Added HTTP authentication (#44)

Author: rajkumardongre

example/basic_auth.f90

@@ -0,0 +1,19 @@
+program basic_auth
+    ! Making request with HTTP Basic Auth
+    use http, only: response_type, request, pair_type
+    implicit none
+    type(response_type) :: response
+    type(pair_type) :: auth
+
+    ! setting username and password
+    auth = pair_type('user', 'passwd')
+
+    response = request(url='https://httpbin.org/basic-auth/user/passwd', auth=auth)
+    if(.not. response%ok) then
+        print *,'Error message : ', response%err_msg
+    else
+        print *, 'Response Code    : ', response%status_code
+        print *, 'Response Content : ', response%content
+    end if
+
+end program basic_auth

example/post_form_data.f90

@@ -4,7 +4,6 @@ program post_form_data
     use http, only: response_type, request, HTTP_POST, pair_type
     implicit none
     type(response_type) :: response
-    type(pair_type), allocatable :: req_header(:)
     type(pair_type), allocatable :: form_data(:)
 
     ! Storing form data in a array of pair_type object, each pair_type object 

src/http/http_client.f90

@@ -19,7 +19,8 @@ module http_client
         CURLOPT_WRITEDATA, CURLOPT_WRITEFUNCTION, &
         CURLOPT_POSTFIELDS, CURLOPT_POSTFIELDSIZE_LARGE, curl_easy_escape, &
         curl_mime_init, curl_mime_addpart, curl_mime_filedata,curl_mime_name, &
-        CURLOPT_MIMEPOST,curl_mime_data, CURL_ZERO_TERMINATED
+        CURLOPT_MIMEPOST,curl_mime_data, CURL_ZERO_TERMINATED, &
+        CURLOPT_HTTPAUTH, CURLAUTH_BASIC, CURLOPT_USERNAME, CURLOPT_PASSWORD
     use stdlib_optval, only: optval
     use http_request, only: request_type
     use http_response, only: response_type
@@ -53,7 +54,7 @@ module http_client
     ! new client_type object using the request object as a parameter and sends the request to the server
     ! using the client_get_response method. The function returns the response_type object containing the
     ! server's response.
-    function new_request(url, method, header, data, form, file) result(response)
+    function new_request(url, method, header, data, form, file, auth) result(response)
         !! This function creates a new HTTP request object of the request_type type and sends 
         !! the request to the server using the client_type object. The function takes the URL, 
         !! HTTP method, request headers, request data, and form data as input arguments and returns 
@@ -71,6 +72,8 @@ function new_request(url, method, header, data, form, file) result(response)
             !! An optional array of pair_type objects that specifies the form data to send in the request body.
         type(pair_type), intent(in), optional :: file
             !! An optional pair_type object that specifies the file data to send in the request body.
+        type(pair_type), intent(in), optional :: auth
+            !! An optional pair_type object that stores the username and password for Authentication
         type(response_type) :: response
             !! A response_type object containing the server's response.
         type(request_type) :: request
@@ -109,6 +112,11 @@ function new_request(url, method, header, data, form, file) result(response)
             request%file = file
         end if
 
+        ! setting username and password for Authentication
+        if(present(auth)) then
+            request%auth = auth
+        end if
+
         ! Populates the response 
         client = client_type(request=request)
         response = client%client_get_response()
@@ -163,6 +171,9 @@ & function failed. This can occur due to insufficient memory available in the sy
         ! setting request body
         rc = set_body(curl_ptr, this%request)
 
+        ! setting request authentication
+        rc = set_auth(curl_ptr, this%request)
+
         ! prepare headers for curl
         call prepare_request_header_ptr(header_list_ptr, this%request%header)
 
@@ -315,7 +326,6 @@ function set_body(curl_ptr, request) result(status)
             !! An integer value representing the status of the curl_easy_setopt function call.
 
         integer :: i
-        character(len=:), allocatable :: form_encoded_str
         type(c_ptr) :: mime_ptr, part_ptr
 
         ! if only data is passed
@@ -374,6 +384,26 @@ function set_postfields(curl_ptr, data) result(status)
 
     end function set_postfields
 
+    function set_auth(curl_ptr, request) result(status)
+        !! Set the user name and password for Authentication. It sends the user name 
+        !! and password over the network in plain text, easily captured by others.
+        type(c_ptr), intent(out) :: curl_ptr
+            !! An out argument of type c_ptr that is set to point to a new curl handle.
+        type(request_type), intent(inout) :: request
+            !! The HTTP request
+        integer :: status
+            !! An integer value representing the status of the curl_easy_setopt function call.
+
+        if(allocated(request%auth)) then
+            status = curl_easy_setopt(curl_ptr, CURLOPT_HTTPAUTH, CURLAUTH_BASIC)
+            status = curl_easy_setopt(curl_ptr, CURLOPT_USERNAME, request%auth%name)
+            status = curl_easy_setopt(curl_ptr, CURLOPT_PASSWORD, request%auth%value)
+        else 
+            ! No curl function was called so set status to zero.
+            status = 0
+        end if
+    end function set_auth
+
     ! This function is a callback function used by the libcurl library to handle HTTP responses. It is 
     ! called for each chunk of data received from the server and appends the data to a response_type object. 
     ! The function takes four input arguments: ptr, size, nmemb, and client_data. ptr is a pointer to the 

src/http/http_request.f90

@@ -38,5 +38,7 @@ module http_request
             !! An array of fields in an HTTP form.
         type(pair_type), allocatable :: file
             !! Used to store information about files to be sent in HTTP requests.
+        type(pair_type), allocatable :: auth
+            !! Stores the username and password for Authentication
     end type request_type
 end module http_request

test/test_auth.f90

@@ -0,0 +1,45 @@
+program test_auth
+    use iso_fortran_env, only: stderr => error_unit
+    use http, only : response_type, request, pair_type
+ 
+    implicit none
+    type(response_type) :: res
+    character(:), allocatable :: msg
+    logical :: ok = .true.
+    type(pair_type) :: auth
+
+    ! setting username and password
+    auth = pair_type('user', 'passwd')   
+    res = request(url='https://httpbin.org/basic-auth/user/passwd', auth=auth)
+    
+    msg = 'test_auth: '
+   
+    if (.not. res%ok) then
+        ok = .false.
+        msg = msg // res%err_msg
+        write(stderr, '(a)') msg
+        error stop 1
+    end if
+    
+    ! Status Code Validation
+    if (res%status_code /= 200) then
+        ok = .false.
+        print '(a)', 'Failed : Status Code Validation'
+    end if
+   
+    ! Content Length Validation
+    if (res%content_length /= 47 .or. &
+        len(res%content) /= 47) then
+        ok = .false.
+        print '(a)', 'Failed : Content Length Validation'
+    end if
+
+    if (.not. ok) then 
+        msg = msg // 'Test Case Failed'
+        write(stderr, '(a)'), msg
+        error stop 1
+    else
+        msg = msg // 'All tests passed.'
+        print '(a)', msg 
+    end if
+end program test_auth