Libguestfs - May 2020 - [v2v PATCH] vCenter: require curl in #precheck

The curl binary is used in the VCenter module, so require it up-front.
This let us remove the need to point the user to check whether curl is
installed in an error message.
---
 v2v/input_libvirt_vcenter_https.ml | 13 ++++++++++++-
 v2v/vCenter.ml                     |  2 +-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/v2v/input_libvirt_vcenter_https.ml
b/v2v/input_libvirt_vcenter_https.ml
index ed2e5eed..2265f76e 100644
--- a/v2v/input_libvirt_vcenter_https.ml
+++ b/v2v/input_libvirt_vcenter_https.ml
@@ -19,6 +19,7 @@
 (** [-i libvirt] when the source is VMware vCenter *)
 
 open Common_gettext.Gettext
+open Std_utils
 open Tools_utils
 open Unix_utils.Env
 
@@ -33,13 +34,23 @@ open Printf
 (* Subclass specialized for handling VMware vCenter over https. *)
 class input_libvirt_vcenter_https
         libvirt_conn input_conn input_password parsed_uri server guest +
+  let error_unless_curl_command_exists () +    let curl_binary =
"curl" in
+    try ignore (which curl_binary)
+    with Executable_not_found _ ->
+      error (f_"the ‘%s’ program is not available.  It is needed to
communicate with vCenter.")
+            curl_binary
+  in
+
 object (self)
   inherit input_libvirt libvirt_conn ~input_conn guest
 
   val mutable dcPath = ""
 
   method precheck () -    error_if_libvirt_does_not_support_json_backingfile ()
+    error_if_libvirt_does_not_support_json_backingfile ();
+    error_unless_curl_command_exists ()
 
   method source ?bandwidth ()      debug "input_libvirt_vcenter_https:
source: server %s" server;
diff --git a/v2v/vCenter.ml b/v2v/vCenter.ml
index 586ea3e2..33120e88 100644
--- a/v2v/vCenter.ml
+++ b/v2v/vCenter.ml
@@ -189,7 +189,7 @@ and fetch_headers_from_url password_file uri sslverify
https_url      match statuses with
     | [] ->
        dump_response stderr;
-       error (f_"vcenter: no status code in output of ‘curl’ command.  Is
‘curl’ installed?")
+       error (f_"vcenter: no status code in output of ‘curl’
command.")
     | ss ->
       let s = List.hd (List.rev ss) in
       String.sub s (String.index s ' ' + 1) 3 in
-- 
2.25.4

On Tue, May 26, 2020 at 09:29:24AM +0200, Pino Toscano
wrote:
> The curl binary is used in the VCenter module, so require it up-front.
> This let us remove the need to point the user to check whether curl is
> installed in an error message.
> ---
>  v2v/input_libvirt_vcenter_https.ml | 13 ++++++++++++-
>  v2v/vCenter.ml                     |  2 +-
>  2 files changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/v2v/input_libvirt_vcenter_https.ml
b/v2v/input_libvirt_vcenter_https.ml
> index ed2e5eed..2265f76e 100644
> --- a/v2v/input_libvirt_vcenter_https.ml
> +++ b/v2v/input_libvirt_vcenter_https.ml
> @@ -19,6 +19,7 @@
>  (** [-i libvirt] when the source is VMware vCenter *)
>  
>  open Common_gettext.Gettext
> +open Std_utils
>  open Tools_utils
>  open Unix_utils.Env
>  
> @@ -33,13 +34,23 @@ open Printf
>  (* Subclass specialized for handling VMware vCenter over https. *)
>  class input_libvirt_vcenter_https
>          libvirt_conn input_conn input_password parsed_uri server guest
> +
> +  let error_unless_curl_command_exists () > +    let curl_binary =
"curl" in
> +    try ignore (which curl_binary)
> +    with Executable_not_found _ ->
> +      error (f_"the ‘%s’ program is not available.  It is needed to
communicate with vCenter.")
> +            curl_binary
> +  in
> +
>  object (self)
>    inherit input_libvirt libvirt_conn ~input_conn guest
>  
>    val mutable dcPath = ""
>  
>    method precheck () > -   
error_if_libvirt_does_not_support_json_backingfile ()
> +    error_if_libvirt_does_not_support_json_backingfile ();
> +    error_unless_curl_command_exists ()
>  
>    method source ?bandwidth () >      debug
"input_libvirt_vcenter_https: source: server %s" server;
> diff --git a/v2v/vCenter.ml b/v2v/vCenter.ml
> index 586ea3e2..33120e88 100644
> --- a/v2v/vCenter.ml
> +++ b/v2v/vCenter.ml
> @@ -189,7 +189,7 @@ and fetch_headers_from_url password_file uri sslverify
https_url >      match statuses with
>      | [] ->
>         dump_response stderr;
> -       error (f_"vcenter: no status code in output of ‘curl’ command.
Is ‘curl’ installed?")
> +       error (f_"vcenter: no status code in output of ‘curl’
command.")
>      | ss ->
>        let s = List.hd (List.rev ss) in
>        String.sub s (String.index s ' ' + 1) 3 in

ACK

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into KVM guests.
http://libguestfs.org/virt-v2v