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open Piaf
type pool = ((module Rapper_helper.CONNECTION), Caqti_error.t) Caqti_eio.Pool.t
(* This is the main handler function for the GET /posts endpoint. *)
(* It takes a database connection pool and a Piaf request as input. *)
let get_posts (db_pool : pool) (_request : Request.t) =
(* Use a connection from the pool. Caqti_eio.Pool.use handles acquiring and releasing the connection. *)
Caqti_eio.Pool.use
(fun conn ->
(* Call the get_poasts function from the Query module to fetch posts from the database. *)
let posts_or_error = Query.get_poasts () conn in
(* Pattern match on the result of the database query. *)
match posts_or_error with
(* If the query is successful, the result is a list of posts. *)
| Ok posts ->
(* Map the list of post tuples to a Yojson list. *)
let json =
`List
((* For each post tuple, create a JSON object. *)
List.map
(fun (post : Query.post_summary) -> `Assoc [ "title", `String post.title ])
posts)
in
(* Return a 200 OK response with the JSON body. *)
Ok (Response.of_string ~body:(Yojson.Safe.to_string json) `OK)
(* If the query fails, log the error and return a 500 Internal Server Error response. *)
| Error err ->
Logs.err (fun m -> m "Database error: %a" Caqti_error.pp err);
Ok (Response.create `Internal_server_error))
db_pool
;;
(* Handler for GET /posts/:id - gets a single post by ID *)
let get_post post_id (db_pool : pool) (_request : Request.t) =
Caqti_eio.Pool.use
(fun conn ->
let post_or_error = Query.get_poast post_id conn in
match post_or_error with
| Ok (Some post) ->
let json =
`Assoc
[ "id", `Int post.id
; "title", `String post.title
; "content", `String post.content
; "date", `String post.date
; "tags", `String post.tags
; "url", `String post.url
]
in
Ok (Response.of_string ~body:(Yojson.Safe.to_string json) `OK)
| Ok None -> Ok (Response.create `Not_found)
| Error err ->
Logs.err (fun m -> m "Database error: %a" Caqti_error.pp err);
Ok (Response.create `Internal_server_error))
db_pool
;;
(* Handler for GET /comments/:id - gets a single comment by ID *)
let get_comment comment_id (db_pool : pool) (_request : Request.t) =
Caqti_eio.Pool.use
(fun conn ->
let comment_or_error = Query.Query.comment ~id:comment_id conn in
match comment_or_error with
| Ok (Some comment) ->
let json =
`Assoc
[ "id", `Int comment.id
; "content", `String comment.content
; "date", `String comment.date
; "tags", `String comment.tags
; "url", `String comment.url
]
in
Ok (Response.of_string ~body:(Yojson.Safe.to_string json) `OK)
| Ok None -> Ok (Response.create `Not_found)
| Error err ->
Logs.err (fun m -> m "Database error: %a" Caqti_error.pp err);
Ok (Response.create `Internal_server_error))
db_pool
;;
(* Handler for GET /users/:username/comments - gets comments by a user *)
let get_user_comments username (db_pool : pool) (_request : Request.t) =
Caqti_eio.Pool.use
(fun conn ->
let comments_or_error = Query.Query.user_comments ~username conn in
match comments_or_error with
| Ok comments ->
let json =
`List
(List.map
(fun (comment : Query.comment) ->
`Assoc
[ "id", `Int comment.id
; "content", `String comment.content
; "date", `String comment.date
; "tags", `String comment.tags
; "url", `String comment.url
])
comments)
in
Ok (Response.of_string ~body:(Yojson.Safe.to_string json) `OK)
| Error err ->
Logs.err (fun m -> m "Database error: %a" Caqti_error.pp err);
Ok (Response.create `Internal_server_error))
db_pool
;;
(* Handler for GET /posts/:id/comments - gets comments for a post *)
let get_post_comments post_id (db_pool : pool) (_request : Request.t) =
Caqti_eio.Pool.use
(fun conn ->
let comments_or_error = Query.Query.post_comments ~post_id conn in
match comments_or_error with
| Ok comments ->
let json =
`List
(List.map
(fun (comment : Query.comment) ->
`Assoc
[ "id", `Int comment.id
; "content", `String comment.content
; "date", `String comment.date
; "tags", `String comment.tags
; "url", `String comment.url
])
comments)
in
Ok (Response.of_string ~body:(Yojson.Safe.to_string json) `OK)
| Error err ->
Logs.err (fun m -> m "Database error: %a" Caqti_error.pp err);
Ok (Response.create `Internal_server_error))
db_pool
;;
(* Handler for GET /comments/:id/children - gets child comments *)
let get_comment_children parent_id (db_pool : pool) (_request : Request.t) =
Caqti_eio.Pool.use
(fun conn ->
let comments_or_error = Query.Query.comment_children ~post_id:parent_id conn in
match comments_or_error with
| Ok comments ->
let json =
`List
(List.map
(fun (comment : Query.comment) ->
`Assoc
[ "id", `Int comment.id
; "content", `String comment.content
; "date", `String comment.date
; "tags", `String comment.tags
; "url", `String comment.url
])
comments)
in
Ok (Response.of_string ~body:(Yojson.Safe.to_string json) `OK)
| Error err ->
Logs.err (fun m -> m "Database error: %a" Caqti_error.pp err);
Ok (Response.create `Internal_server_error))
db_pool
;;
|
