azure: identify platform by well known value in chassis asset tag.

Azure sets a known chassis asset tag to 7783-7084-3265-9085-8269-3286-77.
We can inspect this in both ds-identify and DataSource.get_data to
determine whether we are on Azure.

Added unit tests to cover these changes
and some minor tweaks to Exception error message content to give more
context on malformed or missing ovf-env.xml files.

LP: #1693939

1 files changed, 24 insertions, 11 deletions

diff --git a/tools/ds-identify b/tools/ds-identify
index 5fc500b9..546e0f59 100755
--- a/tools/ds-identify
+++ b/tools/ds-identify
@@ -85,6 +85,7 @@ DI_MAIN=${DI_MAIN:-main}
 
 DI_DEFAULT_POLICY="search,found=all,maybe=all,notfound=${DI_DISABLED}"
 DI_DEFAULT_POLICY_NO_DMI="search,found=all,maybe=all,notfound=${DI_ENABLED}"
+DI_DMI_CHASSIS_ASSET_TAG=""
 DI_DMI_PRODUCT_NAME=""
 DI_DMI_SYS_VENDOR=""
 DI_DMI_PRODUCT_SERIAL=""
@@ -259,6 +260,12 @@ read_kernel_cmdline() {
     DI_KERNEL_CMDLINE="$cmdline"
 }
 
+read_dmi_chassis_asset_tag() {
+    cached "${DI_DMI_CHASSIS_ASSET_TAG}" && return
+    get_dmi_field chassis_asset_tag
+    DI_DMI_CHASSIS_ASSET_TAG="$_RET"
+}
+
 read_dmi_sys_vendor() {
     cached "${DI_DMI_SYS_VENDOR}" && return
     get_dmi_field sys_vendor
@@ -386,6 +393,14 @@ read_pid1_product_name() {
     DI_PID_1_PRODUCT_NAME="$product_name"
 }
 
+dmi_chassis_asset_tag_matches() {
+    is_container && return 1
+    case "${DI_DMI_CHASSIS_ASSET_TAG}" in
+        $1) return 0;;
+    esac
+    return 1
+}
+
 dmi_product_name_matches() {
     is_container && return 1
     case "${DI_DMI_PRODUCT_NAME}" in
@@ -402,11 +417,6 @@ dmi_product_serial_matches() {
     return 1
 }
 
-dmi_product_name_is() {
-    is_container && return 1
-    [ "${DI_DMI_PRODUCT_NAME}" = "$1" ]
-}
-
 dmi_sys_vendor_is() {
     is_container && return 1
     [ "${DI_DMI_SYS_VENDOR}" = "$1" ]
@@ -478,7 +488,7 @@ dscheck_CloudStack() {
 
 dscheck_CloudSigma() {
     # http://paste.ubuntu.com/23624795/
-    dmi_product_name_is "CloudSigma" && return $DS_FOUND
+    dmi_product_name_matches "CloudSigma" && return $DS_FOUND
     return $DS_NOT_FOUND
 }
 
@@ -654,6 +664,8 @@ dscheck_Azure() {
     #  UUID="112D211272645f72" LABEL="rd_rdfe_stable.161212-1209"
     #  TYPE="udf">/dev/sr0</device>
     #
+    local azure_chassis="7783-7084-3265-9085-8269-3286-77"
+    dmi_chassis_asset_tag_matches "${azure_chassis}" && return $DS_FOUND
     check_seed_dir azure ovf-env.xml && return ${DS_FOUND}
 
     [ "${DI_VIRT}" = "microsoft" ] || return ${DS_NOT_FOUND}
@@ -786,7 +798,7 @@ dscheck_Ec2() {
 }
 
 dscheck_GCE() {
-    if dmi_product_name_is "Google Compute Engine"; then
+    if dmi_product_name_matches "Google Compute Engine"; then
         return ${DS_FOUND}
     fi
     # product name is not guaranteed (LP: #1674861)
@@ -807,10 +819,10 @@ dscheck_OpenStack() {
         return ${DS_NOT_FOUND}
     fi
     local nova="OpenStack Nova" compute="OpenStack Compute"
-    if dmi_product_name_is "$nova"; then
+    if dmi_product_name_matches "$nova"; then
         return ${DS_FOUND}
     fi
-    if dmi_product_name_is "$compute"; then
+    if dmi_product_name_matches "$compute"; then
         # RDO installed nova (LP: #1675349).
         return ${DS_FOUND}
     fi
@@ -823,7 +835,7 @@ dscheck_OpenStack() {
 
 dscheck_AliYun() {
     check_seed_dir "AliYun" meta-data user-data && return ${DS_FOUND}
-    if dmi_product_name_is "Alibaba Cloud ECS"; then
+    if dmi_product_name_matches "Alibaba Cloud ECS"; then
         return $DS_FOUND
     fi
     return $DS_NOT_FOUND
@@ -889,6 +901,7 @@ collect_info() {
     read_config
     read_datasource_list
     read_dmi_sys_vendor
+    read_dmi_chassis_asset_tag
     read_dmi_product_name
     read_dmi_product_serial
     read_dmi_product_uuid
@@ -903,7 +916,7 @@ print_info() {
 _print_info() {
     local n="" v="" vars=""
     vars="DMI_PRODUCT_NAME DMI_SYS_VENDOR DMI_PRODUCT_SERIAL"
-    vars="$vars DMI_PRODUCT_UUID PID_1_PRODUCT_NAME"
+    vars="$vars DMI_PRODUCT_UUID PID_1_PRODUCT_NAME DMI_CHASSIS_ASSET_TAG"
     vars="$vars FS_LABELS KERNEL_CMDLINE VIRT"
     vars="$vars UNAME_KERNEL_NAME UNAME_KERNEL_RELEASE UNAME_KERNEL_VERSION"
     vars="$vars UNAME_MACHINE UNAME_NODENAME UNAME_OPERATING_SYSTEM"