[bugfix] #621: add weak type handing to mapstructure decode (#625)

* Drone sig (#623)

* accept weakly typed input on mapstructure decode i.e. .UnmarshalMap()

Signed-off-by: kim <grufwub@gmail.com>

* add envparsing script to test for panics during environment variable parsing

Signed-off-by: kim <grufwub@gmail.com>

* add envparsing.sh script to drone commands

Signed-off-by: kim <grufwub@gmail.com>

* update drone signature

Co-authored-by: kim <grufwub@gmail.com>

* compare expected with output

* update expected output of envparsing

* update expected output to correct value

* use viper's unmarshal function instead
There were problems with marshalling
string slices from viper into the st.config
struct with the other function. Now, we
can use viper's unmarshal function and pass
in the custom decoder config that we need
as a hook. This ensures that we marshal
string slices from viper into our config
struct correctly.

Co-authored-by: tobi <31960611+tsmethurst@users.noreply.github.com>
Co-authored-by: tsmethurst <tobi.smethurst@protonmail.com>

4 files changed, 77 insertions, 12 deletions

diff --git a/.drone.yml b/.drone.yml
index a96d54649..bec186175 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -38,6 +38,7 @@ steps:
       - apk update --no-cache && apk add git
       - CGO_ENABLED=0 GTS_DB_TYPE="sqlite" GTS_DB_ADDRESS=":memory:" go test ./...
       - CGO_ENABLED=0 ./test/cliparsing.sh
+      - CGO_ENABLED=0 ./test/envparsing.sh
     when:
       event:
         include:
@@ -145,6 +146,6 @@ steps:
 
 ---
 kind: signature
-hmac: f3cf4e422d9ce7dc0a881da429db628232e2f9e91383ee5a33cf4f13542c0a23
+hmac: adfcc11559717e4e371e714f3ac19ab528208f678961436f316f491bf82de8ad
 
 ...
diff --git a/internal/config/config.go b/internal/config/config.go
index 573f2b3a2..3a1775778 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -130,12 +130,3 @@ func (cfg *Configuration) MarshalMap() (map[string]interface{}, error) {
 	}
 	return dst, nil
 }
-
-// UnmarshalMap will unmarshal a map structure into the receiving Configuration.
-func (cfg *Configuration) UnmarshalMap(src map[string]interface{}) error {
-	dec, _ := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
-		TagName: "name",
-		Result:  cfg,
-	})
-	return dec.Decode(src)
-}
diff --git a/internal/config/state.go b/internal/config/state.go
index 70972a835..1364fb84e 100644
--- a/internal/config/state.go
+++ b/internal/config/state.go
@@ -22,6 +22,7 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/mitchellh/mapstructure"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
@@ -129,8 +130,10 @@ func (st *ConfigState) reloadToViper() {
 
 // reloadFromViper will reload Configuration{} values from viper.
 func (st *ConfigState) reloadFromViper() {
-	err := st.config.UnmarshalMap(st.viper.AllSettings())
-	if err != nil {
+	if err := st.viper.Unmarshal(&st.config, func(c *mapstructure.DecoderConfig) {
+		c.TagName = "name"
+		c.ZeroFields = true // empty the config struct before we marshal values into it
+	}); err != nil {
 		panic(err)
 	}
 }
diff --git a/test/envparsing.sh b/test/envparsing.sh
new file mode 100755
index 000000000..8bced72e9
--- /dev/null
+++ b/test/envparsing.sh
@@ -0,0 +1,70 @@
+#!/bin/sh
+
+set -eu
+
+EXPECTED='{"account-domain":"peepee","accounts-approval-required":false,"accounts-reason-required":false,"accounts-registration-open":true,"advanced-cookies-samesite":"strict","application-name":"gts","bind-address":"127.0.0.1","config-path":"./test/test.yaml","db-address":":memory:","db-database":"gotosocial_prod","db-password":"hunter2","db-port":6969,"db-tls-ca-cert":"","db-tls-mode":"disable","db-type":"sqlite","db-user":"sex-haver","email":"","host":"example.com","letsencrypt-cert-dir":"/gotosocial/storage/certs","letsencrypt-email-address":"","letsencrypt-enabled":true,"letsencrypt-port":80,"log-db-queries":true,"log-level":"info","media-description-max-chars":5000,"media-description-min-chars":69,"media-image-max-size":420,"media-remote-cache-days":30,"media-video-max-size":420,"oidc-client-id":"1234","oidc-client-secret":"shhhh its a secret","oidc-enabled":true,"oidc-idp-name":"sex-haver","oidc-issuer":"whoknows","oidc-scopes":["read","write"],"oidc-skip-verification":true,"password":"","path":"","port":6969,"protocol":"http","smtp-from":"queen@terfisland.org","smtp-host":"example.com","smtp-password":"hunter2","smtp-port":4269,"smtp-username":"sex-haver","software-version":"","statuses-cw-max-chars":420,"statuses-max-chars":69,"statuses-media-max-files":1,"statuses-poll-max-options":1,"statuses-poll-option-max-chars":50,"storage-backend":"local","storage-local-base-path":"/root/store","syslog-address":"127.0.0.1:6969","syslog-enabled":true,"syslog-protocol":"udp","trusted-proxies":["127.0.0.1/32","0.0.0.0/0"],"username":"","web-asset-base-dir":"/root","web-template-base-dir":"/root"}'
+
+# Set all the environment variables to 
+# ensure that these are parsed without panic
+OUTPUT=$(GTS_LOG_LEVEL='info' \
+GTS_LOG_DB_QUERIES=true \
+GTS_APPLICATION_NAME=gts \
+GTS_HOST=example.com \
+GTS_ACCOUNT_DOMAIN='peepee' \
+GTS_PROTOCOL=http \
+GTS_BIND_ADDRESS='127.0.0.1' \
+GTS_PORT=6969 \
+GTS_TRUSTED_PROXIES='' \
+GTS_DB_TYPE='sqlite' \
+GTS_DB_ADDRESS=':memory:' \
+GTS_DB_PORT=6969 \
+GTS_DB_USER='sex-haver' \
+GTS_DB_PASSWORD='hunter2' \
+GTS_DB_DATABASE='gotosocial_prod' \
+GTS_TLS_MODE='' \
+GTS_DB_TLS_CA_CERT='' \
+GTS_WEB_TEMPLATE_BASE_DIR='/root' \
+GTS_WEB_ASSET_BASE_DIR='/root' \
+GTS_ACCOUNTS_REGISTRATION_OPEN=true \
+GTS_ACCOUNTS_APPROVAL_REQUIRED=false \
+GTS_ACCOUNTS_REASON_REQUIRED=false \
+GTS_MEDIA_IMAGE_MAX_SIZE=420 \
+GTS_MEDIA_VIDEO_MAX_SIZE=420 \
+GTS_MEDIA_DESCRIPTION_MIN_CHARS=69 \
+GTS_MEDIA_DESCRIPTION_MAX_CHARS=5000 \
+GTS_MEDIA_REMOTE_CACHE_DAYS=30 \
+GTS_STORAGE_BACKEND='local' \
+GTS_STORAGE_LOCAL_BASE_PATH='/root/store' \
+GTS_STATUSES_MAX_CHARS=69 \
+GTS_STATUSES_CW_MAX_CHARS=420 \
+GTS_STATUSES_POLL_MAX_OPTIONS=1 \
+GTS_STATUSES_POLL_OPTIONS_MAX_CHARS=69 \
+GTS_STATUSES_MEDIA_MAX_FILES=1 \
+GTS_LETS_ENCRYPT_ENABLED=false \
+GTS_LETS_ENCRYPT_PORT=8080 \
+GTS_LETS_ENCRYPT_CERT_DIR='/root/certs' \
+GTS_LETS_ENCRYPT_EMAIL_ADDRESS='le@example.com' \
+GTS_OIDC_ENABLED=true \
+GTS_OIDC_IDP_NAME='sex-haver' \
+GTS_OIDC_SKIP_VERIFICATION=true \
+GTS_OIDC_ISSUER='whoknows' \
+GTS_OIDC_CLIENT_ID='1234' \
+GTS_OIDC_CLIENT_SECRET='shhhh its a secret' \
+GTS_OIDC_SCOPES='read,write' \
+GTS_SMTP_HOST='example.com' \
+GTS_SMTP_PORT=4269 \
+GTS_SMTP_USERNAME='sex-haver' \
+GTS_SMTP_PASSWORD='hunter2' \
+GTS_SMTP_FROM='queen@terfisland.org' \
+GTS_SYSLOG_ENABLED=true \
+GTS_SYSLOG_PROTOCOL='udp' \
+GTS_SYSLOG_ADDRESS='127.0.0.1:6969' \
+GTS_ADVANCED_COOKIES_SAMESITE='strict' \
+go run ./cmd/gotosocial/... --config-path $(dirname ${0})/test.yaml debug config)
+
+if [ "${OUTPUT}" != "${EXPECTED}" ]; then
+    echo "OUTPUT not equal EXPECTED"
+    exit 1
+else
+    echo "OK"
+fi