refac: preparatory work for subsequent changes

Moved the main logic such as running a command or getting a config
into it.

Changed incoming paramenters for commands.

migra-cli/src/app.rs

@@ -0,0 +1,58 @@
+use crate::commands;
+use crate::error::*;
+use crate::opts::Command;
+use crate::AppOpt;
+use crate::Config;
+use std::path::PathBuf;
+use structopt::StructOpt;
+
+#[derive(Debug, Clone)]
+pub(crate) struct App {
+    app_opt: AppOpt,
+}
+
+impl App {
+    pub fn new(app_opt: AppOpt) -> Self {
+        App { app_opt }
+    }
+
+    pub fn config_path(&self) -> Option<&PathBuf> {
+        self.app_opt.config_path.as_ref()
+    }
+
+    pub fn config(&self) -> MigraResult<Config> {
+        Config::read(self.config_path())
+    }
+
+    pub fn run_command(&self) -> StdResult<()> {
+        match self.app_opt.command.clone() {
+            Command::Init => {
+                commands::initialize_migra_manifest(self)?;
+            }
+            Command::Apply(cmd_opts) => {
+                commands::apply_sql(self, cmd_opts)?;
+            }
+            Command::Make(cmd_opts) => {
+                commands::make_migration(self, cmd_opts)?;
+            }
+            Command::List => {
+                commands::print_migration_lists(self)?;
+            }
+            Command::Upgrade(cmd_opts) => {
+                commands::upgrade_pending_migrations(self, cmd_opts)?;
+            }
+            Command::Downgrade(cmd_opts) => {
+                commands::rollback_applied_migrations(self, cmd_opts)?;
+            }
+            Command::Completions(cmd_opts) => {
+                AppOpt::clap().gen_completions_to(
+                    env!("CARGO_BIN_NAME"),
+                    cmd_opts.into(),
+                    &mut std::io::stdout(),
+                );
+            }
+        }
+
+        Ok(())
+    }
+}

migra-cli/src/commands/apply.rs

@@ -1,18 +1,19 @@
-use crate::config::Config;
+use crate::app::App;
 use crate::database::prelude::*;
 use crate::database::transaction::with_transaction;
 use crate::database::{DatabaseConnectionManager, MigrationManager};
 use crate::opts::ApplyCommandOpt;
 use crate::StdResult;
 
-pub(crate) fn apply_sql(config: Config, opts: ApplyCommandOpt) -> StdResult<()> {
+pub(crate) fn apply_sql(app: &App, cmd_opts: ApplyCommandOpt) -> StdResult<()> {
+    let config = app.config()?;
     let mut connection_manager = DatabaseConnectionManager::connect(&config.database)?;
     let conn = connection_manager.connection();
 
     let migration_manager = MigrationManager::new();
 
     let file_path = {
-        let mut file_path = config.directory_path().join(opts.file_name);
+        let mut file_path = config.directory_path().join(cmd_opts.file_name);
         if file_path.extension().is_none() {
             file_path.set_extension("sql");
         }

migra-cli/src/commands/downgrade.rs

@@ -1,4 +1,4 @@
-use crate::config::Config;
+use crate::app::App;
 use crate::database::prelude::*;
 use crate::database::transaction::with_transaction;
 use crate::database::{DatabaseConnectionManager, MigrationManager};
@@ -6,10 +6,8 @@ use crate::opts::DowngradeCommandOpt;
 use crate::StdResult;
 use std::cmp;
 
-pub(crate) fn rollback_applied_migrations(
-    config: Config,
-    opts: DowngradeCommandOpt,
-) -> StdResult<()> {
+pub(crate) fn rollback_applied_migrations(app: &App, opts: DowngradeCommandOpt) -> StdResult<()> {
+    let config = app.config()?;
     let mut connection_manager = DatabaseConnectionManager::connect(&config.database)?;
     let conn = connection_manager.connection();
     let migration_manager = MigrationManager::new();

migra-cli/src/commands/init.rs

@@ -1,9 +1,12 @@
+use crate::app::App;
 use crate::config::{Config, MIGRA_TOML_FILENAME};
 use crate::StdResult;
 use std::path::PathBuf;
 
-pub(crate) fn initialize_migra_manifest(config_path: Option<PathBuf>) -> StdResult<()> {
-    let config_path = config_path
+pub(crate) fn initialize_migra_manifest(app: &App) -> StdResult<()> {
+    let config_path = app
+        .config_path()
+        .cloned()
         .map(|mut config_path| {
             let ext = config_path.extension();
             if config_path.is_dir() || ext.is_none() {

migra-cli/src/commands/list.rs

@@ -1,4 +1,4 @@
-use crate::config::Config;
+use crate::app::App;
 use crate::database::migration::filter_pending_migrations;
 use crate::database::prelude::*;
 use crate::database::{DatabaseConnectionManager, Migration, MigrationManager};
@@ -6,7 +6,8 @@ use crate::error::{Error, StdResult};
 
 const EM_DASH: char = '—';
 
-pub(crate) fn print_migration_lists(config: Config) -> StdResult<()> {
+pub(crate) fn print_migration_lists(app: &App) -> StdResult<()> {
+    let config = app.config()?;
     let applied_migration_names = match config.database.connection_string() {
         Ok(ref database_connection_string) => {
             let mut connection_manager = DatabaseConnectionManager::connect_with_string(

migra-cli/src/commands/make.rs

@@ -1,10 +1,11 @@
+use crate::app::App;
 use crate::opts::MakeCommandOpt;
-use crate::Config;
 use crate::StdResult;
 use chrono::Local;
 use std::fs;
 
-pub(crate) fn make_migration(config: Config, opts: MakeCommandOpt) -> StdResult<()> {
+pub(crate) fn make_migration(app: &App, opts: MakeCommandOpt) -> StdResult<()> {
+    let config = app.config()?;
     let now = Local::now().format("%y%m%d%H%M%S");
 
     let migration_name: String = opts

migra-cli/src/commands/upgrade.rs

@@ -1,11 +1,12 @@
+use crate::app::App;
 use crate::database::migration::*;
 use crate::database::transaction::with_transaction;
 use crate::database::DatabaseConnectionManager;
 use crate::opts::UpgradeCommandOpt;
-use crate::Config;
 use crate::StdResult;
 
-pub(crate) fn upgrade_pending_migrations(config: Config, opts: UpgradeCommandOpt) -> StdResult<()> {
+pub(crate) fn upgrade_pending_migrations(app: &App, opts: UpgradeCommandOpt) -> StdResult<()> {
+    let config = app.config()?;
     let mut connection_manager = DatabaseConnectionManager::connect(&config.database)?;
     let conn = connection_manager.connection();
 

migra-cli/src/config.rs

@@ -134,12 +134,12 @@ fn recursive_find_project_root() -> MigraResult<PathBuf> {
 }
 
 impl Config {
-    pub fn read(config_path: Option<PathBuf>) -> MigraResult<Config> {
+    pub fn read(config_path: Option<&PathBuf>) -> MigraResult<Config> {
         let config_path = match config_path {
             Some(config_path) if config_path.is_dir() => {
                 Some(config_path.join(MIGRA_TOML_FILENAME))
             }
-            Some(config_path) => Some(config_path),
+            Some(config_path) => Some(config_path.clone()),
             None => recursive_find_project_root()
                 .map(|path| path.join(MIGRA_TOML_FILENAME))
                 .ok(),

migra-cli/src/main.rs

@@ -7,6 +7,7 @@ extern crate cfg_if;
 #[cfg(not(any(feature = "postgres", feature = "mysql")))]
 compile_error!(r#"Either features "postgres" or "mysql" must be enabled for "migra" crate"#);
 
+mod app;
 mod commands;
 mod config;
 mod database;
@@ -14,48 +15,13 @@ mod error;
 mod opts;
 
 use crate::error::StdResult;
+use app::App;
 use config::Config;
-use opts::{AppOpt, Command, StructOpt};
-use std::io;
+use opts::{AppOpt, StructOpt};
 
 fn main() -> StdResult<()> {
     #[cfg(feature = "dotenv")]
     dotenv::dotenv().ok();
 
-    let opt = AppOpt::from_args();
-
-    match opt.command {
-        Command::Init => {
-            commands::initialize_migra_manifest(opt.config)?;
-        }
-        Command::Apply(opts) => {
-            let config = Config::read(opt.config)?;
-            commands::apply_sql(config, opts)?;
-        }
-        Command::Make(opts) => {
-            let config = Config::read(opt.config)?;
-            commands::make_migration(config, opts)?;
-        }
-        Command::List => {
-            let config = Config::read(opt.config)?;
-            commands::print_migration_lists(config)?;
-        }
-        Command::Upgrade(opts) => {
-            let config = Config::read(opt.config)?;
-            commands::upgrade_pending_migrations(config, opts)?;
-        }
-        Command::Downgrade(opts) => {
-            let config = Config::read(opt.config)?;
-            commands::rollback_applied_migrations(config, opts)?;
-        }
-        Command::Completions(opts) => {
-            AppOpt::clap().gen_completions_to(
-                env!("CARGO_BIN_NAME"),
-                opts.into(),
-                &mut io::stdout(),
-            );
-        }
-    }
-
-    Ok(())
+    App::new(AppOpt::from_args()).run_command()
 }

migra-cli/src/opts.rs

@@ -2,17 +2,17 @@ use std::path::PathBuf;
 use structopt::clap;
 pub use structopt::StructOpt;
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 #[structopt(bin_name = "migra", name = "Migra")]
 pub(crate) struct AppOpt {
-    #[structopt(short, long)]
-    pub config: Option<PathBuf>,
+    #[structopt(name = "config", short, long)]
+    pub config_path: Option<PathBuf>,
 
     #[structopt(subcommand)]
     pub command: Command,
 }
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 pub(crate) enum Command {
     Init,
 
@@ -32,20 +32,20 @@ pub(crate) enum Command {
     Completions(CompletionsShell),
 }
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 pub(crate) struct ApplyCommandOpt {
     #[structopt(parse(from_str))]
     pub file_name: String,
 }
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 pub(crate) struct MakeCommandOpt {
     /// Name of the migration to create in specify directory.
     #[structopt(parse(from_str))]
     pub migration_name: String,
 }
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 pub(crate) struct UpgradeCommandOpt {
     /// Name of the existing migration that will update the schema
     /// in the database.
@@ -57,7 +57,7 @@ pub(crate) struct UpgradeCommandOpt {
     pub migrations_number: Option<usize>,
 }
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 pub(crate) struct DowngradeCommandOpt {
     /// How many applied migrations do we have to rollback.
     #[structopt(long = "number", short = "n", default_value = "1")]
@@ -68,7 +68,7 @@ pub(crate) struct DowngradeCommandOpt {
     pub all_migrations: bool,
 }
 
-#[derive(Debug, StructOpt)]
+#[derive(Debug, StructOpt, Clone)]
 pub(crate) enum CompletionsShell {
     Bash,
     Fish,