curl로 호출할 때 발생하는 오류 정리
Azure Cognitive 서비스를 curl로 호출할 때 다음과 같이 오류가 발생하는 경우가 있습니다.
C:\> curl -g -v POST "https://eastasia.api.cognitive.microsoft.com/vision/v1.0/analyze?visualFeatures=Categories" -H "Content-Type: application/json" -H "Ocp-Apim-Subscription-Key: ffcd240d42fa4fe98bf0286120fb2801" --data-ascii '{"url": "http://sysnet.blob.core.windows.net/sysnetimages/trip_to_jp_4.png"}'
* Rebuilt URL to: POST/
* Could not resolve host: POST
* Closing connection 0
curl: (6) Could not resolve host: POST
* Trying 13.94.26.39...
* Connected to eastasia.api.cognitive.microsoft.com (13.94.26.39) port 443 (#1)
* schannel: SSL/TLS connection with eastasia.api.cognitive.microsoft.com port 443 (step 1/3)
* schannel: checking server certificate revocation
* schannel: ALPN, offering http/1.1
* schannel: sending initial handshake data: sending 216 bytes...
* schannel: sent initial handshake data: sent 216 bytes
* schannel: SSL/TLS connection with eastasia.api.cognitive.microsoft.com port 443 (step 2/3)
* schannel: failed to receive handshake, need more data
* schannel: SSL/TLS connection with eastasia.api.cognitive.microsoft.com port 443 (step 2/3)
* schannel: encrypted data buffer: offset 3742 length 4096
* schannel: sending next handshake data: sending 214 bytes...
* schannel: SSL/TLS connection with eastasia.api.cognitive.microsoft.com port 443 (step 2/3)
* schannel: encrypted data buffer: offset 607 length 4096
* schannel: SSL/TLS handshake complete
* schannel: SSL/TLS connection with eastasia.api.cognitive.microsoft.com port 443 (step 3/3)
* ALPN, server did not agree to a protocol
* schannel: incremented credential handle refcount = 1
* schannel: stored credential handle in session cache
> POST /vision/v1.0/analyze?visualFeatures=Categories HTTP/1.1
> Host: eastasia.api.cognitive.microsoft.com
> User-Agent: curl/7.49.0
> Accept: */*
> Content-Type: application/json
> Ocp-Apim-Subscription-Key: ffcd240d42fa4fe98bf0286120fb2801
> Content-Length: 6
>
* upload completely sent off: 6 out of 6 bytes
* schannel: client wants to read 16384 bytes
* schannel: encdata_buffer resized 17408
* schannel: encrypted data buffer: offset 0 length 17408
* schannel: encrypted data got 661
* schannel: encrypted data buffer: offset 661 length 17408
* schannel: decrypted data length: 577
* schannel: decrypted data added: 577
* schannel: decrypted data cached: offset 577 length 16384
* schannel: encrypted data buffer: offset 0 length 17408
* schannel: decrypted data buffer: offset 577 length 16384
* schannel: schannel_recv cleanup
* schannel: decrypted data returned 577
* schannel: decrypted data buffer: offset 0 length 16384
< HTTP/1.1 401 Access Denied
< Content-Length: 143
< Content-Type: application/json
< apim-request-id: b2c7db2c-ef12-48fa-a368-307f127be600
< Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
< x-content-type-options: nosniff
< WWW-Authenticate: AzureApiManagementKey realm="https://eastasia.api.cognitive.microsoft.com/vision/v1.0",name="Ocp-Apim-Subscription-Key",type="header"
< Date: Fri, 05 Jan 2018 01:05:18 GMT
<
{ "statusCode": 401, "message": "Access denied due to invalid subscription key. Make sure to provide a valid key for an active subscription." }* Connection #1 to host eastasia.api.cognitive.microsoft.com left intact
* Trying 40.83.104.208...
* Connected to sysnet.blob.core.windows.net (40.83.104.208) port 80 (#2)
> POST /sysnetimages/trip_to_jp_4.png}' HTTP/1.1
> Host: sysnet.blob.core.windows.net
> User-Agent: curl/7.49.0
> Accept: */*
> Content-Type: application/json
> Ocp-Apim-Subscription-Key: ffcd240d42fa4fe98bf0286120fb2801
> Content-Length: 6
>
* upload completely sent off: 6 out of 6 bytes
< HTTP/1.1 405 The resource doesn't support specified Http Verb.
< Allow: GET,HEAD,PUT,DELETE
< Content-Length: 237
< Content-Type: application/xml
< Server: Microsoft-HTTPAPI/2.0
< x-ms-request-id: 3bee6302-001e-0034-54c1-85891a000000
< Date: Fri, 05 Jan 2018 01:05:20 GMT
<
?xml version="1.0" encoding="utf-8"?><Error><Code>UnsupportedHttpVerb</Code><Message>The resource doesn't support specified Http Verb.
RequestId:3bee6302-001e-0034-54c1-85891a000000
Time:2018-01-05T01:05:21.1833651Z</Message></Error>* Connection #2 to host sysnet.blob.core.windows.net left intact
"Access denied due to invalid subscription key. Make sure to provide a valid key for an active subscription."라는 오류 메시지는, 물론 잘못된 구독 키를 설정했을 때에도 발생하지만 Azure Cognitive 서비스를 신청한 Region이 다른 경우에도 발생합니다.
즉, "
https://westus.api.cognitive.microsoft.com" 지역으로부터 받는 구독 키를 (무심코 예제를 따라 하면서) "
https://eastasia.api.cognitive.microsoft.com" 지역으로 HTTP 요청을 날리면 저렇게 접근 오류가 발생합니다.
또 한 가지 사례로, curl에 JSON 텍스트를 BODY로 설정할 때 다음과 같은 오류가 발생할 수 있습니다.
C:\> curl -g -v POST "https://westus.api.cognitive.microsoft.com/vision/v1.0/analyze?visualFeatures=Categories" -H "Content-Type: application/json" -H "Ocp-Apim-Subscription-Key: ffcd240d42fa4fe98bf0286120fb2801" -d '{"url": "http://sysnet.blob.core.windows.net/sysnetimages/trip_to_jp_4.png"}'
* Rebuilt URL to: POST/
* Could not resolve host: POST
* Closing connection 0
curl: (6) Could not resolve host: POST
* Trying 40.112.254.71...
* Connected to westus.api.cognitive.microsoft.com (40.112.254.71) port 443 (#1)
* schannel: SSL/TLS connection with westus.api.cognitive.microsoft.com port 443 (step 1/3)
* schannel: checking server certificate revocation
* schannel: ALPN, offering http/1.1
* schannel: sending initial handshake data: sending 214 bytes...
* schannel: sent initial handshake data: sent 214 bytes
* schannel: SSL/TLS connection with westus.api.cognitive.microsoft.com port 443 (step 2/3)
* schannel: failed to receive handshake, need more data
* schannel: SSL/TLS connection with westus.api.cognitive.microsoft.com port 443 (step 2/3)
* schannel: encrypted data buffer: offset 3742 length 4096
* schannel: sending next handshake data: sending 214 bytes...
* schannel: SSL/TLS connection with westus.api.cognitive.microsoft.com port 443 (step 2/3)
* schannel: encrypted data buffer: offset 607 length 4096
* schannel: SSL/TLS handshake complete
* schannel: SSL/TLS connection with westus.api.cognitive.microsoft.com port 443 (step 3/3)
* ALPN, server did not agree to a protocol
* schannel: incremented credential handle refcount = 1
* schannel: stored credential handle in session cache
> POST /vision/v1.0/analyze?visualFeatures=Categories HTTP/1.1
> Host: westus.api.cognitive.microsoft.com
> User-Agent: curl/7.49.0
> Accept: */*
> Content-Type: application/json
> Ocp-Apim-Subscription-Key: ffcd240d42fa4fe98bf0286120fb2801
> Content-Length: 6
>
* upload completely sent off: 6 out of 6 bytes
* schannel: client wants to read 16384 bytes
* schannel: encdata_buffer resized 17408
* schannel: encrypted data buffer: offset 0 length 17408
* schannel: encrypted data got 581
* schannel: encrypted data buffer: offset 581 length 17408
* schannel: decrypted data length: 506
* schannel: decrypted data added: 506
* schannel: decrypted data cached: offset 506 length 16384
* schannel: encrypted data buffer: offset 0 length 17408
* schannel: decrypted data buffer: offset 506 length 16384
* schannel: schannel_recv cleanup
* schannel: decrypted data returned 506
* schannel: decrypted data buffer: offset 0 length 16384
< HTTP/1.1 400 Bad Request
< Cache-Control: no-cache
< Pragma: no-cache
< Content-Length: 104
< Content-Type: application/json; charset=utf-8
< Expires: -1
< X-AspNet-Version: 4.0.30319
< X-Powered-By: ASP.NET
< apim-request-id: 813bfccc-a48a-485f-9038-a9d03a20a324
< Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
< x-content-type-options: nosniff
< Date: Fri, 05 Jan 2018 01:16:08 GMT
<
{"code":"BadArgument","requestId":"813bfccc-a48a-485f-9038-a9d03a20a324","message":"JSON format error."}* Connection #1 to host westus.api.cognitive.microsoft.com left intact
* Trying 40.83.104.208...
* Connected to sysnet.blob.core.windows.net (40.83.104.208) port 80 (#2)
> POST /sysnetimages/trip_to_jp_4.png}' HTTP/1.1
> Host: sysnet.blob.core.windows.net
> User-Agent: curl/7.49.0
> Accept: */*
> Content-Type: application/json
> Ocp-Apim-Subscription-Key: ffcd240d42fa4fe98bf0286120fb2801
> Content-Length: 6
>
* upload completely sent off: 6 out of 6 bytes
< HTTP/1.1 405 The resource doesn't support specified Http Verb.
< Allow: GET,HEAD,PUT,DELETE
< Content-Length: 237
< Content-Type: application/xml
< Server: Microsoft-HTTPAPI/2.0
< x-ms-request-id: be36b13a-001e-001a-15c2-8509dd000000
< Date: Fri, 05 Jan 2018 01:16:08 GMT
<
?xml version="1.0" encoding="utf-8"?><Error><Code>UnsupportedHttpVerb</Code><Message>The resource doesn't support specified Http Verb.
RequestId:be36b13a-001e-001a-15c2-8509dd000000
Time:2018-01-05T01:16:08.8793068Z</Message></Error>* Connection #2 to host sysnet.blob.core.windows.net left intact
보는 바와 같이 Request 시의 Content-Length 값이 엉뚱하게 6으로 설정되어 있고, 당연히 "JSON format error."로 "BadArgument" 상황이 발생할 수밖에 없습니다. 검색해 보면,
How to POST JSON data with Curl from Terminal/Commandline to Test Spring REST?
; https://stackoverflow.com/questions/7172784/how-to-post-json-data-with-curl-from-terminal-commandline-to-test-spring-rest
curl의 JSON 텍스트를 명시할 때 작은따옴표를 이용해서는 안 되고 다음과 같이 큰따옴표를 사용하되, 내부의 인용 부호는 esacpe 처리해야 올바로 전달이 됩니다.
curl -g -v POST ...[생략]... -d "{\"url\": \"http://sysnet.blob.core.windows.net/sysnetimages/trip_to_jp_4.png\"}"
이 문제는 실제로 Console Application을 만들어 Main 메서드의 "string [] args"에 넘어온 인자를 살펴보면 내부의 겹따옴표가 제거돼 넘어오는 것을 확인할 수 있습니다. 예를 들어 다음과 같이 인자를 넘기면,
Test.exe '{"url": "http://sysnet.blob.core.windows.net/sysnetimages/trip_to_jp_4.png"}'
args[0] 문자열은 다음과 같이 구해집니다. (Bad Request 오류가 발생하는 것이 당연할 것입니다.)
'{url: http://sysnet.blob.core.windows.net/sysnetimages/trip_to_jp_4.png}'
또는, escape 처리 대신 내부의 큰따옴표를 작은따옴표로 처리하면 됩니다.
curl -g -v POST ...[생략]... -d "{'url': 'http://sysnet.blob.core.windows.net/sysnetimages/trip_to_jp_4.png'}"
심지어 "
How to POST JSON data with Curl from Terminal/Commandline to Test Spring REST?" 글의 덧글에서도 나오지만 많은 인터넷 자료에서 curl의 json 포맷 입력 시 작은따옴표를 묶어서 예시하는 경우가 종종 있는데 그렇게 하면 (아마도 윈도우에서) 정상적인 처리가 안 됩니다.
[2018-10-19 추가] 테스트 인증서를 사용한 https 호출을 하는 경우, "curl: (35) schannel: next InitializeSecurityContext failed: SEC_E_UNTRUSTED_ROOT (0x80090325) - The certificate chain was issued by an authority that is not trusted." 오류가 발생한다면 "-k" 옵션을 설정.
[이 글에 대해서 여러분들과 의견을 공유하고 싶습니다. 틀리거나 미흡한 부분 또는 의문 사항이 있으시면 언제든 댓글 남겨주십시오.]