feat: add prometheus metrics

README.md

@@ -398,3 +398,7 @@ curl --location 'http://localhost:8000/v1/queues/processed-orders/messages'
 ```
 
 As expected, this queue has only one message that was published with the `status` attribute equal to `"processed"`.
+
+## Prometheus metrics
+
+The Prometheus metrics can be accessed at http://localhost:9090.

domain/config.go

@@ -51,6 +51,8 @@ type Config struct {
 	ServerHost                     string
 	ServerPort                     uint
 	ServerReadHeaderTimeoutSeconds uint
+	MetricsHost                    string
+	MetricsPort                    uint
 	DatabaseURL                    string
 	TestDatabaseURL                string
 	DatabaseMinConns               uint
@@ -68,6 +70,8 @@ func NewConfig() *Config {
 		ServerHost:                     env.GetString("PSQLQUEUE_SERVER_HOST", "0.0.0.0"),
 		ServerPort:                     env.GetUint("PSQLQUEUE_SERVER_PORT", 8000),
 		ServerReadHeaderTimeoutSeconds: env.GetUint("PSQLQUEUE_SERVER_READ_HEADER_TIMEOUT_SECONDS", 60),
+		MetricsHost:                    env.GetString("PSQLQUEUE_METRICS_HOST", "0.0.0.0"),
+		MetricsPort:                    env.GetUint("PSQLQUEUE_METRICS_PORT", 9090),
 		DatabaseURL:                    env.GetString("PSQLQUEUE_DATABASE_URL", ""),
 		TestDatabaseURL:                env.GetString("PSQLQUEUE_TEST_DATABASE_URL", ""),
 		DatabaseMinConns:               env.GetUint("PSQLQUEUE_DATABASE_MIN_CONNS", 0),

env.sample

@@ -3,6 +3,8 @@ PSQLQUEUE_LOG_LEVEL='debug'
 PSQLQUEUE_SERVER_HOST='0.0.0.0'
 PSQLQUEUE_SERVER_PORT='8000'
 PSQLQUEUE_SERVER_READ_HEADER_TIMEOUT_SECONDS='60'
+PSQLQUEUE_METRICS_HOST='0.0.0.0'
+PSQLQUEUE_METRICS_PORT='9090'
 PSQLQUEUE_DATABASE_URL='postgres://psqlqueue:psqlqueue@localhost:5432/psqlqueue?sslmode=disable'
 PSQLQUEUE_TEST_DATABASE_URL='postgres://psqlqueue:psqlqueue@localhost:5432/psqlqueue-test?sslmode=disable'
 PSQLQUEUE_DATABASE_MIN_CONNS='0'

go.mod

@@ -12,7 +12,9 @@ require (
 	github.com/jellydator/validation v1.1.0
 	github.com/joho/godotenv v1.5.1
 	github.com/oklog/ulid/v2 v2.1.0
+	github.com/prometheus/client_golang v1.18.0
 	github.com/samber/slog-gin v1.8.0
+	github.com/slok/go-http-metrics v0.11.0
 	github.com/stretchr/testify v1.8.4
 	github.com/swaggo/files v1.0.1
 	github.com/swaggo/gin-swagger v1.6.0
@@ -25,7 +27,9 @@ require (
 	github.com/KyleBanks/depth v1.2.1 // indirect
 	github.com/PuerkitoBio/purell v1.1.1 // indirect
 	github.com/PuerkitoBio/urlesc v0.0.0-20170810143723-de5bf2ad4578 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/bytedance/sonic v1.9.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
@@ -38,7 +42,7 @@ require (
 	github.com/go-openapi/swag v0.19.15 // indirect
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
-	github.com/go-playground/validator/v10 v10.14.0 // indirect
+	github.com/go-playground/validator/v10 v10.15.5 // indirect
 	github.com/goccy/go-json v0.10.2 // indirect
 	github.com/google/uuid v1.4.0 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
@@ -59,14 +63,18 @@ require (
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/cpuid/v2 v2.2.4 // indirect
 	github.com/leodido/go-urn v1.2.4 // indirect
-	github.com/mailru/easyjson v0.7.6 // indirect
-	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
-	github.com/pelletier/go-toml/v2 v2.0.8 // indirect
+	github.com/pelletier/go-toml/v2 v2.1.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/prometheus/client_model v0.5.0 // indirect
+	github.com/prometheus/common v0.45.0 // indirect
+	github.com/prometheus/procfs v0.12.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
-	github.com/stretchr/objx v0.5.0 // indirect
+	github.com/stretchr/objx v0.5.1 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/ugorji/go/codec v1.2.11 // indirect
 	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect

go.sum

@@ -19,9 +19,13 @@ github.com/allisson/sqlquery v1.3.1 h1:D/DBvZRqmw4bPP5v5zrNooVAgHtU1pZf/CT5mMrW3
 github.com/allisson/sqlquery v1.3.1/go.mod h1:SfAu/CPxjTQU7cYVGljdFtwT8s0QZ/6BM6bzrxenoBo=
 github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d h1:Byv0BzEl3/e6D5CLfI0j/7hiIEtvGVFPCZ7Ei2oq8iQ=
 github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/bytedance/sonic v1.5.0/go.mod h1:ED5hyg4y6t3/9Ku1R6dU/4KyJ48DZ4jPhfY1O2AihPM=
 github.com/bytedance/sonic v1.9.1 h1:6iJ6NqdoxCDr6mbY8h18oSO+cShGSMRGCEo7F2h0x8s=
 github.com/bytedance/sonic v1.9.1/go.mod h1:i736AoUSYt75HyZLoJW9ERYxcy6eaN6h4BZXU064P/U=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/chenzhuoyu/base64x v0.0.0-20211019084208-fb5309c8db06/go.mod h1:DH46F32mSOjUmXrMHnKwZdA8wcEefY7UVqBKYGjpdQY=
 github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 h1:qSGYFH7+jGhDF8vLC+iwCD4WpbV1EBDSzWkJODFLams=
 github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311/go.mod h1:b583jCggY9gE99b6G5LEC39OIiVsWj+R97kbl5odCEk=
@@ -76,8 +80,8 @@ github.com/go-playground/locales v0.14.1 h1:EWaQ/wswjilfKLTECiXz7Rh+3BjFhfDFKv/o
 github.com/go-playground/locales v0.14.1/go.mod h1:hxrqLVvrK65+Rwrd5Fc6F2O76J/NuW9t0sjnWqG1slY=
 github.com/go-playground/universal-translator v0.18.1 h1:Bcnm0ZwsGyWbCzImXv+pAJnYK9S473LQFuzCbDbfSFY=
 github.com/go-playground/universal-translator v0.18.1/go.mod h1:xekY+UJKNuX9WP91TpwSH2VMlDf28Uj24BCp08ZFTUY=
-github.com/go-playground/validator/v10 v10.14.0 h1:vgvQWe3XCz3gIeFDm/HnTIbj6UGmg/+t63MyGU2n5js=
-github.com/go-playground/validator/v10 v10.14.0/go.mod h1:9iXMNT7sEkjXb0I+enO7QXmzG6QCsPWY4zveKFVRSyU=
+github.com/go-playground/validator/v10 v10.15.5 h1:LEBecTWb/1j5TNY1YYG2RcOUN3R7NLylN+x8TTueE24=
+github.com/go-playground/validator/v10 v10.15.5/go.mod h1:9iXMNT7sEkjXb0I+enO7QXmzG6QCsPWY4zveKFVRSyU=
 github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/melR3HDY=
 github.com/goccy/go-json v0.10.2 h1:CrxCmQqYDkv1z7lO7Wbh2HN93uovUHgrECaO5ZrCXAU=
 github.com/goccy/go-json v0.10.2/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MGFi0w8I=
@@ -177,8 +181,8 @@ github.com/klauspost/cpuid/v2 v2.2.4/go.mod h1:RVVoqg1df56z8g3pUjL/3lE5UfnlrJX8t
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/konsorten/go-windows-terminal-sequences v1.0.2/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
-github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0=
-github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/pty v1.1.8/go.mod h1:O1sed60cT9XZ5uDucP5qwvh+TE3NnUj51EiZO/lmSfw=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
@@ -194,15 +198,18 @@ github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
 github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/mailru/easyjson v0.0.0-20190614124828-94de47d64c63/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
 github.com/mailru/easyjson v0.0.0-20190626092158-b2ccc519800e/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
-github.com/mailru/easyjson v0.7.6 h1:8yTIVnZgCoiM1TgqoeTl+LfU5Jg6/xL3QhGQnimLYnA=
 github.com/mailru/easyjson v0.7.6/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
+github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=
+github.com/mailru/easyjson v0.7.7/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
 github.com/mattn/go-colorable v0.1.1/go.mod h1:FuOcm+DKB9mbwrcAfNl7/TZVBZ6rcnceauSikq3lYCQ=
 github.com/mattn/go-colorable v0.1.6/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-isatty v0.0.5/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.7/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
-github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
-github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
+github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0 h1:jWpvCLoY8Z/e3VKvlsiIGKtc+UG6U5vzxaoagmhXfyg=
+github.com/matttproud/golang_protobuf_extensions/v2 v2.0.0/go.mod h1:QUyp042oQthUoa9bqDv0ER0wrtXnBruoNd7aNjkbP+k=
 github.com/moby/term v0.5.0 h1:xt8Q1nalod/v7BqbG21f8mQPqH+xAaC9C3N3wfWbVP0=
 github.com/moby/term v0.5.0/go.mod h1:8FzsFHVUBGZdbDsJw/ot+X+d5HLUbvklYLJ9uGfcI3Y=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
@@ -222,16 +229,24 @@ github.com/opencontainers/image-spec v1.0.2/go.mod h1:BtxoFyWECRxE4U/7sNtV5W15zM
 github.com/pashagolub/pgxmock/v2 v2.6.0 h1:Dk07FlzdMOrqdxrelmEeWP9uqcDm757HZWrIwyvdPsE=
 github.com/pashagolub/pgxmock/v2 v2.6.0/go.mod h1:FsT+LxxrLNqeRWHzk2SBrSW+5m+kXLcKoVZxigHVHeI=
 github.com/pborman/getopt v0.0.0-20170112200414-7148bc3a4c30/go.mod h1:85jBQOZwpVEaDAr341tbn15RS4fCAsIst0qp7i8ex1o=
-github.com/pelletier/go-toml/v2 v2.0.8 h1:0ctb6s9mE31h0/lhu+J6OPmVeDxJn+kYnJc2jZR9tGQ=
-github.com/pelletier/go-toml/v2 v2.0.8/go.mod h1:vuYfssBdrU2XDZ9bYydBu6t+6a6PYNcZljzZR9VXg+4=
+github.com/pelletier/go-toml/v2 v2.1.0 h1:FnwAJ4oYMvbT/34k9zzHuZNrhlz48GB3/s6at6/MHO4=
+github.com/pelletier/go-toml/v2 v2.1.0/go.mod h1:tJU2Z3ZkXwnxa4DPO899bsyIoywizdUvyaeZurnPPDc=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/prometheus/client_golang v1.18.0 h1:HzFfmkOzH5Q8L8G+kSJKUx5dtG87sewO+FoDDqP5Tbk=
+github.com/prometheus/client_golang v1.18.0/go.mod h1:T+GXkCk5wSJyOqMIzVgvvjFDlkOQntgjkJWKrN5txjA=
+github.com/prometheus/client_model v0.5.0 h1:VQw1hfvPvk3Uv6Qf29VrPF32JB6rtbgI6cYPYQjL0Qw=
+github.com/prometheus/client_model v0.5.0/go.mod h1:dTiFglRmd66nLR9Pv9f0mZi7B7fk5Pm3gvsjB5tr+kI=
+github.com/prometheus/common v0.45.0 h1:2BGz0eBc2hdMDLnO/8n0jeB3oPrt2D08CekT0lneoxM=
+github.com/prometheus/common v0.45.0/go.mod h1:YJmSTw9BoKxJplESWWxlbyttQR4uaEcGyv9MZjVOJsY=
+github.com/prometheus/procfs v0.12.0 h1:jluTpSng7V9hY0O2R9DzzJHYb2xULk9VTR1V1R/k6Bo=
+github.com/prometheus/procfs v0.12.0/go.mod h1:pcuDEFsWDnvcgNzo4EEweacyhjeA9Zk3cnaOZAZEfOo=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
-github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
-github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
+github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
+github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
 github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
 github.com/rs/zerolog v1.13.0/go.mod h1:YbFCdg8HfsridGWAh22vktObvhZbQsZXe4/zB0OKkWU=
 github.com/rs/zerolog v1.15.0/go.mod h1:xYTKnLHcpfU2225ny5qZjxnj9NvkumZYjJHlAThCjNc=
@@ -245,12 +260,15 @@ github.com/shopspring/decimal v1.2.0 h1:abSATXmQEYyShuxI4/vyW3tV1MrKAJzCZ/0zLUXY
 github.com/shopspring/decimal v1.2.0/go.mod h1:DKyhrW/HYNuLGql+MJL6WCR6knT2jwCFRcu2hWCYk4o=
 github.com/sirupsen/logrus v1.4.1/go.mod h1:ni0Sbl8bgC9z8RoU9G6nDWqqs/fq4eDPysMBDgk/93Q=
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+github.com/slok/go-http-metrics v0.11.0 h1:ABJUpekCZSkQT1wQrFvS4kGbhea/w6ndFJaWJeh3zL0=
+github.com/slok/go-http-metrics v0.11.0/go.mod h1:ZGKeYG1ET6TEJpQx18BqAJAvxw9jBAZXCHU7bWQqqAc=
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-github.com/stretchr/objx v0.5.0 h1:1zr/of2m5FGMsad5YfcqgdqdWrIhu+EBEJRhR1U7z/c=
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+github.com/stretchr/objx v0.5.1 h1:4VhoImhV/Bm0ToFkXFi8hXNXwpDRZ/ynw3amt82mzq0=
+github.com/stretchr/objx v0.5.1/go.mod h1:/iHQpkQwBD6DLUmQ4pE+s1TXdob1mORJ4/UFdrifcy0=
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 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
@@ -261,7 +279,6 @@ github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
-github.com/stretchr/testify v1.8.3/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/swaggo/files v1.0.1 h1:J1bVJ4XHZNq0I46UU90611i9/YzdrF7x92oX1ig5IdE=

http/setup.go

@@ -11,19 +11,28 @@ import (
 	"time"
 
 	"github.com/gin-gonic/gin"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	sloggin "github.com/samber/slog-gin"
+	metrics "github.com/slok/go-http-metrics/metrics/prometheus"
+	"github.com/slok/go-http-metrics/middleware"
+	ginmiddleware "github.com/slok/go-http-metrics/middleware/gin"
 	swaggerfiles "github.com/swaggo/files"
 	ginSwagger "github.com/swaggo/gin-swagger"
 
 	docs "github.com/allisson/psqlqueue/docs"
 	"github.com/allisson/psqlqueue/domain"
 )
 
+var prometheusMiddleware = middleware.New(middleware.Config{
+	Recorder: metrics.NewRecorder(metrics.Config{}),
+})
+
 func SetupRouter(logger *slog.Logger, queueHandler *QueueHandler, messageHandler *MessageHandler, topicHandler *TopicHandler, subscriptionHandler *SubscriptionHandler, healthCheckHandler *HealthCheckHandler) *gin.Engine {
 	// router setup
 	gin.SetMode(gin.ReleaseMode)
 	router := gin.New()
 	router.Use(sloggin.New(logger), gin.Recovery())
+	router.Use(ginmiddleware.Handler("", prometheusMiddleware))
 
 	// swagger config
 	docs.SwaggerInfo.Title = "PSQL Queue API"
@@ -72,17 +81,34 @@ func SetupRouter(logger *slog.Logger, queueHandler *QueueHandler, messageHandler
 
 // RunServer runs an HTTP server based on config and router.
 func RunServer(ctx context.Context, cfg *domain.Config, router *gin.Engine) {
+
 	// Create context that listens for the interrupt signal from the OS.
 	ctx, stop := signal.NotifyContext(ctx, syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 
+	metricsSrv := &http.Server{
+		Addr:              fmt.Sprintf("%s:%d", cfg.MetricsHost, cfg.MetricsPort),
+		Handler:           promhttp.Handler(),
+		ReadHeaderTimeout: time.Second * time.Duration(cfg.ServerReadHeaderTimeoutSeconds),
+	}
 	srv := &http.Server{
 		Addr:              fmt.Sprintf("%s:%d", cfg.ServerHost, cfg.ServerPort),
 		Handler:           router,
 		ReadHeaderTimeout: time.Second * time.Duration(cfg.ServerReadHeaderTimeoutSeconds),
 	}
 
-	// Initializing the server in a goroutine so that
+	// Initializing the metrics server in a goroutine so that
+	// it won't block the graceful shutdown handling below
+	go func() {
+		slog.Info("metrics server starting", "host", cfg.MetricsHost, "port", cfg.MetricsPort)
+
+		if err := metricsSrv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			slog.Error("metrics server listen error", err)
+			os.Exit(1)
+		}
+	}()
+
+	// Initializing the http server in a goroutine so that
 	// it won't block the graceful shutdown handling below
 	go func() {
 		slog.Info("http server starting", "host", cfg.ServerHost, "port", cfg.ServerPort)
@@ -98,16 +124,20 @@ func RunServer(ctx context.Context, cfg *domain.Config, router *gin.Engine) {
 
 	// Restore default behavior on the interrupt signal and notify user of shutdown.
 	stop()
-	slog.Info("http server shutting down gracefully, press Ctrl+C again to force")
+	slog.Info("server shutting down gracefully, press Ctrl+C again to force")
 
 	// The context is used to inform the server it has 5 seconds to finish
 	// the request it is currently handling
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()
+	if err := metricsSrv.Shutdown(ctx); err != nil {
+		slog.Error("metrics server forced to shutdown: ", err)
+		os.Exit(1)
+	}
 	if err := srv.Shutdown(ctx); err != nil {
 		slog.Error("http server forced to shutdown: ", err)
 		os.Exit(1)
 	}
 
-	slog.Info("http server exiting")
+	slog.Info("server exiting")
 }