Add postgres as a db

.gitignore

@@ -1,2 +1,3 @@
 /promlens
 /npm_licenses.tar.bz2
+.idea

README.md

@@ -110,7 +110,7 @@ To save shared links to a local SQLite database, set the `--shared-links.sql.dri
 
 #### MySQL
 
-To save shared links in a MySQL database, set the `--shared-links.sql.driver=mysql` and `--shared-links.sql.dsn=<data source name>` flag (see https://github.com/go-sql-driver/mysql#dsn-data-source-name for MySQL DNS specifications).
+To save shared links in a MySQL database, set the `--shared-links.sql.driver=mysql` and `--shared-links.sql.dsn=<data source name>` flag (see https://github.com/go-sql-driver/mysql#dsn-data-source-name for MySQL DSN specifications).
 
 By default, PromLens will try to auto-create the necessary tables in your MySQL database. This requires the PromLens database user to have `CREATE` permissions. To turn off automatic table creation for MySQL, set the `--no-shared-links.sql.create-tables` flag. If you want to create tables manually, run the following against your PromLens MySQL database:
 
@@ -130,6 +130,28 @@ CREATE TABLE IF NOT EXISTS view(
 );
 ```
 
+#### Postgres
+
+To save shared links in a Postgres database, set the `--shared-links.sql.driver=postgres` and `--shared-links.sql.dsn=<data source name>` flag (see https://pkg.go.dev/github.com/lib/pq#hdr-Connection_String_Parameters for Postgres DSN specifications).
+
+By default, PromLens will try to auto-create the necessary tables in your Postgres database. This requires the PromLens database user to have `CREATE` permissions. To turn off automatic table creation for Postgres, set the `--no-shared-links.sql.create-tables` flag. If you want to create tables manually, run the following against your PromLens Postgres database:
+
+```sql
+CREATE TABLE IF NOT EXISTS link (
+ id SERIAL PRIMARY KEY,
+ created_at timestamptz DEFAULT now(),
+ short_name VARCHAR(11) UNIQUE,
+ page_state TEXT
+);
+
+CREATE TABLE IF NOT EXISTS view(
+ id SERIAL PRIMARY KEY,
+ link_id INTEGER,
+ viewed_at timestamptz DEFAULT now(),
+ FOREIGN KEY(link_id) REFERENCES link(id)
+);
+```
+
 ### Enabling Grafana datasource integration
 
 To enable selection of datasources from an existing Grafana installation, set the `--grafana.url` flag to the URL of your Grafana installation, as well as either the `--grafana.api-token` flag (providing an API token directly as a flag) or the `--grafana.api-token-file` flag (providing an API token from a file).

cmd/promlens/main.go

@@ -94,8 +94,8 @@ func getLinkSharer(logger log.Logger, gcsBucket string, sqlDriver string, sqlDSN
  }
 
  if sqlDSN != "" {
- if sqlDriver != "mysql" && sqlDriver != "sqlite" {
- return nil, errors.Errorf("unsupported SQL driver %q, supported values are 'mysql' and 'sqlite'", sqlDriver)
+ if sqlDriver != "mysql" && sqlDriver != "sqlite" && sqlDriver != "postgres" {
+ return nil, errors.Errorf("unsupported SQL driver %q, supported values are 'mysql', 'postgres' and 'sqlite'", sqlDriver)
  }
 
  s, err := sharer.NewSQLSharer(logger, sqlDriver, sqlDSN, createTables, sqlRetention)

go.mod

@@ -8,6 +8,7 @@ require (
  github.com/go-kit/log v0.2.1
  github.com/go-sql-driver/mysql v1.6.0
  github.com/grafana/regexp v0.0.0-20220304095617-2e8d9baf4ac2
+ github.com/lib/pq v1.10.7
  github.com/pkg/errors v0.9.1
  github.com/prometheus/client_golang v1.13.0
  github.com/prometheus/common v0.37.0
@@ -64,7 +65,7 @@ require (
  golang.org/x/oauth2 v0.0.0-20220909003341-f21342109be1 // indirect
  golang.org/x/sync v0.1.0 // indirect
  golang.org/x/sys v0.0.0-20220919091848-fb04ddd9f9c8 // indirect
- golang.org/x/text v0.3.7 // indirect
+ golang.org/x/text v0.3.8 // indirect
  golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2 // indirect
  google.golang.org/api v0.97.0 // indirect
  google.golang.org/appengine v1.6.7 // indirect

go.sum

@@ -646,6 +646,8 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/leodido/go-urn v1.2.0/go.mod h1:+8+nEpDfqqsY+g338gtMEUOtuK+4dEMhiQEgxpxOKII=
+github.com/lib/pq v1.10.7 h1:p7ZhMD+KsSRozJr34udlUrhboJwWAgCg34+/ZZNvZZw=
+github.com/lib/pq v1.10.7/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/lightstep/lightstep-tracer-common/golang/gogo v0.0.0-20190605223551-bc2310a04743/go.mod h1:qklhhLq1aX+mtWk9cPHPzaBjWImj5ULL6C7HFJtXQMM=
 github.com/lightstep/lightstep-tracer-go v0.18.1/go.mod h1:jlF1pusYV4pidLvZ+XD0UBX0ZE6WURAspgAczcDHrL4=
 github.com/linode/linodego v1.9.1 h1:29UpEPpYcGFnbwiJW8mbk/bjBZpgd/pv68io2IKTo34=
@@ -1257,8 +1259,9 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.4/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/text v0.3.8 h1:nAL+RVCQ9uMn3vJZbV+MRnydTJFPf8qqY42YiA6MrqY=
+golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
 golang.org/x/time v0.0.0-20180412165947-fbb02b2291d2/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=

pkg/sharer/sharer.go

@@ -32,6 +32,7 @@ import (
  // Load SQL drivers.
  _ "github.com/glebarez/go-sqlite"
  _ "github.com/go-sql-driver/mysql"
+ _ "github.com/lib/pq"
 )
 
 const maxPageStateSize = 512 * 1024
@@ -167,7 +168,34 @@ func NewSQLSharer(logger log.Logger, driver string, dsn string, createTables boo
  return nil, fmt.Errorf("Error creating view table: %v", err)
  }
  }
+ case "postgres":
+ db.SetConnMaxLifetime(0)
+ db.SetMaxIdleConns(3)
+ db.SetMaxOpenConns(3)
 
+ if createTables {
+ _, err = db.Exec(`
+ CREATE TABLE IF NOT EXISTS link (
+ id SERIAL PRIMARY KEY,
+ created_at timestamptz DEFAULT now(),
+ short_name VARCHAR(11) UNIQUE,
+ page_state TEXT
+ )`)
+ if err != nil {
+ return nil, fmt.Errorf("error creating link table: %v", err)
+ }
+ _, err = db.Exec(`
+ CREATE TABLE IF NOT EXISTS view(
+ id SERIAL PRIMARY KEY,
+ link_id INT,
+ viewed_at timestamptz DEFAULT now(),
+ FOREIGN KEY(link_id) REFERENCES link(id) ON DELETE CASCADE
+ )`,
+ )
+ if err != nil {
+ return nil, fmt.Errorf("Error creating view table: %v", err)
+ }
+ }
  case "sqlite":
  _, err := db.Exec("PRAGMA foreign_keys = ON")
  if err != nil {
@@ -238,13 +266,15 @@ func NewSQLSharer(logger log.Logger, driver string, dsn string, createTables boo
 }
 
 func (s SQLSharer) cleanupOldLinks(retention time.Duration) (int64, error) {
- timestampFn := "DATETIME"
- if s.driver == "mysql" {
- timestampFn = "TIMESTAMP"
+ var query string
+ if s.driver == "postgres" {
+ query = `DELETE FROM link WHERE created_at < $1::timestamptz`
+ } else if s.driver == "mysql" {
+ query = `DELETE FROM link WHERE created_at < TIMESTAMP(?)`
+ } else {
+ query = `DELETE FROM link WHERE created_at < DATETIME(?)`
  }
-
- res, err := s.db.Exec(`
- DELETE FROM link WHERE created_at < `+timestampFn+`(?)`,
+ res, err := s.db.Exec(query,
  time.Now().Add(-retention),
  )
  if err != nil {
@@ -266,7 +296,13 @@ func (s SQLSharer) CreateLink(name string, pageState string) error {
  return fmt.Errorf("error beginning transaction: %v", err)
  }
  id := 0
- err = tx.QueryRow("SELECT id FROM link WHERE short_name = ?", name).Scan(&id)
+ var query string
+ if s.driver == "postgres" {
+ query = "SELECT id FROM link WHERE short_name = $1"
+ } else {
+ query = "SELECT id FROM link WHERE short_name = ?"
+ }
+ err = tx.QueryRow(query, name).Scan(&id)
  if err == nil {
  // TODO: Check rollback errors.
  _ = tx.Rollback()
@@ -280,8 +316,12 @@ func (s SQLSharer) CreateLink(name string, pageState string) error {
  _ = tx.Rollback()
  return fmt.Errorf("error checking for link existence: %v", err)
  }
-
- _, err = tx.Exec("INSERT INTO link(short_name, page_state) values(?, ?)", name, pageState)
+ if s.driver == "postgres" {
+ query = "INSERT INTO link(short_name, page_state) values($1, $2)"
+ } else {
+ query = "INSERT INTO link(short_name, page_state) values(?, ?)"
+ }
+ _, err = tx.Exec(query, name, pageState)
  if err != nil {
  // TODO: Check rollback errors.
  _ = tx.Rollback()
@@ -299,8 +339,13 @@ func (s SQLSharer) GetLink(name string) (pageState string, err error) {
  linkLookupErrors.Inc()
  }
  }()
-
- stmt, err := s.db.Prepare("SELECT id, page_state FROM link WHERE short_name = ?")
+ var query string
+ if s.driver == "postgres" {
+ query = "SELECT id, page_state FROM link WHERE short_name = $1"
+ } else {
+ query = "SELECT id, page_state FROM link WHERE short_name = ?"
+ }
+ stmt, err := s.db.Prepare(query)
  if err != nil {
  return "", fmt.Errorf("error preparing statement: %v", err)
  }
@@ -313,7 +358,12 @@ func (s SQLSharer) GetLink(name string) (pageState string, err error) {
  return "", err
  }
 
- _, err = s.db.Exec("INSERT INTO view(link_id) values(?)", id)
+ if s.driver == "postgres" {
+ query = "INSERT INTO view(link_id) values($1)"
+ } else {
+ query = "INSERT INTO view(link_id) values(?)"
+ }
+ _, err = s.db.Exec(query, id)
  if err != nil {
  return "", fmt.Errorf("error inserting view: %v", err)
  }