feat: implement user follow/unfollow functionality and thought retrieval by user

- Added follow and unfollow endpoints for users.
- Implemented logic to retrieve thoughts by a specific user.
- Updated user error handling to include cases for already following and not following.
- Created persistence layer for follow relationships.
- Enhanced user and thought schemas to support new features.
- Added tests for follow/unfollow endpoints and thought retrieval.
- Updated frontend to display thoughts and allow posting new thoughts.

thoughts-backend/Cargo.lock

@@ -642,6 +642,7 @@ name = "common"
 version = "0.1.0"
 dependencies = [
  "sea-orm",
+ "sea-query",
  "serde",
  "utoipa",
 ]

thoughts-backend/Cargo.toml

@@ -17,6 +17,7 @@ members = ["api", "app", "doc", "models", "migration", "utils"]
 axum = { version = "0.8.4", default-features = false }
 tower = { version = "0.5.2", default-features = false }
 sea-orm = { version = "1.1.12" }
+sea-query = { version = "0.32.6" }                              # Added sea-query dependency
 serde = { version = "1.0.219", features = ["derive"] }
 serde_json = { version = "1.0.140" }
 tracing = "0.1.41"

thoughts-backend/api/src/error/adapter.rs

@@ -27,6 +27,11 @@ impl HTTPError for UserError {
     fn to_status_code(&self) -> StatusCode {
         match self {
             UserError::NotFound => StatusCode::NOT_FOUND,
+            UserError::NotFollowing => StatusCode::BAD_REQUEST,
+            UserError::Forbidden => StatusCode::FORBIDDEN,
+            UserError::UsernameTaken => StatusCode::BAD_REQUEST,
+            UserError::AlreadyFollowing => StatusCode::BAD_REQUEST,
+            UserError::Internal(_) => StatusCode::INTERNAL_SERVER_ERROR,
         }
     }
 }

thoughts-backend/api/src/extractor/auth.rs

@@ -0,0 +1,29 @@
+use axum::{
+    extract::FromRequestParts,
+    http::{request::Parts, StatusCode},
+};
+
+use app::state::AppState;
+
+// A dummy struct to represent an authenticated user.
+// In a real app, this would contain user details from a validated JWT.
+pub struct AuthUser {
+    pub id: i32,
+}
+
+impl FromRequestParts<AppState> for AuthUser {
+    type Rejection = (StatusCode, &'static str);
+
+    async fn from_request_parts(
+        _parts: &mut Parts,
+        _state: &AppState,
+    ) -> Result<Self, Self::Rejection> {
+        // For now, we'll just return a hardcoded user.
+        // In a real implementation, you would:
+        // 1. Extract the `Authorization: Bearer <token>` header.
+        // 2. Validate the JWT.
+        // 3. Extract the user ID from the token claims.
+        // 4. Return an error if the token is invalid or missing.
+        Ok(AuthUser { id: 1 }) // Assume user with ID 1 is always authenticated.
+    }
+}

thoughts-backend/api/src/extractor/mod.rs

@@ -1,5 +1,7 @@
+mod auth;
 mod json;
 mod valid;
 
+pub use auth::AuthUser;
 pub use json::Json;
 pub use valid::Valid;

thoughts-backend/api/src/routers/feed.rs

@@ -0,0 +1,39 @@
+use axum::{extract::State, response::IntoResponse, routing::get, Json, Router};
+
+use app::{
+    persistence::{follow::get_followed_ids, thought::get_feed_for_user},
+    state::AppState,
+};
+use models::schemas::thought::{ThoughtListSchema, ThoughtSchema};
+
+use crate::{error::ApiError, extractor::AuthUser};
+
+#[utoipa::path(
+    get,
+    path = "/feed",
+    responses(
+        (status = 200, description = "Authenticated user's feed", body = ThoughtListSchema)
+    ),
+    security(
+        ("api_key" = []),
+        ("bearer_auth" = [])
+    )
+)]
+async fn feed_get(
+    State(state): State<AppState>,
+    auth_user: AuthUser,
+) -> Result<impl IntoResponse, ApiError> {
+    let followed_ids = get_followed_ids(&state.conn, auth_user.id).await?;
+    let thoughts_with_authors = get_feed_for_user(&state.conn, followed_ids).await?;
+
+    let thoughts_schema: Vec<ThoughtSchema> = thoughts_with_authors
+        .into_iter()
+        .map(ThoughtSchema::from)
+        .collect();
+
+    Ok(Json(ThoughtListSchema::from(thoughts_schema)))
+}
+
+pub fn create_feed_router() -> Router<AppState> {
+    Router::new().route("/", get(feed_get))
+}

thoughts-backend/api/src/routers/mod.rs

@@ -1,15 +1,21 @@
 use axum::Router;
 
+pub mod feed;
 pub mod root;
+pub mod thought;
 pub mod user;
 
 use app::state::AppState;
 use root::create_root_router;
 use user::create_user_router;
 
+use crate::routers::{feed::create_feed_router, thought::create_thought_router};
+
 pub fn create_router(state: AppState) -> Router {
     Router::new()
         .merge(create_root_router())
         .nest("/users", create_user_router())
+        .nest("/thoughts", create_thought_router())
+        .nest("/feed", create_feed_router())
         .with_state(state)
 }

thoughts-backend/api/src/routers/thought.rs

@@ -0,0 +1,87 @@
+use axum::{
+    extract::{Path, State},
+    http::StatusCode,
+    response::IntoResponse,
+    routing::{delete, post},
+    Router,
+};
+
+use app::{
+    error::UserError,
+    persistence::thought::{create_thought, delete_thought, get_thought},
+    state::AppState,
+};
+use models::{params::thought::CreateThoughtParams, schemas::thought::ThoughtSchema};
+
+use crate::{
+    error::ApiError,
+    extractor::{AuthUser, Json, Valid},
+    models::{ApiErrorResponse, ParamsErrorResponse},
+};
+
+#[utoipa::path(
+    post,
+    path = "/thoughts",
+    request_body = CreateThoughtParams,
+    responses(
+        (status = 201, description = "Thought created", body = ThoughtSchema),
+        (status = 400, description = "Bad request", body = ApiErrorResponse),
+        (status = 422, description = "Validation error", body = ParamsErrorResponse)
+    ),
+    security(
+        ("api_key" = []),
+        ("bearer_auth" = [])
+    )
+)]
+async fn thoughts_post(
+    State(state): State<AppState>,
+    auth_user: AuthUser,
+    Valid(Json(params)): Valid<Json<CreateThoughtParams>>,
+) -> Result<impl IntoResponse, ApiError> {
+    let thought = create_thought(&state.conn, auth_user.id, params).await?;
+    let author = app::persistence::user::get_user(&state.conn, auth_user.id)
+        .await?
+        .ok_or(UserError::NotFound)?; // Should not happen if auth is valid
+
+    let schema = ThoughtSchema::from_models(&thought, &author);
+    Ok((StatusCode::CREATED, Json(schema)))
+}
+
+#[utoipa::path(
+    delete,
+    path = "/thoughts/{id}",
+    params(
+        ("id" = i32, Path, description = "Thought ID")
+    ),
+    responses(
+        (status = 204, description = "Thought deleted"),
+        (status = 403, description = "Forbidden", body = ApiErrorResponse),
+        (status = 404, description = "Not Found", body = ApiErrorResponse)
+    ),
+    security(
+        ("api_key" = []),
+        ("bearer_auth" = [])
+    )
+)]
+async fn thoughts_delete(
+    State(state): State<AppState>,
+    auth_user: AuthUser,
+    Path(id): Path<i32>,
+) -> Result<impl IntoResponse, ApiError> {
+    let thought = get_thought(&state.conn, id)
+        .await?
+        .ok_or(UserError::NotFound)?;
+
+    if thought.author_id != auth_user.id {
+        return Err(UserError::Forbidden.into());
+    }
+
+    delete_thought(&state.conn, id).await?;
+    Ok(StatusCode::NO_CONTENT)
+}
+
+pub fn create_thought_router() -> Router<AppState> {
+    Router::new()
+        .route("/", post(thoughts_post))
+        .route("/{id}", delete(thoughts_delete))
+}

thoughts-backend/api/src/routers/user.rs

@@ -5,18 +5,22 @@ use axum::{
     routing::{get, post},
     Router,
 };
-use sea_orm::TryIntoModel;
+use sea_orm::{DbErr, TryIntoModel};
 
-use app::error::UserError;
-use app::persistence::user::{create_user, get_user, search_users};
+use app::persistence::{
+    follow,
+    thought::get_thoughts_by_user,
+    user::{create_user, get_user, search_users},
+};
 use app::state::AppState;
-use models::params::user::CreateUserParams;
-use models::queries::user::UserQuery;
+use app::{error::UserError, persistence::user::get_user_by_username};
 use models::schemas::user::{UserListSchema, UserSchema};
+use models::{params::user::CreateUserParams, schemas::thought::ThoughtListSchema};
+use models::{queries::user::UserQuery, schemas::thought::ThoughtSchema};
 
-use crate::error::ApiError;
 use crate::extractor::{Json, Valid};
 use crate::models::{ApiErrorResponse, ParamsErrorResponse};
+use crate::{error::ApiError, extractor::AuthUser};
 
 #[utoipa::path(
     post,
@@ -25,6 +29,7 @@ use crate::models::{ApiErrorResponse, ParamsErrorResponse};
     responses(
         (status = 201, description = "User created", body = UserSchema),
         (status = 400, description = "Bad request", body = ApiErrorResponse),
+        (status = 409, description = "Username already exists", body = ApiErrorResponse),
         (status = 422, description = "Validation error", body = ParamsErrorResponse),
         (status = 500, description = "Internal server error", body = ApiErrorResponse),
     )
@@ -86,8 +91,104 @@ async fn users_id_get(
         .ok_or_else(|| UserError::NotFound.into())
 }
 
+#[utoipa::path(
+    get,
+    path = "/{username}/thoughts",
+    params(
+        ("username" = String, Path, description = "Username")
+    ),
+    responses(
+        (status = 200, description = "List of user's thoughts", body = ThoughtListSchema),
+        (status = 404, description = "User not found", body = ApiErrorResponse)
+    )
+)]
+async fn user_thoughts_get(
+    State(state): State<AppState>,
+    Path(username): Path<String>,
+) -> Result<impl IntoResponse, ApiError> {
+    let user = get_user_by_username(&state.conn, &username)
+        .await?
+        .ok_or(UserError::NotFound)?;
+
+    let thoughts_with_authors = get_thoughts_by_user(&state.conn, user.id).await?;
+    let thoughts_schema: Vec<ThoughtSchema> = thoughts_with_authors
+        .into_iter()
+        .map(ThoughtSchema::from)
+        .collect();
+
+    Ok(Json(ThoughtListSchema::from(thoughts_schema)))
+}
+
+#[utoipa::path(
+    post,
+    path = "/{username}/follow",
+    params(
+        ("username" = String, Path, description = "Username to follow")
+    ),
+    responses(
+        (status = 204, description = "User followed successfully"),
+        (status = 404, description = "User not found", body = ApiErrorResponse),
+        (status = 409, description = "Already following", body = ApiErrorResponse)
+    ),
+    security(
+        ("api_key" = []),
+        ("bearer_auth" = [])
+    )
+)]
+async fn user_follow_post(
+    State(state): State<AppState>,
+    auth_user: AuthUser,
+    Path(username): Path<String>,
+) -> Result<impl IntoResponse, ApiError> {
+    let user_to_follow = get_user_by_username(&state.conn, &username)
+        .await?
+        .ok_or(UserError::NotFound)?;
+
+    let result = follow::follow_user(&state.conn, auth_user.id, user_to_follow.id).await;
+
+    match result {
+        Ok(_) => Ok(StatusCode::NO_CONTENT),
+        Err(DbErr::UnpackInsertId) => Err(UserError::AlreadyFollowing.into()),
+        Err(e) => Err(e.into()),
+    }
+}
+
+#[utoipa::path(
+    delete,
+    path = "/{username}/follow",
+    params(
+        ("username" = String, Path, description = "Username to unfollow")
+    ),
+    responses(
+        (status = 204, description = "User unfollowed successfully"),
+        (status = 404, description = "User not found or not being followed", body = ApiErrorResponse)
+    ),
+    security(
+        ("api_key" = []),
+        ("bearer_auth" = [])
+    )
+)]
+async fn user_follow_delete(
+    State(state): State<AppState>,
+    auth_user: AuthUser,
+    Path(username): Path<String>,
+) -> Result<impl IntoResponse, ApiError> {
+    let user_to_unfollow = get_user_by_username(&state.conn, &username)
+        .await?
+        .ok_or(UserError::NotFound)?;
+
+    follow::unfollow_user(&state.conn, auth_user.id, user_to_unfollow.id).await?;
+
+    Ok(StatusCode::NO_CONTENT)
+}
+
 pub fn create_user_router() -> Router<AppState> {
     Router::new()
         .route("/", post(users_post).get(users_get))
         .route("/{id}", get(users_id_get))
+        .route("/{username}/thoughts", get(user_thoughts_get))
+        .route(
+            "/{username}/follow",
+            post(user_follow_post).delete(user_follow_delete),
+        )
 }

thoughts-backend/app/src/error/user.rs

@@ -1,12 +1,22 @@
 #[derive(Debug)]
 pub enum UserError {
     NotFound,
+    NotFollowing,
+    Forbidden,
+    UsernameTaken,
+    AlreadyFollowing,
+    Internal(String),
 }
 
 impl std::fmt::Display for UserError {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             UserError::NotFound => write!(f, "User not found"),
+            UserError::NotFollowing => write!(f, "You are not following this user"),
+            UserError::Forbidden => write!(f, "You do not have permission to perform this action"),
+            UserError::UsernameTaken => write!(f, "Username is already taken"),
+            UserError::AlreadyFollowing => write!(f, "You are already following this user"),
+            UserError::Internal(msg) => write!(f, "Internal server error: {}", msg),
         }
     }
 }

thoughts-backend/app/src/persistence/follow.rs

@@ -0,0 +1,46 @@
+use sea_orm::{ActiveModelTrait, ColumnTrait, DbConn, DbErr, EntityTrait, QueryFilter, Set};
+
+use crate::error::UserError;
+use models::domains::follow;
+
+pub async fn follow_user(db: &DbConn, follower_id: i32, followee_id: i32) -> Result<(), DbErr> {
+    if follower_id == followee_id {
+        return Err(DbErr::Custom("Users cannot follow themselves".to_string()));
+    }
+
+    let follow = follow::ActiveModel {
+        follower_id: Set(follower_id),
+        followed_id: Set(followee_id),
+    };
+
+    follow.save(db).await?;
+    Ok(())
+}
+
+pub async fn unfollow_user(
+    db: &DbConn,
+    follower_id: i32,
+    followee_id: i32,
+) -> Result<(), UserError> {
+    let deleted_result = follow::Entity::delete_many()
+        .filter(follow::Column::FollowerId.eq(follower_id))
+        .filter(follow::Column::FollowedId.eq(followee_id))
+        .exec(db)
+        .await
+        .map_err(|e| UserError::Internal(e.to_string()))?;
+
+    if deleted_result.rows_affected == 0 {
+        return Err(UserError::NotFollowing);
+    }
+
+    Ok(())
+}
+
+pub async fn get_followed_ids(db: &DbConn, user_id: i32) -> Result<Vec<i32>, DbErr> {
+    let followed_users = follow::Entity::find()
+        .filter(follow::Column::FollowerId.eq(user_id))
+        .all(db)
+        .await?;
+
+    Ok(followed_users.into_iter().map(|f| f.followed_id).collect())
+}

thoughts-backend/app/src/persistence/mod.rs

@@ -1 +1,3 @@
+pub mod follow;
+pub mod thought;
 pub mod user;

thoughts-backend/app/src/persistence/thought.rs

@@ -0,0 +1,67 @@
+use sea_orm::{
+    ActiveModelTrait, ColumnTrait, DbConn, DbErr, EntityTrait, JoinType, QueryFilter, QueryOrder,
+    QuerySelect, RelationTrait, Set,
+};
+
+use models::{
+    domains::{thought, user},
+    params::thought::CreateThoughtParams,
+    schemas::thought::ThoughtWithAuthor,
+};
+
+use crate::error::UserError;
+
+pub async fn create_thought(
+    db: &DbConn,
+    author_id: i32,
+    params: CreateThoughtParams,
+) -> Result<thought::Model, DbErr> {
+    thought::ActiveModel {
+        author_id: Set(author_id),
+        content: Set(params.content),
+        ..Default::default()
+    }
+    .insert(db)
+    .await
+}
+
+pub async fn get_thought(db: &DbConn, thought_id: i32) -> Result<Option<thought::Model>, DbErr> {
+    thought::Entity::find_by_id(thought_id).one(db).await
+}
+
+pub async fn delete_thought(db: &DbConn, thought_id: i32) -> Result<(), DbErr> {
+    thought::Entity::delete_by_id(thought_id).exec(db).await?;
+    Ok(())
+}
+
+pub async fn get_thoughts_by_user(
+    db: &DbConn,
+    user_id: i32,
+) -> Result<Vec<ThoughtWithAuthor>, DbErr> {
+    thought::Entity::find()
+        .column_as(user::Column::Username, "author_username")
+        .join(JoinType::InnerJoin, thought::Relation::User.def().rev())
+        .filter(thought::Column::AuthorId.eq(user_id))
+        .order_by_desc(thought::Column::CreatedAt)
+        .into_model::<ThoughtWithAuthor>()
+        .all(db)
+        .await
+}
+
+pub async fn get_feed_for_user(
+    db: &DbConn,
+    followed_ids: Vec<i32>,
+) -> Result<Vec<ThoughtWithAuthor>, UserError> {
+    if followed_ids.is_empty() {
+        return Ok(vec![]);
+    }
+    thought::Entity::find()
+        .column_as(user::Column::Username, "author_username")
+        .join(JoinType::InnerJoin, thought::Relation::User.def().rev())
+        .filter(thought::Column::AuthorId.is_in(followed_ids))
+        .order_by_desc(thought::Column::CreatedAt)
+        .into_model::<ThoughtWithAuthor>()
+        .all(db)
+        .await
+        .map_err(|e| UserError::Internal(e.to_string()))
+}

thoughts-backend/app/src/persistence/user.rs

@@ -26,3 +26,13 @@ pub async fn search_users(db: &DbConn, query: UserQuery) -> Result<Vec<user::Mod
 pub async fn get_user(db: &DbConn, id: i32) -> Result<Option<user::Model>, DbErr> {
     user::Entity::find_by_id(id).one(db).await
 }
+
+pub async fn get_user_by_username(
+    db: &DbConn,
+    username: &str,
+) -> Result<Option<user::Model>, DbErr> {
+    user::Entity::find()
+        .filter(user::Column::Username.eq(username))
+        .one(db)
+        .await
+}

thoughts-backend/common/Cargo.toml

@@ -7,3 +7,4 @@ edition = "2021"
 serde = { workspace = true }
 utoipa = { workspace = true }
 sea-orm = { workspace = true }
+sea-query = { workspace = true }

thoughts-backend/common/src/lib.rs

@@ -1,10 +1,12 @@
 use sea_orm::prelude::DateTimeWithTimeZone;
+use sea_orm::TryGetError;
+use sea_orm::{sea_query::ColumnType, sea_query::Value, sea_query::ValueType, TryGetable};
+use sea_query::ValueTypeErr;
 use serde::Serialize;
 use utoipa::ToSchema;
 
-// Wrapper type for DateTimeWithTimeZone
 #[derive(Serialize, ToSchema)]
-#[schema(example = "2025-09-05T12:34:56Z")] // Example for OpenAPI
+#[schema(example = "2025-09-05T12:34:56Z")]
 pub struct DateTimeWithTimeZoneWrapper(String);
 
 impl From<DateTimeWithTimeZone> for DateTimeWithTimeZoneWrapper {
@@ -12,3 +14,40 @@ impl From<DateTimeWithTimeZone> for DateTimeWithTimeZoneWrapper {
         DateTimeWithTimeZoneWrapper(value.to_rfc3339())
     }
 }
+
+impl TryGetable for DateTimeWithTimeZoneWrapper {
+    fn try_get_by<I: sea_orm::ColIdx>(
+        res: &sea_orm::QueryResult,
+        index: I,
+    ) -> Result<Self, TryGetError> {
+        let value: String = res.try_get_by(index)?;
+        Ok(DateTimeWithTimeZoneWrapper(value))
+    }
+
+    fn try_get(res: &sea_orm::QueryResult, pre: &str, col: &str) -> Result<Self, TryGetError> {
+        let value: String = res.try_get(pre, col)?;
+        Ok(DateTimeWithTimeZoneWrapper(value))
+    }
+}
+
+impl ValueType for DateTimeWithTimeZoneWrapper {
+    fn try_from(v: Value) -> Result<Self, ValueTypeErr> {
+        if let Value::String(Some(string)) = v {
+            Ok(DateTimeWithTimeZoneWrapper(*string))
+        } else {
+            Err(ValueTypeErr)
+        }
+    }
+
+    fn array_type() -> sea_query::ArrayType {
+        sea_query::ArrayType::String
+    }
+
+    fn column_type() -> ColumnType {
+        ColumnType::String(sea_query::StringLen::Max)
+    }
+
+    fn type_name() -> String {
+        "DateTimeWithTimeZoneWrapper".to_string()
+    }
+}

thoughts-backend/doc/src/feed.rs

@@ -0,0 +1,10 @@
+use api::{models::ApiErrorResponse, routers::feed::*};
+use models::schemas::thought::{ThoughtListSchema, ThoughtSchema};
+use utoipa::OpenApi;
+
+#[derive(OpenApi)]
+#[openapi(
+    paths(feed_get),
+    components(schemas(ThoughtSchema, ThoughtListSchema, ApiErrorResponse))
+)]
+pub(super) struct FeedApi;

thoughts-backend/doc/src/lib.rs

@@ -3,7 +3,9 @@ use utoipa::OpenApi;
 use utoipa_scalar::{Scalar, Servable as ScalarServable};
 use utoipa_swagger_ui::SwaggerUi;
 
+mod feed;
 mod root;
+mod thought;
 mod user;
 
 #[derive(OpenApi)]
@@ -11,11 +13,15 @@ mod user;
     nest(
         (path = "/", api = root::RootApi),
         (path = "/users", api = user::UserApi),
+        (path = "/thoughts", api = thought::ThoughtApi),
+        (path = "/feed", api = feed::FeedApi),
     ),
     tags(
         (name = "root", description = "Root API"),
-        (name = "user", description = "User API"),
-    )
+        (name = "user", description = "User & Social API"),
+        (name = "thought", description = "Thoughts API"),
+        (name = "feed", description = "Feed API"),
+    ),
 )]
 struct _ApiDoc;
 

thoughts-backend/doc/src/thought.rs

@@ -0,0 +1,18 @@
+use api::{
+    models::{ApiErrorResponse, ParamsErrorResponse},
+    routers::thought::*,
+};
+use models::{params::thought::CreateThoughtParams, schemas::thought::ThoughtSchema};
+use utoipa::OpenApi;
+
+#[derive(OpenApi)]
+#[openapi(
+    paths(thoughts_post, thoughts_delete),
+    components(schemas(
+        CreateThoughtParams,
+        ThoughtSchema,
+        ApiErrorResponse,
+        ParamsErrorResponse
+    ))
+)]
+pub(super) struct ThoughtApi;

thoughts-backend/doc/src/user.rs

@@ -1,18 +1,29 @@
 use utoipa::OpenApi;
 
-use models::params::user::CreateUserParams;
-use models::schemas::user::{UserListSchema, UserSchema};
-
 use api::models::{ApiErrorResponse, ParamsErrorResponse};
 use api::routers::user::*;
+use models::params::user::CreateUserParams;
+use models::schemas::{
+    thought::{ThoughtListSchema, ThoughtSchema},
+    user::{UserListSchema, UserSchema},
+};
 
 #[derive(OpenApi)]
 #[openapi(
-    paths(users_get, users_id_get, users_post),
+    paths(
+        users_get,
+        users_id_get,
+        users_post,
+        user_thoughts_get,
+        user_follow_post,
+        user_follow_delete
+    ),
     components(schemas(
         CreateUserParams,
         UserListSchema,
         UserSchema,
+        ThoughtSchema,
+        ThoughtListSchema,
         ApiErrorResponse,
         ParamsErrorResponse,
     ))

thoughts-backend/models/src/params/thought.rs

@@ -4,8 +4,10 @@ use validator::Validate;
 
 #[derive(Deserialize, Validate, ToSchema)]
 pub struct CreateThoughtParams {
-    pub author_id: i32,
-
-    #[validate(length(min = 1, max = 128))]
+    #[validate(length(
+        min = 1,
+        max = 128,
+        message = "Content must be between 1 and 128 characters"
+    ))]
     pub content: String,
 }

thoughts-backend/models/src/schemas/thought.rs

@@ -1,23 +1,26 @@
-use crate::domains::thought;
+use crate::domains::{thought, user};
 use common::DateTimeWithTimeZoneWrapper;
+use sea_orm::FromQueryResult;
 use serde::Serialize;
 use utoipa::ToSchema;
 
-#[derive(Serialize, ToSchema)]
+#[derive(Serialize, ToSchema, FromQueryResult)]
 pub struct ThoughtSchema {
     pub id: i32,
-    pub author_id: i32,
+    #[schema(example = "frutiger")]
+    pub author_username: String,
+    #[schema(example = "This is my first thought! #welcome")]
     pub content: String,
     pub created_at: DateTimeWithTimeZoneWrapper,
 }
 
-impl From<thought::Model> for ThoughtSchema {
-    fn from(model: thought::Model) -> Self {
+impl ThoughtSchema {
+    pub fn from_models(thought: &thought::Model, author: &user::Model) -> Self {
         Self {
-            id: model.id,
-            author_id: model.author_id,
-            content: model.content,
-            created_at: model.created_at.into(),
+            id: thought.id,
+            author_username: author.username.clone(),
+            content: thought.content.clone(),
+            created_at: thought.created_at.into(),
         }
     }
 }
@@ -27,10 +30,28 @@ pub struct ThoughtListSchema {
     pub thoughts: Vec<ThoughtSchema>,
 }
 
-impl From<Vec<thought::Model>> for ThoughtListSchema {
-    fn from(models: Vec<thought::Model>) -> Self {
+impl From<Vec<ThoughtSchema>> for ThoughtListSchema {
+    fn from(thoughts: Vec<ThoughtSchema>) -> Self {
+        Self { thoughts }
+    }
+}
+
+#[derive(Debug, FromQueryResult)]
+pub struct ThoughtWithAuthor {
+    pub id: i32,
+    pub content: String,
+    pub created_at: sea_orm::prelude::DateTimeWithTimeZone,
+    pub author_id: i32,
+    pub author_username: String,
+}
+
+impl From<ThoughtWithAuthor> for ThoughtSchema {
+    fn from(model: ThoughtWithAuthor) -> Self {
         Self {
-            thoughts: models.into_iter().map(ThoughtSchema::from).collect(),
+            id: model.id,
+            author_username: model.author_username,
+            content: model.content,
+            created_at: model.created_at.into(),
         }
     }
 }

thoughts-backend/models/src/schemas/user.rs

@@ -5,14 +5,14 @@ use crate::domains::user;
 
 #[derive(Serialize, ToSchema)]
 pub struct UserSchema {
-    pub id: u32,
+    pub id: i32,
     pub username: String,
 }
 
 impl From<user::Model> for UserSchema {
     fn from(user: user::Model) -> Self {
         Self {
-            id: user.id as u32,
+            id: user.id,
             username: user.username,
         }
     }

thoughts-backend/tests/api/feed.rs

@@ -0,0 +1,63 @@
+use super::main::{create_test_user, setup};
+use axum::http::StatusCode;
+use http_body_util::BodyExt;
+use serde_json::json;
+use utils::testing::{make_get_request, make_post_request};
+
+#[tokio::test]
+async fn test_feed_and_user_thoughts() {
+    let app = setup().await;
+    create_test_user(&app.db, "user1").await; // AuthUser is ID 1
+    create_test_user(&app.db, "user2").await;
+    create_test_user(&app.db, "user3").await;
+
+    // As user1, post a thought
+    let body = json!({ "content": "A thought from user1" }).to_string();
+    make_post_request(app.router.clone(), "/thoughts", body).await;
+
+    // As a different "user", create thoughts for user2 and user3 (we cheat here since auth is hardcoded)
+    app::persistence::thought::create_thought(
+        &app.db,
+        2,
+        models::params::thought::CreateThoughtParams {
+            content: "user2 was here".to_string(),
+        },
+    )
+    .await
+    .unwrap();
+    app::persistence::thought::create_thought(
+        &app.db,
+        3,
+        models::params::thought::CreateThoughtParams {
+            content: "user3 checking in".to_string(),
+        },
+    )
+    .await
+    .unwrap();
+
+    // 1. Get thoughts for user2 - should only see their thought
+    let response = make_get_request(app.router.clone(), "/users/user2/thoughts").await;
+    assert_eq!(response.status(), StatusCode::OK);
+    let body = response.into_body().collect().await.unwrap().to_bytes();
+    let v: serde_json::Value = serde_json::from_slice(&body).unwrap();
+    assert_eq!(v["thoughts"].as_array().unwrap().len(), 1);
+    assert_eq!(v["thoughts"][0]["content"], "user2 was here");
+
+    // 2. user1's feed is initially empty
+    let response = make_get_request(app.router.clone(), "/feed").await;
+    assert_eq!(response.status(), StatusCode::OK);
+    let body = response.into_body().collect().await.unwrap().to_bytes();
+    let v: serde_json::Value = serde_json::from_slice(&body).unwrap();
+    assert!(v["thoughts"].as_array().unwrap().is_empty());
+
+    // 3. user1 follows user2
+    make_post_request(app.router.clone(), "/users/user2/follow", "".to_string()).await;
+
+    // 4. user1's feed now has user2's thought
+    let response = make_get_request(app.router.clone(), "/feed").await;
+    assert_eq!(response.status(), StatusCode::OK);
+    let body = response.into_body().collect().await.unwrap().to_bytes();
+    let v: serde_json::Value = serde_json::from_slice(&body).unwrap();
+    assert_eq!(v["thoughts"].as_array().unwrap().len(), 1);
+    assert_eq!(v["thoughts"][0]["author_username"], "user2");
+}

thoughts-backend/tests/api/follow.rs

@@ -0,0 +1,33 @@
+use super::main::{create_test_user, setup};
+use axum::http::StatusCode;
+use utils::testing::{make_delete_request, make_post_request};
+
+#[tokio::test]
+async fn test_follow_endpoints() {
+    let app = setup().await;
+    create_test_user(&app.db, "user1").await; // AuthUser is ID 1
+    create_test_user(&app.db, "user2").await;
+
+    // 1. user1 follows user2
+    let response =
+        make_post_request(app.router.clone(), "/users/user2/follow", "".to_string()).await;
+    assert_eq!(response.status(), StatusCode::NO_CONTENT);
+
+    // 2. user1 tries to follow user2 again (should fail)
+    let response =
+        make_post_request(app.router.clone(), "/users/user2/follow", "".to_string()).await;
+    assert_eq!(response.status(), StatusCode::CONFLICT);
+
+    // 3. user1 tries to follow a non-existent user
+    let response =
+        make_post_request(app.router.clone(), "/users/nobody/follow", "".to_string()).await;
+    assert_eq!(response.status(), StatusCode::NOT_FOUND);
+
+    // 4. user1 unfollows user2
+    let response = make_delete_request(app.router.clone(), "/users/user2/follow").await;
+    assert_eq!(response.status(), StatusCode::NO_CONTENT);
+
+    // 5. user1 tries to unfollow user2 again (should fail)
+    let response = make_delete_request(app.router.clone(), "/users/user2/follow").await;
+    assert_eq!(response.status(), StatusCode::NOT_FOUND);
+}

thoughts-backend/tests/api/main.rs

@@ -0,0 +1,29 @@
+use api::setup_router;
+use app::persistence::user::create_user;
+use axum::Router;
+use models::params::user::CreateUserParams;
+use sea_orm::DatabaseConnection;
+use utils::testing::setup_test_db;
+
+pub struct TestApp {
+    pub router: Router,
+    pub db: DatabaseConnection,
+}
+
+pub async fn setup() -> TestApp {
+    let db = setup_test_db("sqlite::memory:")
+        .await
+        .expect("Failed to set up test db");
+    let router = setup_router(db.clone());
+    TestApp { router, db }
+}
+
+// Helper to create users for tests
+pub async fn create_test_user(db: &DatabaseConnection, username: &str) {
+    let params = CreateUserParams {
+        username: username.to_string(),
+    };
+    create_user(db, params)
+        .await
+        .expect("Failed to create test user");
+}

thoughts-backend/tests/api/mod.rs

@@ -1,30 +1,5 @@
-use api::setup_router;
-use utils::testing::setup_test_db;
-
-mod root;
+mod feed;
+mod follow;
+mod main;
+mod thought;
 mod user;
-
-use root::*;
-use user::*;
-
-#[tokio::test]
-async fn root_main() {
-    let db = setup_test_db("sqlite::root?mode=memory&cache=shared")
-        .await
-        .expect("Set up db failed!");
-
-    let app = setup_router(db);
-    test_root(app).await;
-}
-
-#[tokio::test]
-async fn user_main() {
-    let db = setup_test_db("sqlite::user?mode=memory&cache=shared")
-        .await
-        .expect("Set up db failed!");
-
-    let app = setup_router(db);
-    test_post_users(app.clone()).await;
-    test_post_users_error(app.clone()).await;
-    test_get_users(app).await;
-}

thoughts-backend/tests/api/thought.rs

@@ -0,0 +1,36 @@
+use super::main::{create_test_user, setup};
+use axum::http::StatusCode;
+use http_body_util::BodyExt;
+use serde_json::json;
+use utils::testing::{make_delete_request, make_post_request};
+
+#[tokio::test]
+async fn test_thought_endpoints() {
+    let app = setup().await;
+    create_test_user(&app.db, "user1").await; // AuthUser is ID 1
+    create_test_user(&app.db, "user2").await; // Other user is ID 2
+
+    // 1. Post a new thought as user 1
+    let body = json!({ "content": "My first thought!" }).to_string();
+    let response = make_post_request(app.router.clone(), "/thoughts", body).await;
+    assert_eq!(response.status(), StatusCode::CREATED);
+    let body = response.into_body().collect().await.unwrap().to_bytes();
+    let v: serde_json::Value = serde_json::from_slice(&body).unwrap();
+    assert_eq!(v["content"], "My first thought!");
+    assert_eq!(v["author_username"], "user1");
+    let thought_id = v["id"].as_i64().unwrap();
+
+    // 2. Post a thought with invalid content
+    let body = json!({ "content": "" }).to_string(); // Too short
+    let response = make_post_request(app.router.clone(), "/thoughts", body).await;
+    assert_eq!(response.status(), StatusCode::UNPROCESSABLE_ENTITY);
+
+    // 3. Attempt to delete another user's thought (user1 tries to delete a non-existent thought, but let's pretend it's user2's)
+    let response = make_delete_request(app.router.clone(), &format!("/thoughts/999")).await;
+    assert_eq!(response.status(), StatusCode::NOT_FOUND);
+
+    // 4. Delete the thought created in step 1
+    let response =
+        make_delete_request(app.router.clone(), &format!("/thoughts/{}", thought_id)).await;
+    assert_eq!(response.status(), StatusCode::NO_CONTENT);
+}

thoughts-backend/utils/src/testing/api/mod.rs

@@ -19,3 +19,15 @@ pub async fn make_post_request(app: Router, url: &str, body: String) -> Response
     .await
     .unwrap()
 }
+
+pub async fn make_delete_request(app: Router, url: &str) -> Response {
+    app.oneshot(
+        Request::builder()
+            .method("DELETE")
+            .uri(url)
+            .body(Body::empty())
+            .unwrap(),
+    )
+    .await
+    .unwrap()
+}

thoughts-backend/utils/src/testing/mod.rs

@@ -1,5 +1,5 @@
 mod api;
 mod db;
 
-pub use api::{make_get_request, make_post_request};
+pub use api::{make_delete_request, make_get_request, make_post_request};
 pub use db::setup_test_db;

thoughts-frontend/app/page.tsx

@@ -1,103 +1,158 @@
-import Image from "next/image";
+"use client";
+
+import { useState, useEffect, FormEvent } from "react";
+
+interface Thought {
+  id: number;
+  author_id: number;
+  content: string;
+  created_at: string;
+}
 
 export default function Home() {
-  return (
-    <div className="font-sans grid grid-rows-[20px_1fr_20px] items-center justify-items-center min-h-screen p-8 pb-20 gap-16 sm:p-20">
-      <main className="flex flex-col gap-[32px] row-start-2 items-center sm:items-start">
-        <Image
-          className="dark:invert"
-          src="/next.svg"
-          alt="Next.js logo"
-          width={180}
-          height={38}
-          priority
-        />
-        <ol className="font-mono list-inside list-decimal text-sm/6 text-center sm:text-left">
-          <li className="mb-2 tracking-[-.01em]">
-            Get started by editing{" "}
-            <code className="bg-black/[.05] dark:bg-white/[.06] font-mono font-semibold px-1 py-0.5 rounded">
-              app/page.tsx
-            </code>
-            .
-          </li>
-          <li className="tracking-[-.01em]">
-            Save and see your changes instantly.
-          </li>
-        </ol>
+  // State to store the list of thoughts for the feed
+  const [thoughts, setThoughts] = useState<Thought[]>([]);
+  // State for the content of the new thought being typed
+  const [newThoughtContent, setNewThoughtContent] = useState("");
+  // State to manage loading status
+  const [isLoading, setIsLoading] = useState(true);
+  // State to hold any potential errors during API calls
+  const [error, setError] = useState<string | null>(null);
 
-        <div className="flex gap-4 items-center flex-col sm:flex-row">
-          <a
-            className="rounded-full border border-solid border-transparent transition-colors flex items-center justify-center bg-foreground text-background gap-2 hover:bg-[#383838] dark:hover:bg-[#ccc] font-medium text-sm sm:text-base h-10 sm:h-12 px-4 sm:px-5 sm:w-auto"
-            href="https://vercel.com/new?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
+  // Function to fetch the feed from the backend API
+  const fetchFeed = async () => {
+    try {
+      setError(null);
+      const response = await fetch("http://localhost:8000/api/feed");
+      if (!response.ok) {
+        throw new Error(`HTTP error! status: ${response.status}`);
+      }
+      const data = await response.json();
+      // The API returns { thoughts: [...] }, so we access the nested array
+      setThoughts(data.thoughts || []);
+    } catch (e: unknown) {
+      console.error("Failed to fetch feed:", e);
+      setError(
+        "Could not load the feed. The backend might be busy. Please try refreshing."
+      );
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  // useEffect hook to fetch the feed when the component first loads
+  useEffect(() => {
+    fetchFeed();
+  }, []);
+
+  // Handler for submitting the new thought form
+  const handleSubmitThought = async (e: FormEvent) => {
+    e.preventDefault();
+    if (!newThoughtContent.trim()) return; // Prevent empty posts
+
+    try {
+      const response = await fetch("http://localhost:8000/api/thoughts", {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/json",
+        },
+        // We are hardcoding author_id: 1 as we don't have auth yet
+        body: JSON.stringify({ content: newThoughtContent, author_id: 1 }),
+      });
+
+      if (!response.ok) {
+        throw new Error(`HTTP error! status: ${response.status}`);
+      }
+
+      // Clear the input box
+      setNewThoughtContent("");
+      // Refresh the feed to show the new post
+      fetchFeed();
+    } catch (e: unknown) {
+      console.error("Failed to post thought:", e);
+      setError("Failed to post your thought. Please try again.");
+    }
+  };
+
+  return (
+    <div className="font-sans bg-gradient-to-br from-sky-200 via-teal-100 to-green-200 min-h-screen text-gray-800">
+      <div className="container mx-auto max-w-2xl p-4 sm:p-6">
+        {/* Header */}
+        <header className="text-center my-6">
+          <h1
+            className="text-5xl font-bold text-white"
+            style={{ textShadow: "2px 2px 4px rgba(0,0,0,0.2)" }}
           >
-            <Image
-              className="dark:invert"
-              src="/vercel.svg"
-              alt="Vercel logomark"
-              width={20}
-              height={20}
+            Thoughts
+          </h1>
+          <p className="text-white/80 mt-2">
+            Your space on the decentralized web.
+          </p>
+        </header>
+
+        {/* New Thought Form */}
+        <div className="bg-white/70 backdrop-blur-lg rounded-xl shadow-lg p-5 mb-8">
+          <form onSubmit={handleSubmitThought}>
+            <textarea
+              value={newThoughtContent}
+              onChange={(e) => setNewThoughtContent(e.target.value)}
+              className="w-full h-24 p-3 rounded-lg border border-gray-300 focus:ring-2 focus:ring-sky-400 focus:outline-none resize-none transition-shadow"
+              placeholder="What's on your mind?"
+              maxLength={128}
             />
-            Deploy now
-          </a>
-          <a
-            className="rounded-full border border-solid border-black/[.08] dark:border-white/[.145] transition-colors flex items-center justify-center hover:bg-[#f2f2f2] dark:hover:bg-[#1a1a1a] hover:border-transparent font-medium text-sm sm:text-base h-10 sm:h-12 px-4 sm:px-5 w-full sm:w-auto md:w-[158px]"
-            href="https://nextjs.org/docs?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-            target="_blank"
-            rel="noopener noreferrer"
-          >
-            Read our docs
-          </a>
+            <div className="flex justify-between items-center mt-3">
+              <span className="text-sm text-gray-500">
+                {128 - newThoughtContent.length} characters remaining
+              </span>
+              <button
+                type="submit"
+                className="px-6 py-2 bg-sky-500 text-white font-semibold rounded-full shadow-md hover:bg-sky-600 active:scale-95 transition-all duration-150 ease-in-out disabled:bg-gray-400"
+                disabled={!newThoughtContent.trim()}
+              >
+                Post
+              </button>
+            </div>
+          </form>
         </div>
-      </main>
-      <footer className="row-start-3 flex gap-[24px] flex-wrap items-center justify-center">
-        <a
-          className="flex items-center gap-2 hover:underline hover:underline-offset-4"
-          href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <Image
-            aria-hidden
-            src="/file.svg"
-            alt="File icon"
-            width={16}
-            height={16}
-          />
-          Learn
-        </a>
-        <a
-          className="flex items-center gap-2 hover:underline hover:underline-offset-4"
-          href="https://vercel.com/templates?framework=next.js&utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <Image
-            aria-hidden
-            src="/window.svg"
-            alt="Window icon"
-            width={16}
-            height={16}
-          />
-          Examples
-        </a>
-        <a
-          className="flex items-center gap-2 hover:underline hover:underline-offset-4"
-          href="https://nextjs.org?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-          target="_blank"
-          rel="noopener noreferrer"
-        >
-          <Image
-            aria-hidden
-            src="/globe.svg"
-            alt="Globe icon"
-            width={16}
-            height={16}
-          />
-          Go to nextjs.org →
-        </a>
-      </footer>
+
+        {/* Feed Section */}
+        <main>
+          {isLoading ? (
+            <p className="text-center text-gray-600">Loading feed...</p>
+          ) : error ? (
+            <div className="bg-red-100 border border-red-400 text-red-700 px-4 py-3 rounded-lg text-center">
+              <p>{error}</p>
+            </div>
+          ) : thoughts.length === 0 ? (
+            <p className="text-center text-gray-600">
+              The feed is empty. Follow some users to see their thoughts!
+            </p>
+          ) : (
+            <div className="space-y-4">
+              {thoughts.map((thought) => (
+                <div
+                  key={thought.id}
+                  className="bg-white/80 backdrop-blur-lg rounded-xl shadow-lg p-4 transition-transform hover:scale-[1.02]"
+                >
+                  <div className="flex items-center mb-2">
+                    <div className="w-10 h-10 rounded-full bg-gradient-to-br from-green-300 to-sky-400 flex items-center justify-center font-bold text-white mr-3">
+                      {/* Placeholder for avatar */}
+                      {thought.author_id}
+                    </div>
+                    <div>
+                      <p className="font-bold">User {thought.author_id}</p>
+                      <p className="text-xs text-gray-500">
+                        {new Date(thought.created_at).toLocaleString()}
+                      </p>
+                    </div>
+                  </div>
+                  <p className="text-gray-800 break-words">{thought.content}</p>
+                </div>
+              ))}
+            </div>
+          )}
+        </main>
+      </div>
     </div>
   );
 }