Added Now-DNS issue#368

[CyberAustin]

Fixes #368

[CyberAustin]

Crap. Line 137 I left a "debugging statement" in there 😄

[qdm12]

Nice work, thanks 💯 !

Just a few minor changes to be made, thanks 😉

[qdm12]

Also please add nowdns to the list in the readme.md, and add a document docs/nowdns.md

[CyberAustin]

Also please add nowdns to the list in the readme.md, and add a document docs/nowdns.md

Apparently in my sleep deprived state I neglected to add this to my last commit 😬

[CyberAustin]

Changes made. Docker build still failing though.

Step 37/50 : RUN GOARCH="$(xcputranslate translate -targetplatform ${TARGETPLATFORM} -field arch)"     GOARM="$(xcputranslate translate -targetplatform ${TARGETPLATFORM} -field arm)"     go build -trimpath -ldflags="-s -w     -X 'main.version=$VERSION'     -X 'main.created=$CREATED'     -X 'main.commit=$COMMIT'     " -o app cmd/updater/main.go
 ---> Running in 5c6c1893196b
go: invalid GOARM: must be 5, 6, 7
The command '/bin/sh -c GOARCH="$(xcputranslate translate -targetplatform ${TARGETPLATFORM} -field arch)"     GOARM="$(xcputranslate translate -targetplatform ${TARGETPLATFORM} -field arm)"     go build -trimpath -ldflags="-s -w     -X 'main.version=$VERSION'     -X 'main.created=$CREATED'     -X 'main.commit=$COMMIT'     " -o app cmd/updater/main.go' returned a non-zero code: 2

[qdm12]

The build fails because of go: invalid GOARM: must be 5, 6, 7 it might be a bug from xcputranslate. What's your host platform? You can do uname -a

[CyberAustin]

Linux mint 5.15.0-76-generic #83-Ubuntu SMP Thu Jun 15 19:16:32 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

How would I override it? --build-arg GOARM=5 doesn't seem to help.

edit: Well, if I delete the GOARCH and GOARM lines, it builds just fine. 😂

[CyberAustin]

Fixed the Dockerfile. The ARG TARGETPLATFORM was blank. Everything builds fine now.

Edit: But referencing the Dockerfile from other repos, apparently it is supposed to build just fine with TARGETPLATFORM being blank. So IDK.

[CyberAustin]

Okay, builds inside of a GitHub codespace container just fine with the original Dockerfile. Build output below.

#1 transferring dockerfile: 32B done
#1 DONE 0.1s

#2 [internal] load .dockerignore
#2 transferring context: 35B done
#2 DONE 0.2s

#3 [internal] load metadata for docker.io/library/golang:1.20-alpine3.18
#3 DONE 0.5s

#4 [internal] load metadata for docker.io/qmcgaw/xcputranslate:v0.6.0
#4 DONE 0.5s

#5 [internal] load metadata for docker.io/qmcgaw/binpot:mockgen-v1.6.0
#5 DONE 0.5s

#6 [internal] load metadata for docker.io/qmcgaw/binpot:golangci-lint-v1.53.2
#6 DONE 0.6s

#7 [mockgen 1/1] FROM docker.io/qmcgaw/binpot:mockgen-v1.6.0@sha256:9338f2b706b42197fc5d46f02f03f8a93029b7bea9c819068cb2581f75d3d5b6
#7 DONE 0.0s

#8 [golangci-lint 1/1] FROM docker.io/qmcgaw/binpot:golangci-lint-v1.53.2@sha256:f2517d64e10011cbb98d9ae57f3ddd26d82237f139084767a001df162e1252a6
#8 DONE 0.0s

#9 [xcputranslate 1/1] FROM docker.io/qmcgaw/xcputranslate:v0.6.0@sha256:610582458e71facb54fd16cfb207e8b233afb6e15178742aa5332fd257926b74
#9 DONE 0.0s

#10 [base  1/11] FROM docker.io/library/golang:1.20-alpine3.18@sha256:7839c9f01b5502d7cb5198b2c032857023424470b3e31ae46a8261ffca72912a
#10 DONE 0.0s

#11 [internal] load build context
#11 transferring context: 18.88kB 0.0s done
#11 DONE 0.1s

#12 [base  9/11] COPY pkg/ ./pkg/
#12 CACHED

#13 [build 1/1] RUN GOARCH="$(xcputranslate translate -targetplatform linux/amd64 -field arch)"     GOARM="$(xcputranslate translate -targetplatform linux/amd64 -field arm)"     go build -trimpath -ldflags="-s -w     -X 'main.version=unknown'     -X 'main.created=an unknown date'     -X 'main.commit=unknown'     " -o app cmd/updater/main.go
#13 CACHED

#14 [base  4/11] COPY --from=xcputranslate /xcputranslate /usr/local/bin/xcputranslate
#14 CACHED

#15 [base  5/11] COPY --from=golangci-lint /bin /go/bin/golangci-lint
#15 CACHED

#16 [base  3/11] RUN apk --update add git g++ findutils
#16 CACHED

#17 [base  2/11] WORKDIR /tmp/gobuild
#17 CACHED

#18 [base  8/11] RUN go mod download
#18 CACHED

#19 [base 10/11] COPY cmd/ ./cmd/
#19 CACHED

#20 [base 11/11] COPY internal/ ./internal/
#20 CACHED

#21 [base  6/11] COPY --from=mockgen /bin /go/bin/mockgen
#21 CACHED

#22 [base  7/11] COPY go.mod go.sum ./
#22 CACHED

#23 [stage-8 1/1] COPY --from=build --chown=1000:1000 /tmp/gobuild/app /updater/app
#23 CACHED

#24 exporting to image
#24 exporting layers done
#24 writing image sha256:bececb724395b216a77f82f08132c1b7a9c0c75bdb63bf3073f328d9a8fc8661 0.0s done
#24 naming to docker.io/library/ddns-updater-blank done
#24 DONE 0.0s
WARNING: buildx: failed to read current commit information with git rev-parse --is-inside-work-tree

[qdm12]

That's most likely because your local docker is a bit outdated or doesn't use buildkit/buildx, which should set TARGETPLATFORM to linux/amd64 in your case automatically.

Now I'm trying to figure out how to prevent this issue arising again on such Docker setups.

First, there is a bug where TARGETPLATFORM cannot have a default in the Dockerfile: docker/buildx#510 so setting it to linux/amd64 won't work for cross compilation.

As it is, xcputranslate fails and exits with 1, for example xcputranslate translate -targetplatform "" -field arch produces

Fatal error: invalid platform: string is malformed: ""
exit status 1

But because it's wrapped in a subshell in GOARCH="$(xcputranslate translate -targetplatform ${TARGETPLATFORM} -field arch)", the command is only silently failing and really GOARM is set to Fatal error: invalid platform: string is malformed: ""... Maybe you would have an idea how to fix the GOARCH and GOARM lines in the Dockerfile so it crashes if xcputranslate exits with 1??

There is also an alternative where xcputranslate handles the empty TARGETPLATFORM string and outputs the current platform, but that's a bit of a pain to implement and reliably detect the platform version, so I would rather avoid.

[qdm12]

I did that and it was failing to update the record.
It has to be passed as "@", otherwise the API throws a "nohost" error.
Fair point. Fixed.

If the host can only be @ (not * or abc), then remove the option host from the config and the field host in the provider struct.

[CyberAustin]

But without host field, it fails. "nohost" is what the API returns. edit: I see the issue. Without the `host` field set to `@`, a period gets added to the front of the fqdn somewhere, causing the error.

[CyberAustin]

I did that and it was failing to update the record.
It has to be passed as "@", otherwise the API throws a "nohost" error.
Fair point. Fixed.

If the host can only be @ (not * or abc), then remove the option host from the config and the field host in the provider struct.

This opens up a whole lot of other issues, like having to refactor host out of the rest of the file, redefine or replace utils.ToString(p.domain, p.host, constants.NowDNS, p.ipVersion) as a variadatic function. I think I found a simpler solution that will be in the next commit that I think will work just as well.

[CyberAustin]

Basically just set host to @ in the provider.go file so that it is always that way, and removed any reference to host in the documentation.

[CyberAustin]

I think the solution is good, simple and ready to merge into master.

[qdm12]

Awesome, great work 💯 Merging it 😉

side note: I went ahead and removed the host injection and host field in the struct (hardcoding @ where needed), since that was itching my brain too much to have a constant struct field and unused argument injected.