syntax error: unexpected $end when setting server.http_path_prefix

[tarokkk]

Describe the bug
When you set http_path_prefix Loki response with:
error parsing labels: parse error : syntax error: unexpected $end

To Reproduce
Installed Loki from latest chart and port-forwarded to localhost-
loki-0.29.0 v1.5.0

Example curl (working)

$ curl -v -H "Content-Type: application/json" -XPOST -s "http://localhost:3100/loki/api/v1/push" --data-raw \
  '{"streams": [{ "stream": { "foo": "bar2" }, "values": [ [ "1591260992000000000", "fizzbuzz" ] ] }]}'
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3100 (#0)
> POST /loki/api/v1/push HTTP/1.1
> Host: localhost:3100
> User-Agent: curl/7.64.1
> Accept: */*
> Content-Type: application/json
> Content-Length: 99
>
* upload completely sent off: 99 out of 99 bytes
< HTTP/1.1 204 No Content
< Date: Thu, 04 Jun 2020 08:56:49 GMT
<
* Connection #0 to host localhost left intact
* Closing connection 0

Setting the http_path_prefix to loki-server

$ curl -v -H "Content-Type: application/json" -XPOST -s "http://localhost:3100/loki-server/loki/api/v1/push" --data-raw \
  '{"streams": [{ "stream": { "foo": "bar2" }, "values": [ [ "1591260992000000000", "fizzbuzz" ] ] }]}'
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 3100 (#0)
> POST /loki-server/loki/api/v1/push HTTP/1.1
> Host: localhost:3100
> User-Agent: curl/7.64.1
> Accept: */*
> Content-Type: application/json
> Content-Length: 99
>
* upload completely sent off: 99 out of 99 bytes
< HTTP/1.1 400 Bad Request
< Content-Type: text/plain; charset=utf-8
< X-Content-Type-Options: nosniff
< Date: Thu, 04 Jun 2020 09:00:23 GMT
< Content-Length: 66
<
error parsing labels: parse error : syntax error: unexpected $end
* Connection #0 to host localhost left intact
* Closing connection 0

Expected behavior
It should work like without the settings.

Environment:

• Infrastructure: Kubernetes
• Deployment tool: Helm

Config:

auth_enabled: false
chunk_store_config:
  max_look_back_period: 0s
ingester:
  chunk_block_size: 262144
  chunk_idle_period: 3m
  chunk_retain_period: 1m
  lifecycler:
    ring:
      kvstore:
        store: inmemory
      replication_factor: 1
  max_transfer_retries: 0
limits_config:
  enforce_metric_name: false
  reject_old_samples: true
  reject_old_samples_max_age: 168h
schema_config:
  configs:
  - from: "2018-04-15"
    index:
      period: 168h
      prefix: index_
    object_store: filesystem
    schema: v9
    store: boltdb
server:
  http_listen_port: 3100
  http_path_prefix: /loki-server
storage_config:
  boltdb:
    directory: /data/loki/index
  filesystem:
    directory: /data/loki/chunks
table_manager:
  retention_deletes_enabled: false
  retention_period: 0s%

[sandeepsukhani]

The problem is with detecting the version from the API here.
I think support for a prefix could be hard considering the endpoints being hardcoded at some of the places in query-frontend like here.

[cyriltovena]

All good point @sandeepsukhani, I think we can do it for the frontend, considering the config is shared.

[slim-bean]

@tarokkk in the future please avoid asking your peers to thumbs up an issue in an attempt to game the priority, this is a good way to find yourself at the bottom of the priority list....

[stale]

This issue has been automatically marked as stale because it has not had any activity in the past 30 days. It will be closed in 7 days if no further activity occurs. Thank you for your contributions.