Postman error against the HTTP JSON API

Questions
1

I’m trying to query the HTTP JSON API with Postman, but get the following answer. On some forums they say it’s an error on the server side. Is that true, or I am doing something wrong?

GET http://localhost:7575/v1/query: {
  "Error": "Parse Error: Expected HTTP/",
  "Request Headers": {
    "authorization": "Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwczovL2RhbWwuY29tL2xlZGdlci1hcGkiOnsibGVkZ2VySWQiOiJzYW5kYm94IiwiYXBwbGljYXRpb25JZCI6ImZvb2JhciIsImFjdEFzIjpbImNhcnJpZXIiXX19.E6TKljEjPA-1QxH-oR0k0GSuzbz6IaGrwExvuryUajA",
    "content-type": "application/json",
    "user-agent": "PostmanRuntime/7.29.0",
    "accept": "*/*",
    "postman-token": "253888c3-6822-4915-b96f-c219dc5b7b1d",
    "host": "localhost:7575",
    "accept-encoding": "gzip, deflate, br",
    "connection": "keep-alive"
  },
  "Request Body": "{}"
}
2

I’m not familiar with Postman; is there some sort of debug mode/output that would show you (and us if you share it) the exact content of the HTTP request it sent?

1 Like
3

The JSON API logs would also be very useful.

4

I can copy to clipboard what I included in the question.

This is printed to the console:

GET http://localhost:7575/v1/query
Error: Parse Error: Expected HTTP/
Proxy
id: "822b89ae-343f-4b35-8f46-be6bf32361ff"
disabled: false
host: "127.0.0.1."
match: {…}
pattern: "http://*:*/*"
port: 6865
tunnel: false
authenticate: false
Request Headers
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwczovL2RhbWwuY29tL2xlZGdlci1hcGkiOnsibGVkZ2VySWQiOiJzYW5kYm94IiwiYXBwbGljYXRpb25JZCI6ImZvb2JhciIsImFjdEFzIjpbImNhcnJpZXIiXX19.E6TKljEjPA-1QxH-oR0k0GSuzbz6IaGrwExvuryUajA
Content-Type: application/json
User-Agent: PostmanRuntime/7.29.0
Accept: */*
Postman-Token: 253888c3-6822-4915-b96f-c219dc5b7b1d
Host: localhost:7575
Accept-Encoding: gzip, deflate, br
Connection: keep-alive
Request Body
{}
5

I cannot see any effect of the Potman request in the log:

gyorgybalazsi@BGY init_examples % sh start_json_api.sh
08-08-2022 11:52:34.870 [main] INFO  com.daml.http.Main - Config(ledgerHost=localhost, ledgerPort=6865, address=localhost, httpPort=7575, portFile=None, packageReloadInterval=5 seconds, packageMaxInboundMessageSize=None, maxInboundMessageSize=4194304, tlsConfig=TlsConfiguration(false,None,None,None,None,REQUIRE,false,None), jdbcConfig=None, staticContentConfig=None, allowNonHttps=false, wsConfig=None, nonRepudiationCertificateFile=None, nonRepudiationPrivateKeyFile=None, nonRepudiationPrivateKeyAlgorithm=None, surrogateTpIdCacheMaxEntries=None), context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:35.352 [http-json-ledger-api-akka.actor.default-dispatcher-5] INFO  akka.event.slf4j.Slf4jLogger - Slf4jLogger started 
08-08-2022 11:52:35.724 [http-json-ledger-api-akka.actor.default-dispatcher-9] INFO  com.daml.http.HttpService - HTTP Server pre-startup, context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:36.066 [http-json-ledger-api-akka.actor.default-dispatcher-9] INFO  com.daml.http.LedgerClient - Attempting to connect to the ledger localhost:6865 (600 attempts), context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:36.778 [http-json-ledger-api-akka.actor.default-dispatcher-9] INFO  com.daml.http.LedgerClient - Attempt 1/600 succeeded!, context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:36.783 [http-json-ledger-api-akka.actor.default-dispatcher-9] INFO  com.daml.http.LedgerClient - Attempting to connect to the ledger localhost:6865 (600 attempts), context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:36.792 [http-json-ledger-api-akka.actor.default-dispatcher-9] INFO  com.daml.http.LedgerClient - Attempt 1/600 succeeded!, context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:36.793 [http-json-ledger-api-akka.actor.default-dispatcher-9] INFO  com.daml.http.HttpService - contractDao: None, context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"} 
08-08-2022 11:52:37.663 [http-json-ledger-api-akka.actor.default-dispatcher-11] INFO  com.daml.http.Main - Started server: (ServerBinding(/127.0.0.1:7575),None), context: {instance_uuid: "8d74cdb2-770a-4df7-956f-2946a10bdc90"}
6

What happens if you send the same request via Curl, e.g., curl localhost:7575/v1/query?

7

I get a correct answer:

% curl --location --request GET 'http://localhost:7575/v1/query' \
--header 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwczovL2RhbWwuY29tL2xlZGdlci1hcGkiOnsibGVkZ2VySWQiOiJzYW5kYm94IiwiYXBwbGljYXRpb25JZCI6ImZvb2JhciIsImFjdEFzIjpbImNhcnJpZXIiXX19.E6TKljEjPA-1QxH-oR0k0GSuzbz6IaGrwExvuryUajA' \
--header 'Content-Type: application/json' \
--data-raw '{}'
{"result":[],"status":200}%
8

Sounds like it’s a postman issue.

1 Like
9

May be. Some time ago I used Postman for this purpose.

10

Looks like the HTTP version is missing from the HTTP request line sent by Postman (RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1). The request line should be something like

GET http://localhost:7575/v1/query HTTP/1.1

Postman is such a mature tool I’m a bit surprised by the error, there’s probably something we’re overlooking.

1 Like
11

Can you try that curl command again with an added -v at the end, and report the full result?

12

That’s it:

% curl --location --request GET 'http://localhost:7575/v1/query' \
--header 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwczovL2RhbWwuY29tL2xlZGdlci1hcGkiOnsibGVkZ2VySWQiOiJzYW5kYm94IiwiYXBwbGljYXRpb25JZCI6ImZvb2JhciIsImFjdEFzIjpbImNhcnJpZXIiXX19.E6TKljEjPA-1QxH-oR0k0GSuzbz6IaGrwExvuryUajA' \
--header 'Content-Type: application/json' \
--data-raw '{}' -v
*   Trying 127.0.0.1:7575...
* Connected to localhost (127.0.0.1) port 7575 (#0)
> GET /v1/query HTTP/1.1
> Host: localhost:7575
> User-Agent: curl/7.79.1
> Accept: */*
> Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJodHRwczovL2RhbWwuY29tL2xlZGdlci1hcGkiOnsibGVkZ2VySWQiOiJzYW5kYm94IiwiYXBwbGljYXRpb25JZCI6ImZvb2JhciIsImFjdEFzIjpbImNhcnJpZXIiXX19.E6TKljEjPA-1QxH-oR0k0GSuzbz6IaGrwExvuryUajA
> Content-Type: application/json
> Content-Length: 2
> 
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Server: akka-http/10.2.8
< Date: Mon, 08 Aug 2022 13:55:37 GMT
< Transfer-Encoding: chunked
< Content-Type: application/json
< 
* Connection #0 to host localhost left intact
{"result":[],"status":200}%
13

I wanted to double-check that it wasn’t an issue with the response, but it looks well-formed to me.

I don’t know how to help further in the absence of an option for Postman to display detailed logs like these, i.e. that include the exact HTTP message sent.

1 Like
14

Thank you for your effort, I let this go, I can solve my problem with different tools.

15

I ran into this problem just now. I’d like to document the solution that worked for me, in case someone finds this page like I did. In my case…

I had my Postman port number variable set to the wrong port. In my Postman request, I was using {{ApiPort}}, which I had previously configured for the Ledger API, port 6865. When I blindly reused my {{ApiPort}} variable for a new JSON API request, I received the message:

GET http://localhost:6865/v1/query
Error: Parse Error: Expected HTTP/

When I changed the value of {{ApiPort}} to 7575, the GET of the v1/query endpoint returned a proper result and I no longer saw the error message.

This does not appear to have been the case for gyorgybalazsi, but if you make the same mistake I did,… you are welcome! :slight_smile: