Apache], X-AREQUESTID=[568x12315x1], X-XSS-Protection=[1; mode=block], X-Content-Type-Options=[nosniff], X-Frame-Options=[SAMEORIGIN], Content-Security-Policy=[frame-ancestors 'self'], X-ASEN=[SEN-L12537288], X-Seraph-LoginReason=[OK], X-ASESSIONID=[m8ea5g], X-AUSERNAME=[TopdeskConnection], Cache-Control=[no-cache, no-store, no-transform], Content-Type=[application/json;charset=UTF-8], Set-Cookie=[JSESSIONID=A4F6E33DE5FF077CD32C3318906BDCA2; Path=/jira; Secure; HttpOnly, atlassian.xsrf.token=BIMZ-26KK-G8Y7-TJMK_c46de5464bb96f1108f44bd5339878f82c6b4707_lin; Path=/jira; Secure, dtCookie=70452A76B2E1FEF16E0DAB8065E28AE6|SmlyYXwx; Path=/; Domain=.***.be], Keep-Alive=[timeout=5, max=100], Connection=[Keep-Alive], Transfer-Encoding=[chunked], Content-Length=[-1]}
Response body: []
[2019-08-30T07:28:30.599478700Z] Storing response data
[2019-08-30T07:28:30.600479600Z] Successfully finished step 'UploadJira2'
---------------------------------------------------------------------------------------
When i look into the log's of jira, i see there communication, but i can't find the attachment.
Does anybody has an idee to fix this?