imgkit should raise exception if wkhtmltoimage returns with non zero exit code

[ronald]

if libssl1.0-dev is missing and html contains https-style-sheet link it fails silently to load css:

<link href="https://example.com/style.css" rel="stylesheet" />

Expected behavior

ImgKit should raise exception

Current Behavior

ImgKit renders HTML without styles

Possible Solution

Check exit status of wkhtmltoimage.

 sudo apt remove libssl1.0-dev
 bundle exec wkhtmltoimage tmp/code.html tmp/code.jpg

output:

Loading page (1/2)
QSslSocket: cannot resolve CRYPTO_num_locks                  ] 10%
QSslSocket: cannot resolve CRYPTO_set_id_callback
QSslSocket: cannot resolve CRYPTO_set_locking_callback
QSslSocket: cannot resolve sk_free
QSslSocket: cannot resolve sk_num
QSslSocket: cannot resolve sk_pop_free
QSslSocket: cannot resolve sk_value
QSslSocket: cannot resolve SSL_library_init
QSslSocket: cannot resolve SSL_load_error_strings
QSslSocket: cannot resolve SSLv3_client_method
QSslSocket: cannot resolve SSLv23_client_method
QSslSocket: cannot resolve SSLv3_server_method
QSslSocket: cannot resolve SSLv23_server_method
QSslSocket: cannot resolve X509_STORE_CTX_get_chain
QSslSocket: cannot resolve OPENSSL_add_all_algorithms_noconf
QSslSocket: cannot resolve OPENSSL_add_all_algorithms_conf
QSslSocket: cannot resolve SSLeay
QSslSocket: cannot call unresolved function CRYPTO_num_locks
QSslSocket: cannot call unresolved function CRYPTO_set_id_callback
QSslSocket: cannot call unresolved function CRYPTO_set_locking_callback
QSslSocket: cannot call unresolved function SSL_library_init
QSslSocket: cannot call unresolved function SSLv23_client_method
QSslSocket: cannot call unresolved function sk_num
QSslSocket: cannot call unresolved function SSLv23_client_method1%
QSslSocket: cannot call unresolved function SSL_library_init
Rendering (2/2)                                                    
Done                                                               
Exit with code 1 due to network error: UnknownNetworkError
QSslSocket: cannot call unresolved function CRYPTO_num_locks
QSslSocket: cannot call unresolved function CRYPTO_set_id_callback
QSslSocket: cannot call unresolved function CRYPTO_set_locking_callback

check exit code:

 echo $?

output:
1

 sudo apt install libssl1.0-dev
 bundle exec wkhtmltoimage tmp/code.html tmp/code.jpg

output:

Loading page (1/2)
Rendering (2/2)                                                    
Done       

check exit code:

 echo $?

output:
0