refac: move postgres initialization to separate dir

migra-cli/src/commands/apply.rs

@@ -1,5 +1,5 @@
 use crate::config::Config;
-use crate::database::PostgresConnection;
+use crate::databases::*;
 use crate::migration::{DatabaseMigrationManager, MigrationManager};
 use crate::opts::ApplyCommandOpt;
 use crate::path::PathBuilder;

migra-cli/src/commands/downgrade.rs

@@ -1,6 +1,6 @@
 use crate::config::Config;
-use crate::database::PostgresConnection;
 use crate::migration::{DatabaseMigrationManager, MigrationManager, MigrationNames};
+use crate::databases::*;
 use crate::StdResult;
 use std::convert::TryFrom;
 

migra-cli/src/commands/list.rs

@@ -1,5 +1,6 @@
 use crate::config::Config;
-use crate::database::{DatabaseConnection, PostgresConnection};
+use crate::database::DatabaseConnection;
+use crate::databases::*;
 use crate::error::{ErrorKind, StdResult};
 use crate::migration::{filter_pending_migrations, Migration, MigrationManager, MigrationNames};
 

migra-cli/src/commands/upgrade.rs

@@ -1,4 +1,4 @@
-use crate::database::PostgresConnection;
+use crate::databases::*;
 use crate::migration::{
     filter_pending_migrations, DatabaseMigrationManager, Migration, MigrationManager,
     MigrationNames,

migra-cli/src/database.rs

@@ -1,7 +1,4 @@
-use crate::config::Config;
 use crate::StdResult;
-use postgres::{Client, NoTls};
-use std::convert::TryFrom;
 
 pub trait ToSql {
     fn to_sql(&self) -> String;
@@ -17,13 +14,6 @@ pub trait TryFromSql<QueryResultRow>: Sized {
     fn try_from_sql(row: QueryResultRow) -> StdResult<Self>;
 }
 
-impl TryFromSql<postgres::Row> for String {
-    fn try_from_sql(row: postgres::Row) -> StdResult<Self> {
-        let res: String = row.get(0);
-        Ok(res)
-    }
-}
-
 pub trait DatabaseConnection: Sized {
     type QueryResultRow;
     type QueryResult;
@@ -42,67 +32,3 @@ pub trait DatabaseConnection: Sized {
     where
         OutputItem: ?Sized + TryFromSql<Self::QueryResultRow>;
 }
-
-pub struct PostgresConnection {
-    client: Client,
-}
-
-impl TryFrom<&Config> for PostgresConnection {
-    type Error = Box<dyn std::error::Error>;
-
-    fn try_from(config: &Config) -> Result<Self, Self::Error> {
-        PostgresConnection::open(&config.database_connection_string()?)
-    }
-}
-
-impl DatabaseConnection for PostgresConnection {
-    type QueryResultRow = postgres::Row;
-    type QueryResult = Vec<Self::QueryResultRow>;
-
-    fn open(connection_string: &str) -> StdResult<Self> {
-        let client = Client::connect(connection_string, NoTls)?;
-        Ok(PostgresConnection { client })
-    }
-
-    fn batch_execute(&mut self, query: &str) -> StdResult<()> {
-        self.client.batch_execute(query)?;
-        Ok(())
-    }
-
-    fn execute<'b>(&mut self, query: &str, params: &'b [&'b dyn ToSql]) -> StdResult<u64> {
-        let stmt = params
-            .iter()
-            .enumerate()
-            .fold(query.to_string(), |acc, (i, p)| {
-                str::replace(&acc, &format!("${}", i), &p.to_sql())
-            });
-
-        let res = self.client.execute(stmt.as_str(), &[])?;
-        Ok(res)
-    }
-
-    fn query<'b, OutputItem>(
-        &mut self,
-        query: &str,
-        params: &'b [&'b dyn ToSql],
-    ) -> StdResult<Vec<OutputItem>>
-    where
-        OutputItem: ?Sized + TryFromSql<Self::QueryResultRow>,
-    {
-        let stmt = params
-            .iter()
-            .enumerate()
-            .fold(query.to_string(), |acc, (i, p)| {
-                str::replace(&acc, &format!("${}", i), &p.to_sql())
-            });
-
-        let res: Self::QueryResult = self.client.query(stmt.as_str(), &[])?;
-
-        let res = res
-            .into_iter()
-            .map(OutputItem::try_from_sql)
-            .collect::<Result<Vec<OutputItem>, _>>()?;
-
-        Ok(res)
-    }
-}

migra-cli/src/databases/mod.rs

@@ -0,0 +1,3 @@
+mod postgres;
+
+pub use self::postgres::*;

migra-cli/src/databases/postgres.rs

@@ -0,0 +1,95 @@
+
+use crate::migration::{MigrationNames, MigrationManager, is_migrations_table_not_found};
+use postgres::{Client, NoTls};
+use crate::config::Config;
+use std::convert::TryFrom;
+use crate::error::StdResult;
+use crate::database::{TryFromSql, ToSql, DatabaseConnection};
+
+pub struct PostgresConnection {
+    client: Client,
+}
+
+impl TryFrom<&Config> for PostgresConnection {
+    type Error = Box<dyn std::error::Error>;
+
+    fn try_from(config: &Config) -> Result<Self, Self::Error> {
+        PostgresConnection::open(&config.database_connection_string()?)
+    }
+}
+
+impl DatabaseConnection for PostgresConnection {
+    type QueryResultRow = postgres::Row;
+    type QueryResult = Vec<Self::QueryResultRow>;
+
+    fn open(connection_string: &str) -> StdResult<Self> {
+        let client = Client::connect(connection_string, NoTls)?;
+        Ok(PostgresConnection { client })
+    }
+
+    fn batch_execute(&mut self, query: &str) -> StdResult<()> {
+        self.client.batch_execute(query)?;
+        Ok(())
+    }
+
+    fn execute<'b>(&mut self, query: &str, params: &'b [&'b dyn ToSql]) -> StdResult<u64> {
+        let stmt = params
+            .iter()
+            .enumerate()
+            .fold(query.to_string(), |acc, (i, p)| {
+                str::replace(&acc, &format!("${}", i), &p.to_sql())
+            });
+
+        let res = self.client.execute(stmt.as_str(), &[])?;
+        Ok(res)
+    }
+
+    fn query<'b, OutputItem>(
+        &mut self,
+        query: &str,
+        params: &'b [&'b dyn ToSql],
+    ) -> StdResult<Vec<OutputItem>>
+    where
+        OutputItem: ?Sized + TryFromSql<Self::QueryResultRow>,
+    {
+        let stmt = params
+            .iter()
+            .enumerate()
+            .fold(query.to_string(), |acc, (i, p)| {
+                str::replace(&acc, &format!("${}", i), &p.to_sql())
+            });
+
+        let res: Self::QueryResult = self.client.query(stmt.as_str(), &[])?;
+
+        let res = res
+            .into_iter()
+            .map(OutputItem::try_from_sql)
+            .collect::<Result<Vec<OutputItem>, _>>()?;
+
+        Ok(res)
+    }
+}
+
+impl MigrationNames for MigrationManager<PostgresConnection> {
+    fn applied_migration_names(&mut self) -> StdResult<Vec<String>> {
+        let res = self
+            .conn
+            .query(Self::APPLIED_MIGRATIONS_STMT, &[])
+            .or_else(|e| {
+                if is_migrations_table_not_found(&e) {
+                    Ok(Vec::new())
+                } else {
+                    Err(e)
+                }
+            })?;
+
+        Ok(res.into_iter().collect())
+    }
+}
+
+impl TryFromSql<postgres::Row> for String {
+    fn try_from_sql(row: postgres::Row) -> StdResult<Self> {
+        let res: String = row.get(0);
+        Ok(res)
+    }
+}

migra-cli/src/main.rs

@@ -3,6 +3,7 @@
 mod commands;
 mod config;
 mod database;
+mod databases;
 mod error;
 mod migration;
 mod opts;

migra-cli/src/migration.rs

@@ -1,4 +1,4 @@
-use crate::database::{DatabaseConnection, PostgresConnection};
+use crate::database::DatabaseConnection;
 use crate::path::PathBuilder;
 use crate::StdResult;
 use std::fs;
@@ -51,7 +51,7 @@ impl Migration {
 }
 
 pub struct MigrationManager<Conn: DatabaseConnection> {
-    conn: Conn,
+    pub(crate) conn: Conn,
 }
 
 impl<Conn: DatabaseConnection> MigrationManager<Conn> {
@@ -129,23 +129,6 @@ pub trait MigrationNames {
     fn applied_migration_names(&mut self) -> StdResult<Vec<String>>;
 }
 
-impl MigrationNames for MigrationManager<PostgresConnection> {
-    fn applied_migration_names(&mut self) -> StdResult<Vec<String>> {
-        let res = self
-            .conn
-            .query(Self::APPLIED_MIGRATIONS_STMT, &[])
-            .or_else(|e| {
-                if is_migrations_table_not_found(&e) {
-                    Ok(Vec::new())
-                } else {
-                    Err(e)
-                }
-            })?;
-
-        Ok(res.into_iter().collect())
-    }
-}
-
 pub fn filter_pending_migrations(
     migrations: Vec<Migration>,
     applied_migration_names: &[String],