Added create DB function, helper functions, moved rec. perm. getter

.drone.yml

@@ -1,196 +1,28 @@
 kind: pipeline
-name: amd64 [debug]
+name: test-on-amd64
 
 platform:
   arch: amd64
 
 steps:
-- name: build [debug]
-  image: rust:1.71.1-slim-bookworm
+- name: test
+  image: rust:alpine
   commands:
   - rustc --version
   - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - cargo build --all
-
-- name: test [debug]
-  image: rust:1.71.1-slim-bookworm
-  commands:
-  - rustc --version
-  - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - cargo test --all
-
-- name: lint-clippy [debug]
-  image: rust:1.71.1-slim-bookworm
-  commands:
-  - rustc --version
-  - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - rustup component add clippy
-  - cargo clippy --all
+  - cargo test --verbose --all
 
 ---
 kind: pipeline
-name: arm64 [debug]
+name: test-on-arm64
 
 platform:
   arch: arm64
 
 steps:
-- name: build [debug]
-  image: rust:1.71.1-slim-bookworm
+- name: test
+  image: rust:alpine
   commands:
   - rustc --version
   - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - cargo build --all
-
-- name: test [debug]
-  image: rust:1.71.1-slim-bookworm
-  commands:
-  - rustc --version
-  - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - cargo test --all
-
-- name: lint-clippy [debug]
-  image: rust:1.71.1-slim-bookworm
-  commands:
-  - rustc --version
-  - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - rustup component add clippy
-  - cargo clippy --all
-
----
-kind: pipeline
-name: amd64 [release]
-
-platform:
-  arch: amd64
-
-steps:
-- name: build and test [release]
-  image: rust:1.71.1-slim-bookworm
-  commands:
-  - rustc --version
-  - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - cargo test --all --release
-
----
-kind: pipeline
-name: arm64 [release]
-
-platform:
-  arch: arm64
-
-steps:
-- name: build and test [release]
-  image: rust:1.71.1-slim-bookworm
-  commands:
-  - rustc --version
-  - cargo --version
-  # Stupid workarounds, for stupid problems
-  - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-  - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-  - cargo test --all --release
-
----
-kind: pipeline
-name: rustfmt
-steps:
-  - name: Format Project with rustfmt
-    image: rust:1.71.1-alpine
-    commands:
-      - rustc --version
-      - cargo --version
-
-      # Stupid workarounds, for stupid problems
-      - echo "nameserver 1.1.1.1" >> /etc/resolv.conf
-      - echo "nameserver 1.0.0.1" >> /etc/resolv.conf
-      - rustup component add rustfmt
-      - cargo fmt --all --check && echo "No formatting required, exiting early..." && exit 0
-      - cargo fmt --all --verbose
-      
-      # Check for format loop
-      - apk add git
-      - '[ "$(git log -1 --pretty=%B | grep -E ".+")" = "rustfmt" ] && echo "format loop detected, aborting..." && exit 1'
-
-      # Get necessary packages
-      - apk add openssh gpg gpg-agent
-
-      # configure SSH and import private key
-      - mkdir -p "$${HOME}/.ssh"
-      - echo "$SSH_PRIVATE_KEY" > "$${HOME}/.ssh/git"
-      - echo "Host git.libre.moe" >> "$${HOME}/.ssh/config"
-      - echo "	User git" >> "$${HOME}/.ssh/config"
-      - echo "	IdentityFile $${HOME}/.ssh/git" >> "$${HOME}/.ssh/config"
-      - echo "$GITEA_ED25519_SIG" >> "$${HOME}/.ssh/known_hosts"
-      - echo "$GITEA_RSA_SIG" >> "$${HOME}/.ssh/known_hosts"
-      - echo "$GITEA_ECDSA_SIG" >> "$${HOME}/.ssh/known_hosts"
-      - chmod 700 -R "$${HOME}/.ssh"
-
-      # setup gpg
-      - gpg-agent --daemon
-        # the git config gpg.program absolutely despises anything other than a path, including additional arguments.
-        # so we just put it into it's own shell script and use that later
-      - echo "#!/bin/sh" >> /tmp/gpg.sh
-      - echo gpg --batch --pinentry-mode loopback --passphrase '$GPG_PASSPHRASE' \$@ >> /tmp/gpg.sh
-      - chmod 777 /tmp/gpg.sh
-
-      # import gpg key
-      - echo "$GPG_PRIVKEY" > /tmp/private.key
-      - /tmp/gpg.sh --import /tmp/private.key >> /tmp/import.sh || exit 2
-
-      # configure git
-      - git config --local user.name "WANessa"
-      - git config --local user.email "$GIT_EMAIL_ADDRESS"
-      - git config --local user.signingkey "$GPG_PUBKEY_ID"
-      - git config --local gpg.program "/tmp/gpg.sh" # see above comment
-      # Uncomment below line for ssh debugging
-      # - git config core.sshCommand '/usr/bin/ssh -v'
-      - git remote add ssh "$DRONE_GIT_SSH_URL"
-
-      # commit and push every modified file, does not include new files, because why should it?
-      - GIT_COMMITTER_NAME="WANessa" GIT_COMMITTER_EMAIL="$GIT_EMAIL_ADDRESS" git commit --author "$DRONE_COMMIT_AUTHOR_NAME <$DRONE_COMMIT_AUTHOR_EMAIL>" -S -a -m "rustfmt"
-      - git push ssh
-
-    environment:
-      SSH_PRIVATE_KEY:
-        from_secret: WANESSA_SSH_PRIVKEY
-      GIT_EMAIL_ADDRESS:
-        from_secret: WANESSA_EMAIL_ADDRESS
-      GITEA_ED25519_SIG:
-        from_secret: GIT_ED25519_SIG
-      GITEA_RSA_SIG:
-        from_secret: GIT_RSA_SIG
-      GITEA_ECDSA_SIG:
-        from_secret: GIT_ECDSA_SIG
-      GPG_PUBKEY_ID:
-        from_secret: WANESSA_GPG_PUBKEY_ID
-      GPG_PASSPHRASE:
-        from_secret: WANESSA_GPG_PASSPHRASE
-      GPG_PRIVKEY:
-        from_secret: WANESSA_GPG_PRIVKEY
-
-depends_on:
-- amd64 [debug]
-- arm64 [debug]
-- amd64 [release]
-- arm64 [release]
+  - cargo test --verbose --all

.vscode/settings.json

@@ -0,0 +1,7 @@
+{
+    "rust-analyzer.linkedProjects": [
+        "./Cargo.toml",
+        "./Cargo.toml"
+    ],
+    "rust-analyzer.showUnlinkedFileNotification": false
+}

.vscode/tasks.json

@@ -0,0 +1,17 @@
+{
+	"version": "2.0.0",
+	"tasks": [
+		{
+			"type": "cargo",
+			"command": "build",
+			"problemMatcher": [
+				"$rustc"
+			],
+			"group": {
+				"kind": "build",
+				"isDefault": true
+			},
+			"label": "rust: cargo build"
+		}
+	]
+}

Cargo.toml

@@ -6,15 +6,4 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-
-[lints.rust]
-unsafe_code = "forbid"
-
-[lints.clippy]
-enum_glob_use = "deny" # https://rust-lang.github.io/rust-clippy/master/index.html#/enum_glob_use
-pedantic = "deny" # https://rust-lang.github.io/rust-clippy/master/index.html#/?groups=pedantic
-nursery = "deny" # wip lints: https://rust-lang.github.io/rust-clippy/master/index.html#/?groups=nursery
-unwrap_used = "deny" # https://rust-lang.github.io/rust-clippy/master/index.html#/unwrap_used
-missing_const_for_fn = "warn" # https://rust-lang.github.io/rust-clippy/master/index.html#/missing_const_for_fn
-missing_assert_message = "deny" # https://rust-lang.github.io/rust-clippy/master/index.html#/missing_assert_message
-missing_errors_doc = "deny" # https://rust-lang.github.io/rust-clippy/master/index.html#/missing_assert_message
+mysql = "*"

rustfmt.toml

@@ -1 +0,0 @@
-hard_tabs = true

src/database.rs

@@ -0,0 +1,354 @@
+//! 
+//! 
+//! The database module to use WANessa's MySQL database
+//! 
+//! This module provides abstraction for the networking and SQL queries
+//! to simplify the database access and provide structures to represent
+//! the database's content. The following functionalities are provided:
+//! - Creating a new WANessa database from scratch
+//! - Reading localized texts from the database
+//! - Getting info about permission spaces
+//! - Getting and setting info about a user's permissions in specific spaces
+//! 
+//! Note that this module is not responsible for ANY safety features. Even
+//! simple attacks like SQL injections are not checked for.
+//! DO NOT PASS ANY UNCHECKED USER INPUT TO ANY OF THESE FUNCTIONS!
+//! 
+
+use mysql::{*, prelude::{Queryable, FromRow}};
+use std::fmt;
+
+
+/// The 'TextType' enum represents the type of a LocalizedText.
+/// It is used to categorize the meaning of the text's content
+/// (is it a greeting, an affirmation, an insult, ...)
+pub enum TextType {
+
+    /// The text is some type of greeting
+    Greeting = 0,
+
+    /// The text is some kind of an affirmative statement
+    Ok = 1,
+
+    /// The text is some kind of a negative statement
+    NotOk = 2,
+
+    /// The text is a translated name for a role
+    RoleName = 3,
+}
+
+impl TextType {
+    #[allow(dead_code)]
+    pub fn fmt(&self, tt: &mut fmt::Formatter) -> fmt::Result {
+        let s: &str = match self {
+            TextType::Greeting => "Greeting",
+            TextType::Ok => "Ok",
+            TextType::NotOk => "NotOk",
+            TextType::RoleName => "RoleName"
+        };
+        
+        tt.write_str(s)?;
+
+        Ok(())
+    }
+    fn from(item: u32) -> Self {
+        match item {
+            0 => TextType::Greeting,
+            1 => TextType::Ok,
+            2 => TextType::NotOk,
+            3 => TextType::RoleName,
+            _ => panic!("Invalid value"),
+        }
+    }
+}
+
+/// A representation of a tuple stored in the 'LocalizedText' relation of the database
+pub struct LocalizedText {
+
+    /// The ID used to identify the specific text in the database. Note
+    /// that the same text translated to different languages still has
+    /// the same ID
+    pub id: usize,
+    
+    /// The language the text is translated in
+    pub language_id: usize,
+
+    /// The actual text content
+    pub content: String,
+
+    /// The type of the text
+    pub text_type: TextType
+}
+
+impl FromRow for LocalizedText {
+    fn from_row_opt(row: Row) -> std::result::Result<Self, FromRowError> {
+        let (id, language_id, content, text_type): (usize, usize, String, u32) = from_row_opt(row)?;
+        let text_type = TextType::from(text_type);
+        Ok(Self { id, language_id, content, text_type })
+    }
+}
+
+/// A representation of a tuple stored in the 'Space' relation of the database
+pub struct Space {
+    pub id: usize,
+    pub name: String,
+    pub parent_id: Option<usize>
+}
+
+impl FromRow for Space {
+    fn from_row_opt(row: Row) -> std::result::Result<Self, FromRowError> {
+        let (id, name, parent_id): (usize, String, Option<usize>) = from_row_opt(row)?;
+        Ok(Self { id, name, parent_id})
+    }
+}
+
+/// A representation of a tuple stored in the 'Role' relation of the database
+pub struct Role {
+    pub id: usize,
+    pub localized_name_id: usize,
+    pub permissions: String
+}
+
+impl FromRow for Role {
+    fn from_row_opt(row: Row) -> std::result::Result<Self, FromRowError> {
+        let (id, localized_name_id, permissions): (usize, usize, String) = from_row_opt(row)?;
+        Ok(Self { id, localized_name_id, permissions})
+    }
+}
+
+/// A representation of a tuple stored in the 'User' relation of the database
+pub struct User {
+    /// Represents the internal ID for this user
+    pub id: String,
+
+    /// Represents the display name of the user
+    pub name: String,
+}
+
+impl FromRow for User {
+    fn from_row_opt(row: Row) -> std::result::Result<Self, FromRowError> {
+        let (id, name): (String, String) = from_row_opt(row)?;
+        Ok(Self { id, name})
+    }
+}
+
+///
+/// A non-public helper function that performs a query and returns the result as an option value
+/// Note that the value enclosed in the option needs to implement FromRow.
+/// 
+fn query_and_handle_error<RetType: FromRow>(connection: &mut PooledConn, query: String) -> Option<RetType> {
+    match connection.query_first(query) {
+        Ok(opt) => {
+            match opt {
+                Some(lt) => Some(lt),
+                None => None,
+            }
+        },
+        Err(e) => {
+            println!("ERR! {}", e.to_string());
+            None
+        },
+    }
+}
+
+
+/// Initializes the database. Tries to establish a connection to the url specified
+/// and returns true if the initialization succeeded and false otherwise.
+#[allow(dead_code)]
+pub fn initialize(url: &str, port: u16, dbname: &str, username: &str, password: &str) -> Result<PooledConn, Error> {
+    let full_url: String = format!("mysql://{}:{}@{}:{}/{}", username, password, url, port, dbname);
+    let pool = Pool::new(full_url.as_str())?;
+    let conn = pool.get_conn()?;
+
+    Ok(conn)
+}
+
+/// A helper function for more readable code. Initializes the database and panics
+/// if any error occurs during the function.
+#[allow(dead_code)]
+pub fn initialize_or_panic(url: &str, port: u16, dbname: &str, username: &str, password: &str) -> PooledConn {
+    match initialize(url, port, dbname, username, password) {
+        Ok(c) => {
+            return c;
+        },
+        Err(e) => {
+            // Panic at this point as this is a critical error that doesn't allow the program
+            // to be run safely
+            panic!("Database initialization error! (\"{}\")", e.to_string());
+        }
+    }
+}
+
+/// Retrieves a LocalizedText from the database and returns an instance
+/// of Option<LocalizedText>. See LocalizedText definition for more information.
+/// 
+/// connection is the database connection returned from the initialize function.
+/// 
+/// text_id is the ID of the text as described in the "LocalizedText"
+/// documentation. This will return an empty option if no text with the ID
+/// specified is present in the database.
+/// 
+/// language_id is the target language in which the text
+/// should be returned. Note that this will fall back to any other
+/// language if the text is not present for the specified language in the
+/// database.
+#[allow(dead_code)]
+pub fn localized_text(connection: &mut PooledConn, text_id: usize, language_id: usize) -> Option<LocalizedText> {
+    let query: String = format!("SELECT * FROM LocalizedText WHERE ID={} AND LanguageID={}" , text_id, language_id);
+    return query_and_handle_error(connection, query);
+}
+
+/// Retrieves a Space from the database and returns an instance of Option<Space>, which holds a space instance
+/// if the space was found and no error occured and None otherwise.
+/// 
+/// connection is the database connection returned from the initialize function.
+/// 
+/// space_id is the ID of the space that should be retrieved from the database.
+#[allow(dead_code)]
+pub fn get_space(connection: &mut PooledConn, space_id: usize) -> Option<Space> {
+    let query: String = format!("SELECT * FROM Space WHERE ID={}" , space_id);
+    return query_and_handle_error(connection, query);
+}
+
+/// Retrieves the permission description string for the specified user from the database and returns
+/// an instance of Option<String>. Note that this function will not take into account the parent spaces
+/// (if the parent space defines "Allow" for a permission and the specified space defined "Disallow", this
+/// function will return only the space-local settings, which in this case would be "Disallow").
+/// See the get_user_permissions_recurse function to recursively get the permission string that actually
+/// determines what a user can do in the specified space.
+/// 
+/// connection is the database connection returned from the initialize function.
+/// 
+/// user_id is the ID of the user whose permissions should be returned.
+/// 
+/// space_id is the ID for the space, for that the permissions should be evaluated.
+#[allow(dead_code)]
+pub fn get_user_permissions(connection: &mut PooledConn, user_id: &str, space_id: usize) -> Option<String> {
+    let query: String = format!(
+        "SELECT Permissions FROM UserRoles JOIN Role ON UserRoles.RoleID=Role.RoleID WHERE SpaceID={} AND UserID='{}'",
+        space_id,
+        user_id);
+    return query_and_handle_error(connection, query);
+}
+
+/// Updates the permissions of a specific user in a specific space
+#[allow(dead_code)]
+pub fn set_role_permissions(connection: &mut PooledConn, role_id: usize, new_perms: &str) {
+    let query: String = format!("UPDATE Role SET Permissions='{}' WHERE RoleID={}", new_perms, role_id);
+    let _: Option<String> = query_and_handle_error(connection, query);
+}
+
+/// Returns the permissions of a specific role
+#[allow(dead_code)]
+pub fn get_role_permissions(connection: &mut PooledConn, role_id: usize) -> Option<String> {
+    let query: String = format!("SELECT Permissions FROM Role WHERE RoleID={}", role_id);
+    return query_and_handle_error(connection, query);
+}
+
+/// Returns the username for the user with the specified ID
+#[allow(dead_code)]
+pub fn get_username(connection: &mut PooledConn, user_id: String) -> Option<String> {
+    let query: String = format!("SELECT Name FROM User WHERE ID={}", user_id);
+    return query_and_handle_error(connection, query);
+}
+
+/// Creates the WANessa database from scratch.
+#[allow(dead_code)]
+pub fn create_db(connection: &mut PooledConn) {
+    // Create the LocalizedText relation
+    let _: Option<String> = query_and_handle_error(connection, String::from("CREATE TABLE LocalizedText (\
+ID INT PRIMARY KEY,\
+LanguageID INT NOT NULL,\
+Content varchar(200) NOT NULL,\
+Type INT NOT NULL CHECK (Type >= 0 AND Type <= 3))"));
+
+    // Create the Role relation
+    let _: Option<String> = query_and_handle_error(connection, String::from("CREATE TABLE Role (\
+RoleID INT PRIMARY KEY,\
+LocalizedNameID INT references LocalizedText(ID) NOT NULL,\
+Permissions varchar(60) NOT NULL"));
+
+    // Create the Space relation
+    let _: Option<String> = query_and_handle_error(connection, String::from("CREATE TABLE Space (\
+ID INT PRIMARY KEY,\
+Name varchar(80) NOT NULL,\
+ParentSpaceID INT references Space(ID))"));
+
+    // Create the User relation
+    let _: Option<String> = query_and_handle_error(connection, String::from("CREATE TABLE User (\
+ID varchar(50) PRIMARY KEY,\
+Name varchar(80) NOT NULL)"));
+
+    // Create the UserRoles relation
+    let _: Option<String> = query_and_handle_error(connection, String::from("CREATE TABLE UserRoles (\
+UserID varchar(50) references User(ID) NOT NULL,\
+SpaceID INT references Space(ID) NOT NULL,\
+RoleID INT references Role(RoleID) NOT NULL,\
+PRIMARY KEY (UserID, SpaceID, RoleID)\
+)"));
+}
+
+
+/// 
+/// The test module for the database
+/// 
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_connect_and_get_text() {
+        // Test settings
+        let url = "localhost";
+        let port = 3306;
+        let dbname = "WANessaDB";
+        let username = "testuser";
+        let password = "12345";
+
+        // Query settings
+        let text_id = 1;
+        let lang_id = 1;
+
+        // Perform test
+        let mut c = initialize_or_panic(url, port, dbname, username, password);
+
+        match localized_text(&mut c, text_id, lang_id) {
+            Some(t) => println!("Got text from database: {}", t.content),
+            None => println!("No text found for {} in lang {}!", text_id, lang_id)
+        }
+    }
+
+    #[test]
+    fn test_connect_and_get_perms() {
+        // Test settings
+        let url = "localhost";
+        let port = 3306;
+        let dbname = "WANessaDB";
+        let username = "testuser";
+        let password = "12345";
+
+        // Query settings
+        let target_user = "testuser";
+        let space_id = 1;
+
+        // Perform test
+        let mut c = initialize_or_panic(url, port, dbname, username, password);
+
+        match get_user_permissions(&mut c, target_user, space_id) {
+            Some(t) => println!("Got permissions from database: {}", t.as_str()),
+            None => println!("No permissions found for user {}!", target_user)
+        }
+    }
+
+    #[test]
+    fn test_permission_set() {
+        let mut db_conn = initialize_or_panic("localhost", 
+        3306, 
+        "WANessaDB", 
+        "testuser", 
+        "12345");
+
+        set_role_permissions(&mut db_conn, 1, "p");
+    }
+}

src/main.rs

@@ -1,3 +1,25 @@
-fn main() {
-	println!("Hello, world!");
+use mysql::PooledConn;
+
+mod database;
+mod permission;
+
+fn main()
+{
+    // Database initialization and some example code
+    let mut db_conn: PooledConn = database::initialize_or_panic(
+        "localhost", 
+        3306, 
+        "WANessaDB", 
+        "testuser", 
+        "12345");
+
+    let text = database::localized_text(&mut db_conn, 1, 1);
+    match text {
+        Some(_) => {
+            println!("Got the text!");
+        },
+        None => {
+            println!("Got no text :(");
+        }
+    }
 }

src/permission.rs

@@ -0,0 +1,223 @@
+//! 
+//! 
+//! The permission module handles everything regarding permission management.
+//! This module's tasks are:
+//! - Providing structures and enums related to permission handling to other modules
+//! - Granting / Revoking permissions from/to user(s)
+//! 
+//! 
+
+use std::{collections::HashMap, str::FromStr, hash::Hash};
+use mysql::*;
+use crate::database::*;
+use crate::database;
+
+/// This enum contains all permissions
+#[derive(PartialEq, Eq, Hash)]
+#[allow(dead_code)]
+pub enum Permission
+{
+    UseCommands = 0,
+}
+
+impl Permission {
+    #[allow(dead_code)]
+    fn is_set(self, permstring: String) -> bool {
+        match permstring.chars().nth(self as usize) {
+            Some(c) => c == 'p',
+            None => panic!("The permstring provided does not contain all permissions and is therefore invalid!")
+        }
+    }
+}
+
+/// This enum describes the state of a permission for a PermissionTable. Any Permission
+/// can be allowed, disallowed or passed through to a subsidiary PermissionTable (don't care state).
+#[allow(dead_code)]
+pub enum PermState
+{
+    Allow = 2,
+    DontCare = 1,
+    Disallow = 0
+}
+
+impl FromStr for PermState {
+    type Err = ();
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "p" => Ok(PermState::Allow),
+            "n" => Ok(PermState::Disallow),
+            "x" => Ok(PermState::DontCare),
+            _ => Err(()),
+        }
+    }
+}
+
+/// Definition of a PermissionTable. A permission table is a map
+/// that provides one of the three PermStates for every permission.
+#[allow(dead_code)]
+pub struct PermissionTable {
+    map: HashMap<Permission, PermState>
+}
+
+impl PermissionTable {
+    fn new() -> Self {
+        PermissionTable { map: HashMap::new() }
+    }
+    fn insert(&mut self, perm: Permission, state: PermState) {
+        self.map.insert(perm, state);
+    }
+    fn from_str(s: &str) -> Result<Self, ()> {
+        let mut table = PermissionTable::new();
+        for (i, state) in s.chars().enumerate() {
+            if let Ok(state) = PermState::from_str(&state.to_string()) {
+                let permission = match i {
+                    0 => Permission::UseCommands,
+                    _ => return Err(()),
+                };
+                table.insert(permission, state);
+            } else {
+                return Err(());
+            }
+        }
+        Ok(table)
+    }
+    fn get_permstring(self) -> &'static str {
+        return ""
+    }
+}
+
+/// Sets the state of the specified Permission for the specified role to the specified state.
+#[allow(dead_code)]
+pub fn set_permission(db_connection: &mut PooledConn, role_id: usize, perm: Permission, state: PermState) -> bool {
+    match database::get_role_permissions(db_connection, role_id) {
+        Some(permstring) => {
+            match PermissionTable::from_str(permstring.as_str()) {
+                Ok(mut permtable) => {
+                    permtable.insert(perm, state);
+                    database::set_role_permissions(db_connection, role_id, permtable.get_permstring());
+                    return true;
+                },
+                Err(_) => return false
+            }
+        },
+        None => return false
+    }
+}
+
+/// Retrieves the actual permissions of a user from the database. This function also applies all the parent space's rules,
+/// so that the result of this function can be used to determine, if a user has a specific permission in a specific space.
+/// This function returns an Option, which will be empty if an error occured (e.g. database inconsistency). If no error
+/// occurs, the Option will contain a String that only contains 'p' for positive permissions and 'n' for negative ones.
+/// Permissions that are globally defined as "Don't care" will be treated as "Disallow" by this function.
+#[allow(dead_code)]
+pub fn get_permissions(db_connection: &mut PooledConn, user_id: &str, space_id: usize) -> Option<String> {
+    let mut permstr_opt: Option<String> = get_user_permissions(db_connection, user_id, space_id);
+    let space_opt: Option<Space> = get_space(db_connection, space_id);
+
+    match permstr_opt {
+        Some(mut permstr) => {
+            let mut space: Space = match space_opt {
+                Some(s) => s,
+                None => return None // The initial space could not be retrieved from the database
+            };
+            
+            loop {
+                // query the current space in order to get the parent space ID
+                let parent_id: usize;
+                space = match space.parent_id {
+                    Some(parent_space_id) => {
+                        parent_id = parent_space_id;
+                        match get_space(db_connection, parent_space_id) {
+                            Some(parent_space) => parent_space,
+                            None => return None // The parent space specified in the database could not be retrieved
+                        }
+                    },
+                    None => break // The top of the space hierarchy has been reached. The permission string is complete.
+                };
+
+                permstr_opt = get_user_permissions(db_connection, user_id, parent_id);
+                permstr = match permstr_opt {
+                    Some(n) => {
+                        // Here we have the permission string from the sub-space ('permstr') and the permission string from the
+                        // super-space ('n'). Now the sub-space string will be overridden by every non-dont-care state in the
+                        // super-space string, because super-space rules are always prioritized higher than the sub-space rules.
+                        let mut newpermstr = String::from("");
+                        
+                        if n.len() != permstr.len() {
+                            return None; // There is a database inconsistency where not all permstrings are equally long.
+                        }
+                        for (super_char, sub_char) in n.chars().zip(permstr.chars()) {
+                            match super_char {
+                                'p' => newpermstr += "p",
+                                'n' => newpermstr += "n",
+                                'x' => newpermstr += sub_char.to_string().as_str(),
+                                _ => return None // There is a database inconsistency where not all permstrings consist of 'p', 'n' or 'x'.
+                            }
+                        }
+
+                        newpermstr
+                    },
+                    None => {
+                        // No explicit entry for the permissions at that level exist. This is valid and every permission entry
+                        // is therefore assumed as "Don't care". Because a string consisting of just "Don't care" states will not
+                        // change the permissions in the sub-space, the permstr will stay the same in this case.
+                        permstr
+                    } 
+                };
+            };
+
+            // Check the characters for validity due to the top-most layer not being checked in the loop
+            for c in permstr.chars() {
+                if c != 'p' && c != 'x' && c != 'n' {
+                    return None // The permission string in the top-most layer contains invalid states
+                }
+            }
+
+            // At this point, permstr contains all the permissions of the user while only considering the database entries. However,
+            // some permissions could be declared as "Don't care" on every level. These "Don't care" states will now be replaced by
+            // "Disallow" states.
+            permstr = permstr.chars().map(|c| if c == 'x' { 'n' } else { c }).collect();
+
+            Some(permstr)
+        },
+        None => None // The permission query for the user in the space failed
+    }
+}
+
+/// Checks if the user has the specified permission in the specified space
+#[allow(dead_code)]
+pub fn has_permission(db_connection: &mut PooledConn, user_id: &str, space_id: usize, perm: Permission) -> Option<bool>  {
+    let perms = get_permissions(db_connection, user_id, space_id);
+    match perms {
+        Some(permstring) => Some(perm.is_set(permstring)),
+        None => None
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use crate::database;
+    use super::*;
+
+    #[test]
+    fn test_permission_check() {
+        let mut db_conn = database::initialize_or_panic("localhost", 
+        3306, 
+        "WANessaDB", 
+        "testuser", 
+        "12345");
+
+        let hasperm = has_permission(&mut db_conn, "testuser", 0, Permission::UseCommands);
+        match hasperm {
+            Some(hasres) => {
+                match hasres {
+                    true => println!("The user has the specified permission"),
+                    false => println!("The user does not have the specified permission")
+                }
+            },
+            None => panic!("An error occured. has_permission returned no value.")
+        }
+    }
+}